THE BLUE BOOK OF SUBMARINE OPERATIONS

S e a w o l v e s   U n d e r s e a   W a r f a r e   M a n u a l

Revision 20  03/30/2002

 

 

 

Edited by Admiral R.Blue and Vice Admiral Homer

 

Seawolves Virtual Military Command

 

 

Table of Contents

 

I.                   SENSORS

II.                UNDERSTANDING SONAR

III.             SIX MINUTE RULE

IV.              ACTIVE TORPEDO EVASION

V.                 TORPEDO PRESETS

VI.              LINE OF SIGHT (LOS) and TMA

VII.           FLEET OPERATIONS

VIII.        FLEET TRIANGULATION (Homer Plots and Grid)

IX.              COMMUNICATIONS

X.                 PASSIVE TORPEDO EVASION

XI.              TERRAIN AND COVER

XII.           MINE WARFARE

XIII.        SHIP ASPECT AND CONTROL

XIV.         STRATEGIC COMBAT CONSIDERATIONS

XV.            GENERAL COMBAT TACTICS and TECHNIQUES

 

a.       Wild Fish Riding

b.      Tomahawk Sonar Targets

c.       –Deleted-

d.      The Glacier five minute fake out

e.      The Hollywood Charge

f.        Silent Evasion

g.      Hammer Shot

h.      –Deleted-

i.        Finger Fire

j.        The Bulldog Slam

k.      Deep Run Fish

l.        Blue Defense

 

XVI.  MISCELLANEOUS DATA SHEET

I. SENSORS

 

 “If you cause your ship and place the head of a long tube in the water and the other extremity to you ear, you will hear a ship at great distance from you”  – Leonardo da Vinci  (1452-1519)

 

 

On the 688(I), the Sea Wolf, and the Akula class vessels, you have several different sonar and electronic detection systems.  These are mentioned in the manual that comes with the simulation with varying degrees of completeness. Here, each system will be talked about in terms of its combat effectiveness and tactics of employment.

 

PASSIVE SONARS

 

 

SPHERICAL ARRAY

 

  The first of the three passive sonar arrays is called the spherical array or bow sonar.  On the 688(I) and the Sea Wolf, it is the AN/BQQ-5D/E and it has both active (see below) and passive capabilities.  It is sensitive to passive detection ranges from high to mid frequency (750Hz to 2kHz). Environmental conditions will affect its ability to operational detection, but in general for the 688(I) its effective range is about 12,000 yards on average.  For the Sea Wolf, it is closer to 18,000 yards on average.  It is a unidirectional system with a view range of 300 degrees from one side of the ship to the other.  It can be selected on the waterfall display of the sonar room for track analysis (see section on TMA).  Since it is sensitive to higher frequencies it is effective in detecting high frequency sounds better than any other sensor. Since high frequency is associated with small, high speed screws the forward array is your primary torpedo detection mechanism for first contact with an incoming enemy weapon. It shows up as white bearing lines on your auto TMA trace.

 

The Akula uses the MGK-503-M Skat active/passive suite. Its frequency sensitivity some 850Hz to 2.2kHz (approximate). View area is on par with the 688(I) and the Sea Wolf. Detection ranges are approximately 16,000 yards.

HULL ARRAY

 

  The next passive sensor is the wide aperture flank array or hull sonar, the AN/BQG-5D Wide Aperture Array .  This array is used for detecting mid to low frequency (50Hz to 1kHz) sounds and its effective range is about 10,000 yards for the 688(I) and 12,000 yards for the Sea Wolf.  The 688(I) uses the BQR-7 hull array with detection ranges of 7,000 yards. The Akula uses a flank array somewhat similar to the 688(I) design with average ranges of 10,000 yards. The hull array is primarily used in target. It shows up as blue bearing lines on your auto TMA trace. It is your shortest range passive sensor and if you see blue TMA lines, the contact is either very close or very noisy.

 

 

TOWED ARRAY

 

  The last passive sonar system is the towed sonar. The AN/TB-16D thick-line array is used for the 688(I) class and the Sea Wolf. The Sea Wolf class also has the AN/TB-29D thin line array. This is the primary ship sensor and is sensitive to long range low frequency sounds in the 10 to 1.0 kilohertz range.  In good waters (ie quiet), it is good to about 15,000 yards for the 688(I) and 21,000 yards for the Sea Wolf. Convergence zones, layer ducts or skip returns can extend this enormously (TMA tracking at 50,000 yards has been accomplished).  The AN/TB-29D is more sensitive than the AN/TB-16D but suffers more from ship generated noise and ship speed effects. If running slow and quiet the AN/TB-29D is the preferred sensor. If running at a two thirds bell or better, the AN/TB-16D will give better performance. The STARBOARD array on the Sea Wolf is the AN/TB-29D. The PORT array is the AN/TB-16D.

The Akula uses the Pelamida towed array. Empirical testing indicates testing ranges  on the order of 20,000 yards.

 

The Towed Array (TA) is the primary detection/TMA/attack sensor. The sonar processor gives mirror images. Each contact has two traces. You can use the bow array differentiate which trace is the true trace as the bow array shows only the true trace. You can further differentiate by simple listening. Further, when you click on both images TMA will only assign a tracker to the correct one. Your ships’ sonar operator often calls out contacts and bearings listen to him. If he was “Torpedo in the water bearing 300” and you look to sonar and see a trace at 300 and 120, figuring the TIW is the 300 trace might be a good call here.

 

ACTIVE INTERCEPT

 

   All platforms have a final passive sonar system, the WLR active sonar intercept. This sensor detects active sonar signals and will provide you with a bearing, time between ping intervals, time elapsed since last ping, sonar frequency and a rough signal strength expressed in colored lights at the bottom of the display. Using the information in the USNI reference you can cross index a frequency with a platform type to classify the source of the active sonar. Primarily this is used for active torpedo evasion (covered later in its own section). It is also possible to track vessels that are actively pinging my marking the bearing to each ping.

The following gives a pictorial feel for the passive sonar capabilities showing arcs of detection and approximate ranges. Note that the ranges can be dramatically affected by environmental conditions as well as ship class.

 

 

 

 

ACTIVE SONARS

 

 

SPHERICAL ARRAY

 

   Active sonar is the use of a device to send a signal out into the water and then listens for a reflected signal from a target out there returns to the ship.  This is commonly known as “The Ping”.  Most divers rarely use it because it does give your position away and with two or more enemies they can triangulate your exact position in seconds. However active sonar does have its uses in certain combat situations.

 

While the ping does give away the active boat, it also can provide an exact location for an enemy ship.  More than a few ship drivers were overjoyed at hearing an active ping, now giving them a bearing to the enemy they had been searching for over the last hour, only moments later to be very surprised when an enemy weapon eats them. Active sonar does give away the bearing to your boat and it also can precisely locate an enemy. This last point has to be remembered. If you hear a ping, there is a good chance you are painted on someone’s sonar screen as a bright green dot.

 

The speed of sound in seawater is about 1700 yards per second.  When you ping the ping wave moves out that fast. Your maximum range is 80,000 yards (40 miles). At 1700 yps it takes 47 seconds for the ping to get out there. THEN, 47 seconds for the return echo. This is the often forgotten part.  By the time the transmitting boat hears the return ping the target can have up to 47 seconds to do something.  A ship at 30,000 yards, a more realistic combat range, has 18 seconds warning that he has been pinged before the active boat gets a return. In 18 seconds a combat diver can shoot a pair of snap shots easily and since these are fired  “after“ the ping they will not appear on the active return.  If you ping expect the return signal to have a little something riding behind it for you.

 

Active sonar is somewhat bottom dependent. A hard bottom acts as an excellent reflector and can give you a cleaner return at long range. One useful trick is to put a slight down angle on the ship just before going active.  For distant targets, say 60,000 yards or so, it can give you a much cleaner and brighter return. Mud bottoms degrade sonar. A slight up angle can help with long-range resolution in this case.

 

You can and will get false returns from active for all sorts of reasons, a piece of junk on the bottom, a barnacle on your sonar dome, dead torpedoes from previous firings.  You have to sort out the screen and determine what could be a target, and what is not. This leads to the next item, combat sonar technique.

 

If you know only the general area of a target, active sonar can help you make the kill. Fire two slow “over the shoulder“ shot weapons towards the general area.  When they get to the general zone, go active on your sonar.  Your active return will show your own torpedoes and you know where they are from the plot.  From that you can judge the other returns. A sub will be bigger and brighter than a return from a torpedo.  If you timed it right, the return from the target will give you a precise location. Then you merely steer your close by fish to it and enable them. Targets get very surprised by this. They hear faint fish (long ways off…must be.. no sweat)…one ping (ah ha!! I got him) and 60 seconds later an enemy torpedo banging away close at hand  (Holely Underwear!… where did that come from?). This technique is deadly effective and most useful in shallow water combats. For Akula drivers, the SS-N-16 “Sea Stallion” gives a missile/torpedo standoff range of 27 nm. Getting an active return you can drop an SS-N-16 on it without waiting. Be aware though, the SS-N-16 has a small warhead and you can be detected on firing it.

PING STEAL

 

   A very useful technique for active sonar is called the "Ping Steal". In this you use the enemy active sonar to locate the enemy ship. It works as follows. When you hear a ping, note the line of bearing. Then proceed on a course at right angles to that line of bearing at as high a speed as you can safely go while listening.  The odds are very good that the enemy will ping again because a single ping except at close range generally does not give a good tactical picture. On the second ping note the bearing. Now draw both bearing lines and where they cross, is the enemy vessel. You have used the enemy active sonar, "stole" his ping to get a precise location on him. The higher your cross bearing speed between pings the better the cross bearing fix will be.

 

HIGH FREQUENCY SONAR (HFS)

 

The HFS is sail mounted active sonar of very high frequency and limited range.  Its detection range is 6000 yards. It will display 60 degrees to either side of the bow but it can detect 90 degrees to either side. Because of its high frequency it is not detectable by other vessels. The manual states its primary use is for detecting mines as well as under ice work and it does work well for this. However, it can also detect torpedoes and is extremely useful for this when evading an incoming weapon (see section on HFS spin).  It can also prove useful for station keeping maneuvers on another vessel within 6000 yards, a merchant you are hiding under for example.

 

FATHOMETER or DEPTH SONAR

 

   This sonar is a small, high frequency active transponder that provides depth under keel information. It has its own selection display, and will show the keel depth over the last hour on an X-Y display, and the current depth under keel. The graphic display has variable selections for the depth display. This sonar is on all the time and used to let you know where the bottom is in relation to where you are.

 

 

SURFACE SENSORS

 

 

RADAR

 

    The first of the electronic surface sensor is the boat’s active radar. To use it you must be at 58 feet or less (688(I)) 62 Feet or less (Sea Wolf) 14 meters or less (Akula) and below 5 knots (if using it submerged).  The radar sends out a microwave pulse and listens for a return echo from the target.  It has a range limit of eighty miles, and within that range can detect something as small as a periscope and has even given faint returns on shallow running subs (periscope depth) and torpedoes under the right water conditions.  Use of radar does give away the emitting ship but only if the target has its ESM detector out. Radar will give fairly precise ranges and bearings to contacts.

 

ELECTRONIC SURVEILLANCE MEASURES

 

    Electronic Surveillance Measures or ESM receiver is a mast raised from the radio room to passively listen for any and all active electronic emitting systems. It will detect a signal and show it as a bearing spike to the contact on a CRT in the radio room. If you move the moveable cursor onto that spike it will also classify the platform emitting the signal. You can further select the ‘mark” button and it will give you a rough range to the contact based on the type of radar and the signal strength detected.


PERISCOPE

 

    Your ship has a periscope for visual sightings out to a range limit of about 22,000 yards (based on the curvature of the earth and height of eye for a scope at periscope depth). It has adjustable magnification settings, a low light level boost system for night viewing and can be inclined upward for aircraft detection as well. It can provide a bearing to a target and using the built in stadimometer can provide a fairly accurate range as well.  This can be automatically sent to the TMA plot system. The periscope can be deployed and operated from a maximum keel depth of 70 ft and at a maximum safe speed of 10 knots. This sensor is of limited use for subsurface warfare but damaged subs can surface and this when the periscope can prove to be lethal.

II.  UNDERSTANDING SONAR

 

   SOUND-VELOCITY PROFILE (SVP).  — A sound-velocity profile is simply a graphic representation of speed versus depth. Sound-velocity profiles are constructed from sound-speed nomograms based on temperature, depth, and salinity.  They can also be constructed from bathythermograph soundings. An SVP provides surface sound speed, depth of maximum sound speed (sonic-layer depth), and layers where sound travels great distances (ducts and sound channels).

 

           Basic sound-speed structure of the deep ocean.

 

Sonic-Layer Depth (SLD).  — The sonic-layer depth is the depth of maximum sound speed. The SLD can be determined from a BT trace.  A negative-temperature gradient (temperature decreasing with depth), within certain limits, compensates for an increase in sound speed with depth due to pressure; this results in a constant sound speed with depth.  These gradient limits per 30 meters of depth are as follows:

 

The SLD can be determined from a BT trace by considering the following criteria:

 

1. If the maximum temperature is at the surface, and the gradient is more negative than the limits listed, the SLD is zero.  It’s at the surface.

2. If the BT trace is isothermal or has a slight negative gradient (less than the stated limits) and then becomes more negative, the SLD is at the bottom of the isothermal or slightly negative gradient layer.

3. If the maximum temperature occurs at a depth other than the surface, this is the SLD, unless the gradient below depth of the maximum temperature is less than the stated limits.

 

 Outgoing ping showing shape of beam pattern and divergence of sound rays.

Sound Paths

 

As sound energy leaves a sound source it travels in waves.  The sound waves expand as they move away from the source.  A sound wave’s path of travel is dependent on its speed and any matter in its path.  Sound, like light, is refracted, reflected, and scattered.

 

REFRACTION.  —As a sound wave moves through the sea, it travels along a curved path.  The path is curved, because sound speed varies along the wave front.  Sound waves bend (are refracted) in the direction of the slower sound speeds.  The greater the change in speed over a given distance or depth, the greater the refraction.  The gradient is a function of speed versus depth or distance.  For example, in a layer of water where sound speed decreases rapidly with depth (a strong negative-velocity gradient), sound waves bend sharply downward.  Sound rays refract upward if sound speed increases with depth (a positive-velocity gradient). The BT sounding and SVP which bring about these paths accompany each pattern.

 

Straight Rays.  —Sound rays travel in straight lines only where the speed is everywhere constant (isovelocity); no change in velocity with depth.  Straight sound rays occur when the temperature profile is slightly negative.  Long sonar ranges are possible when this type of profile exists.

Representative sound patterns based on temperature and sound-velocity gradients.

 

Rays Curved Downward.  —A negative-temperature gradient (temperature decreasing with depth) produces a negative-velocity gradient.  The sound rays leave the sonar and are bent downward, thereby limiting sonars to very short ranges. This is a common occurrence in the near-surface layer.  Beyond the range of the downward bending sound rays, sound intensity is negligible.

 

This area is known as a shadow zone.

 

Rays Curved Upward.  —A positive-temperature gradient causes sound speed to increase with increasing depth, and sound rays to refract upward.  Longer ranges are attained with this type gradient, especially if the sea is relatively smooth.  As the rays bend upward and strike the sea surface, they are repeatedly reflected to longer ranges.

 

Split-beam Pattern.  —A split-beam pattern occurs when the temperature gradient in the near-surface layer is isothermal, and negative below.  Sound rays from sonar split at the depth of the gradient change.  Part of the sound rays are refracted upward toward the surface, and part are refracted downward toward the bottom.  At the point where the rays split, a shadow zone exists.  A submarine operating at the split depth improves its chances of avoiding detection.

 

Sound Channel.  —A sound channel occurs when a negative-velocity gradient overlies an isovelocity or positive-velocity gradient.  The depth where the velocity gradient changes from negative to positive is the axis of the sound channel.  The axis is the level of minimum sound speed.  The sound rays on both sides of the axis travel faster than the rays in the center.  And since sound refracts toward slower sound speeds, the faster rays are continually refracted toward the axis.

 

REFLECTION.  —Sound waves that strike solid surfaces have all or a portion of their energy redirected or absorbed.  The surface or object struck determines if the sound energy is reflected, scattered, or absorbed.

 

Reflected sound energy can be good or bad.  The type or quality of reflected sound is dependent on the surface from which the sound bounces.  For example, a smooth hard surface is a good reflector.  Sound waves bounce off such surfaces like a mirror and lose little of their energy.  An irregular hard surface is not a good reflector.  The sound waves are reflected in many different directions and lose a good deal of their energy.  This type of reflective energy loss is known as scattering.

 

Sound energy in the sea is scattered by the sea surface, sea floor, and suspended matter. Because the sea surface is rarely smooth, it is more apt to scatter sound than to reflect it.  A rough or rocky bottom also scatters sound energy.

 

In contrast to these rough surfaces, a smooth rock ocean bottom is perhaps the best reflector of sound in the sea.  A smooth sand bottom also reflects sound very effectively.  The sea surface, if it is calm, is also a good reflector.

 

REVERBERATION.  —Reverberation is noise or interference at a sonar receiver, which makes target detection very difficult.  This interference is caused by scattered sound energy being reflected back to the sonar receiver.  There are three types of reverberation: surface, volume, and bottom.

 

Surface Reverberation.  —Surface reverberation is a product of surface wave action.  At short ranges, surface scattering increases with wind speeds.

 

Volume Reverberation.  —Volume reverberation is caused by reflectors in the water such as fish, marine organisms, suspended solids, and bubbles.  Volume scatterers are not uniformly distributed in depth, but tend to be concentrated in a diffuse layer known as the deep-scattering layer. The intensity of the scattering is a function of sonar frequency (some sonar frequencies are affected to a greater degree than others) and the density of the organisms in the layer.

 

Bottom Reverberation.  —Bottom composition and roughness govern the degree of reverberation that contributes to the masking of target echoes.  The amount of bottom reverberation is directly related to the roughness and composition of the sea floor.  Another problem created at the ocean bottom is one of absorption.  When the bottom is composed of soft mud, sound energy is absorbed.

 

ATTENUATION.  —Attenuation is the energy loss that occurs in propagated sound waves due to scattering and absorption.

 

ACTIVE AND PASSIVE SONAR

 

Sonar was originally designed to assist surface ships to navigate in bad weather.  Later, it was employed on submarines and today it is our primary means of locating submarines.  There are two types of sonar searches: active and passive.  Active sonar employs a transmitter to send out sound pulses and a receiver to record returning echoes.  Passive sonar listens for sounds generated by other ships and submarines.

Active Sonar

 

Active-sonar search is classified into two modes: shallow-water transmissions and deep-water transmissions.  The essential difference between shallow- and deep-water transmissions is the interference effects produced by the multiple reflections of sound in shallow water.

 

Shallow water is classified as water less than 100 fathoms—that is, water over a continental shelf.  Deep water is classified as water 1,000 fathoms or deeper.  Water between 100 and 1,000 fathoms deep is most common over continental slopes.  It is not considered overly important in active sonar operations because it exists in such a small portion of the world’s oceans.

 

SHALLOW-WATER TRANSMISSIONS.  — Shallow-water propagation paths are classified as direct path and surface duct.

 

Direct Path.  —Direct path is the simplest mode.  Direct path sound propagation occurs where there is an approximate straight-line path between the sound source and the receiver, with no reflection from any other source and only one change of direction due to refraction.

 

Surface Duct.  —A surface duct is simply a near-surface layer that traps sound energy.  Surface ducts exist in the ocean if the following conditions are met:

 

1. The temperature increases with depth.

2. An isothermal layer is near the surface.

 

In condition 1, sound velocity increases as the temperature increases.  In condition 2, there is no temperature or salinity gradient; however, the in-crease in pressure with depth causes the sound velocity to increase with depth.

 

The greater the depth of a duct, the greater the difference between the surface velocity and the velocity at depth.  There are also a greater number of sound rays trapped in the duct.  The efficiency of a surface duct in is dependent upon the smoothness of the sea surface.

 

ENVIRONMENTAL CONTROLS.  —The success of active sonar searches in shallow water depends a great deal on environmental factors.  Temperature gradients, horizontal as well as vertical; water depth; and the physical characteristics of the sea surface and bottom all impact shallow-water transmissions.  Of these controls, water depth is the most important.  Water depth determines the range and angle at which sound rays strike the bottom (angle of incidence) and to some extent the types of transmission paths that occur.  Variations in the vertical temperature gradient, which result in sound speed variations, are of utmost importance where sound is propagated through a surface duct.  A small change in gradient can be the difference between an excellent duct with good ranges and no duct and poor ranges.

 

Horizontal velocity gradients in the ocean are not as great as those in the vertical; however, they can completely destroy a duct if they occur between the sound source and the target.  Bottom composition and roughness control the reflective and absorbent capabilities of the bottom.

 

DEEP-WATER TRANSMISSIONS.  —In deep water, sound may travel from and to a sonar via surface duct, convergence zone, bottom bounce, and sound channel transmission paths.

 

Surface Ducts.  —Surface ducts occur in deep water just as they do in shallow water.

Sound Channels.  —A sound channel is formed when a negative-velocity gradient overlies a positive-velocity gradient. The sound channel axis is found at the point of sound-velocity gradient change.  The axis is the point of minimum sound speed.  Sound channels trap sound rays and provide extremely long ranges.

 

Shallow sound channels are found in the near-surface layer.  They are rare and transitory (they move), and occur when thermal conditions are unstable (cold water over warm).

 

Deep sound channels are far more common than shallow.  In the deep ocean, temperature generally decreases with depth (the main thermocline).  This produces a negative-velocity gradient and sound rays that refract downward.

 

Convergence Zone.  —This sound transmission path is based on the principle that sound energy from a shallow source travels downward in the deep ocean and is refracted at depth.  The refracted rays travel upward and reflect off the surface about 30 miles from the sound source.  The reflected rays travel downward, and the pattern repeats itself.  The sound rays reappear in the surface layer at successive intervals of about 30 miles out to several hundred miles.

 

There are two conditions necessary for convergence zone transmission: (1) The sound velocity at depth must be equal to or greater than the sound velocity at the surface and (2) the water depth below the deeper sound velocity maximum must be great enough to permit the refracted sound rays to converge in a small area at the surface.

 

The three transmission paths just discussed depend upon the restrictive conditions of the velocity profile and the depth of the sound source and receiver.  Thus, if velocity gradients are ignored, path predictions are not possible.  The fourth path can be predicted roughly without considering gradients.  This path is the bottom-reflected path, commonly termed bottom bounce.

 

Bottom Bounce.  —Bottom bounce transmission uses angled ray paths to overcome velocity gradient changes.  The sound energy is directed downward at an angle.  With steeply inclined rays, transmission is relatively free from thermal effects at the surface, and the major part of the sound path is in nearly stable water.  The sound energy is affected to a lesser degree by velocity changes than the more nearly horizontal ray paths of other transmission modes.

                                          -Deep-water sound-transmission paths.

 

Long ranges can occur in water deeper than 1,000 fathoms, depending on the bottom slope.  It is estimated that 85% of the ocean is deeper than 1,000 fathoms, and bottom slopes are generally less than or equal to 1 degree.  On this basis, relatively steep angles can be used for single bottom reflection to a range of approximately 20,000 yards.  At shallower depths, multiple bounce paths develop which produce scattering and its high intensity energy loss.


III.  SIX MINUTE RULE

 

The “Six Minute Rule“ is a rule boat drivers live by. Take the speed of anything in knots, multiply it by 2...then add two zero‘s at the end of it. This is the distance in yards the object will travel in six minutes.

DISTANCE (yards) travelled in 6 minutes =  SPEED(knots) × 200

For a weapon travelling at 55 knots, 55x2 is 110, and putting two zeros at the end of it, is 11,000 yards.  That is how far the weapon will travel in six minutes. The range to hear a torpedo ram fire is on the order of 8-12 kyards. So if you fire and are heard counter fire will eat you in roughly six to eight minutes. Now then suppose you fire and evade at 5 knots, a nice, silent speed popular with the Sea Wolves. 5x2=10 and with the two zeros, is 1,000 yards. The active acquisition cone of an TORPEDO is 5,000 yards in diameter. In other words, you are dead against that weapon.

If you shoot, shoot and scoot. Fire on a lag LOS (LOS =3D Line Of Sight, explained in detail a bit later) and then expect counter fire in roughly seven minutes. You have to be at least 2,500 yards away (half an acquisition cone) before that time or you will be acquired. 2,500 yards, working it backwards is 12.5 knots (call it 13) for six minutes. That is the speed at right angles to the firing LOS you have to use to ensure you are not snapped up. It works and works very well. By the time they can TMA your speed and range, you are out of the cone.

 

IV.  ACTIVE WEAPON EVASION

 

Active weapons have an acquisition range, of between 2,000  (SS-N-16) and 6,000  (TORPEDO) yards depending on sonar conditionsand weapon type. If you see an active pinging and it is green or the first yellow light on your active detector it does not have you yet. Change layers, and set an opening course. Keep your speed about ten to fifteen knots and see what happens. A layer change drastically reduces weapon acquisition efficiency and you can skate right past it if you use this (sometimes). Do not pour on the coal unless you have to because a flank bell knots is a beacon to the bad guy‘s sonar.

If it does snap you up and you are getting red returns and a ping rate of 2 sec or less then go to flank. Let the speed build to about 30 knots, then change course hard 90 degrees to the bearing of the weapon. You can out turn an incoming weapon. By the time it circles to reacquire you are at flank and screaming off. Fire CMs at the turn. When the weapon circles you have a better than 50% chance it will go for the decoy.

A lot of commanders try depth changes initially. Be careful here. A weapon can change depth faster than a submarine and it will ride right up or down with you.  A large depth change AFTER the evasion turn is a good idea if you have the water for it. The cone is three dimensional and this evasion uses that fact. Keep in mind a big depth change will slow you down more than a radical course change, and the slowing can be fatal. If a layer is close to your depth then a slight depth change on each course variation to get to the other side of the layer can shake off the weapon.

If all else fails and it is very close fire a spread of CMs, go to your ship controls page and manually grab the rudder and move it 30 degrees away from the line the pings are on. Hold it until you have turned 90 degrees and then center the rudder. Then change depth as much as possible while preventing cavaitation (if at TEST DEPTH, go to 550. If shallow, go to TEST DEPTH).  This is a desperation move. The sharp turn is more than an incoming can do and a radical depth change right after combined with the CMs in the water has an even money bet to get you clear. Watch that turn. You can turn right into it if not careful and it takes only a couple seconds miscalculation to do this.

V. TORPEDO PRESETS

 

Torpedo presets. What are they and why? Your fire control officer rarely gets them right, so this is something to watch for. Many of you saw the movie “Hunt for Red October“. In it, they referred to “Weapon Safeties“. Those, are your presets. They are floor, ceiling, run depth, active/passive, run to acquisition, speed and bearing for snap shots. Real Life operations, do not allow subs to “Enigma“ each other and it is considered poor form to destroy boats on your own side.  Ceiling, is a depth the torpedo will not go above. It is to protect surface ships (like a convoy you are escorting) primarily when a sub versus sub combat is going on. It can be used for top protection also for subs you think might be good guys but have not yet identified. It would be something along the lines of all US boats stay above 300 feet east of Cyprus (an actual order once). Any boat deep is a bad guy. If you fire and miss the weapon cannot kill a good guy, if you put a 300 foot ceiling on it under those conditions. The floor has the same effect giving protection on the bottom side rather than the top. Floors also can prevent your weapon from burrowing into the mud in shallow waters.

RUN DEPTH, is tricky. For shallow water operations you set the run depth to prevent the torpedo from borrowing into the bottom. Check the projected depth for the entire weapon run (chart work here) and pick a run depth above it all (note: set your floor above it all also).  Shallow run depths makes it noisy but gets it above layers.  A deep run muffles the torpedo noise making it harder to detect. So, decision time. In general, run weapons deep as you need to get as close as possible before the bad guy hears the torpedo. Run depth, is the “post enable“ run depth. When you fire a weapon, it runs at whatever depth your boat was at when you fired. One useful trick if you are shooting from a hole is to manually enable the launched torpedo  for a second and then post enable. The weapon will go to the required run depth then and stay there and if you are fast on the enable switch it will not make a single ping doing this (assuming active weapons). This has been used to great effect by boats in deep holes. They fire and then have the weapon “pop up“ to a shallow run depth to target all without exposing the boat to counter detection.

ACOUSTICS (Active/Passive) is just that. The Sub Command  Manual talks about it. One thing the manual does not mention is that the active acquisition range is about twice the passive acquisition range for all classes of weapons. You need a very good firing solution for a passive hit. Active is much more forgiving. Passive does not give the weapon position away, making evasion of it more difficult. This topic will be covered in more depth a bit later.

SPEED is a very misunderstood setting. Normal speed is 55 knots which gives you  about 50,000 yards reach. A slower weapon speed increases the weapon range, (about 54,000 yards at 35 knots). For long shots you will need this reach. What the manual does not tell you is that these are pre-enable speeds. Once the weapon enables and acquires a target, it goes to 55 knots no matter what the setting. So you can catch a running boat even if you pre-set for 35 knots.  Running shallow will also give great range. For a long shot at a submerged target fire it from 100 feet even though you truly know the target is at 1,000 feet.  Set the enable run depth for 1,000 feet. This can buy you about 2,000 extra yards of run. When the weapon enables it will dive to the depth needed for the hit. One other side benefit is that slower weapons are slightly quieter and therefore harder to detect. It is much easier to get a kill with them.

ENABLE range, is the distance the weapon goes before it enables internal weapon tracking and for an active weapon pinging. You want to pick this range to enable as close to where you think the target is as possible to minimize the chance of target evasion. However if you misjudge and enable behind the guy the weapon will never see him. You can override this setting by toggling  “pre-enable“ on the weapon steer page. The torpedo is now a bullet and will run until you manually enable it or it runs out of gas. A good trick here is to manually enable short of the target (this for active weapons) and watch sonar.  If the target bugs out and most will when they get pinged on, watch the target course (trace direction on the array) and that can give you a rough idea of range (faint...far away, bright...close).  Then and here is the nasty part, pre-enable it again. Now the target thinks the bullet is dodged and in a minute will slow down. You sonar/TMA should have an excellent range solution from all this.  Steer the weapon to the target and re-enable close. You should get a hit.

VI.  LINE OF SIGHT (LOS) and TMA

 

   The LOS is an imaginary line between you and the target. If you could see through bulkheads and looked in that direction with super eyes you will see the target. Take a piece of paper and draw two dots. This represents the actual locations of your boat and the target. Now connect the dots with a line. This line is the LOS. Now comes the tricky part. On your dot, a couple of inches up the line, write the bearing to the target (320 degrees, for example, target is NW of you.) Now from that line at the dot where your ship is use a protractor and draw a line from the dot along your ship‘s course. Now you have a line to the target and a line showing your ship‘s course. If you were going course 000 then the line you just drew is 40 degrees to the right of the line going to the target.

(320)

            Target   X

                     :

                     :

                     :

                     :         (000)

                     :       / Line showing course.

                     :     /

                     :   /

                     : /

             You     Y

 

Okay, nothing to it. All this stuff you have. Now what about the bad guy? You have no idea of  the course and speed are but you have a bearing, in this case 320.  Now...a minute of two goes by under these conditions. You read his bearing which is now 318 degrees. The enemy is drawing to your left. Now I will use a dirty word: Vector. Vector is the component of your speed going in a certain direction. If you were at 10 knots in this example then some of that 10 knots is pointed at the bad guy and some of that 10 knots is moving at right or left angles to the bad guy. The component moving at right angles is the Sine (pronounced “sign“...honest) of the angle between your course and the enemy bearing (360-320 in this example) times your speed. So here, 10 x Sin 40 = 10 x .642 = 6.42 knots.  Don‘t worry about the component of speed going towards the enemy  (7.66 knots in this case....ye ole Pythagorean Theorem at work) as it is not important just now.  Now....

(320)

            Target   X

                     :

                     :

                     :

                     :         (000) at 10 knots

                     :       / Line showing course.

   7.7 knots =:     /

                     :   /

                     : /

             You     Y - - - -  = 6.4 knots

 

You know you have a 6.4 knot cross vector to the target and the bearing rate is drawing left  (320.....319.....318...). The only component of the left/right business is your 6.4 knots and whatever left/right component (s)he has. Since (s)he is drawing left your 6.4 knots right component is bigger. It has to be for the other boat to be moving to the left. Great. You have just made a bracket of course and speed for the bad guy. If the enemy were also moving at 000 degrees at 10 knots the bearing to the enemy would never change but you know it is. Therefore, the bad guy is a lot slower than you are overall or the course allows only a tiny right/left component like if (s)he was on course 140 and coming down your throat.

For real you can maneuver the boat to the other side of the LOS (course 270 say) and watch how things change. Using the same math you can very quickly get his course, speed and probable range. Your TMA computer does this for you. If you are drawing to the left (or right) faster than the other guy, this is called a “LAG LOS,“ meaning simply the other guys right/left vector lags yours. If he is drawing left or right faster than you this is called a “LEAD LOS.“ All you have to do, is look at the trace on you sonar. Line left, line right, line straight. You want the bearing line to be turning away from your course, a LAG LOS, also called going to the LAG, BEFORE you fire. That way when you fire the enemy hears it and counter fires (bet on it)  the enemy weapon will pass harmlessly behind you as you are off that bearing now. If you fire from a LEAD LOS, enemy counter fire will continue to lead and very likely snap you up.  Whenever possible always...always..ALWAYS...fire from a LAG LOS.
VII. FLEET OPERATIONS

Fleet operations are combats where you enter the dive with one or more boats on the same side with the objective of locating and destroying an opposing group of boats. You must use coded communications between boats on the same side. Boats will enter the scenario scattered so location information to your wolf pack commander is critical so that he or she can plan a strategy.

The big advantage in diving with a wolf pack is the ability to use coordinated attacks and triangulation. If for example, you hear a firing bearing to an enemy weapon (Conn, sonar: Torpedo in the water bearing 145) you have no idea of the location of the firing boat. However if your teammate hears a similar report then ask him/her for the firing bearing that was heard. If you have the locations of friendly boats and you should by weapons free time, then go the  charts and draw the line you heard and the one your partner heard. Where they cross is where the bad guy is. In seconds you have an accurate firing solution needed to set weapon enable range. Now fire and evade and your weapon has an excellent probability of getting a hit. If you give the bearing to your teammate when he/she gave it to you then that person can also fire at the target. The different angles of fire will effectively put the target in crossfire and virtually guarantee a hit.

A standard fleet tactic, is “Bounding Overwatch“. Overwatch is used generally in a transit situation. In it one boat moves forward at 10 knots for about 15 minutes while the other boats sit and listen ghosting along at 1 or 2 knots. After 15 minutes the boat at 10 knots drops to 1 or 2 knots and the boats behind move out at 10 knots for 30 minutes...then drop to 1 or 2 knots and the last boat in the chain move out at 10 knots again...and so on. The 10 knot boat is the probe. This boat is moving fast enough to make distance but slow enough to listen. This is the “Bounding“ boat. The boats at 1 or 2 knots are the “Overwatch“ killers. Anything detected by the 10 knot boat or shoots at the 10 knot boat and the “Overwatch“ boats kill it. Variants of this technique can adjust speed (15 knots for example) and number of “Bounding“ boats and  “Overwatch“ boats as needed for the specific tactical situation.  The only caveat is to make sure the “Bounding“ boat is within weapons coverage of the “Overwatch“ boats. Never let it get more than 11,000 yards from coverage (about six minutes weapon run) or it will be unsupported. Properly employed this technique can make good time in a transit and drive the bad guys nuts as targets appear and disappear on them.

A second tactic used from time to time is “Hare and Hounds“.  In this tactic one boat, and it should be the best driver, screams out at 25 knots or so into a suspected bad guy zone. The other boats stay real quite and pretend to be holes in the ocean. The fast boat, is the “Hare“. Bad guys will see him and fire giving away their positions. The quiet boats (the Hounds) counter fire at the bad guy positions. It is very possible that the bad guys will use double shots at the Hare leaving empty tubes facing the Hounds with incoming driving at them. Now to evade the Hare will have to crank to flank bells making passive sonar useless. “Hound“ boats will have to try and help the Hare with their sonar so (s)he can evade. This maneuver requires a lot of trust and skill and should not be used with inexperienced boat drivers. Properly employed you can take out an enemy wolf pack without a single loss and this can be and has been done. This tactic is not one to employ unless nothing else works as it is a high risk maneuver for the Hare boat.

One help on either tactic is the “over the shoulder“ shot.  To employ this technique face your boat away from the enemy 180 degrees so your tubes are facing away. Then use presets to fire two slow fish (40 knots) away from the enemy and with the deepest run setting you can manage. Wait a few minutes and then turn the weapons 180 degrees towards the enemy. Then wait for the Hare boat to flush them out and steer your weapons accordingly. This gives the Hounds a number of advantages. Facing away the enemy will not hear your torpedo ram fire. Setting the fish slow and deep makes them very quiet so you can drive them in close without their being detected by the enemy boat‘s excitable sonar operators. Facing away from the enemy lets you use your towed array, by far your best sensor, to scan for the enemy and steer your fish. Finally, if you miscalculated the maneuver facing away puts you in a good position to evade incoming. 


VIII.  FLEET TRIANGULATION (Homer Plot and Grid)

 

This section is thanks to VADM Homer who developed it. This is the principle of deducing an object's approximate location based on bearing contacts from two or more submarines.  The minimum information needed for a triangulation plot is the map positions of at least two members of a team and both of their sonar bearing to the same contact. 

 

 

HOMEPOINT

 

The concept of home point is supplemental technique to traditional plotting.

 

The team leader establishes a random or neutral point on map and mark it then communicates its location to the rest of the team. To plot with this method, you note an object's range and bearing from the home point using the ranging ruler. You relay this information to your team, expressed in terms of range and bearing from home point, instead of longitude and latitude. This reduces the time spent on searching for a specific longitude and latitude.

 

This method is best used to plot your own sub's location to relay to your teammates because as you all know, the exact location of another sub is rarely known.

 

 

HOMER’S TRIANGULATION PLOTTING

 

Several plotting methods can be used to triangulate an object's position during a team dive. The most popular method is to use pen, paper, protractor and a calculator.  Another effective method that has been devised is to use the Tomahawk course waypoint markers as a plotting tool.

 

Using this method has several advantages over the others: First, it is quick and easy to use.  Second, it overlays onto the game map, a visual representation of the triangulating lines in addition to your teammate's location.  Third, it allow for rapid plotting of longitude and latitude information, simply by typing the numbers.  These advantages will save precious time at crucial moments and increases your team's overall situational awareness.  The limitation of this method is plot accuracy with an error factor of +/- 2000yds.

 

Each Tomahawk waypoint marker will be referred to as WP1, WP2... WP4. WP1 is the marker closest to your sub and W4 is the final waypoint marker. To position a WP marker on the map, you select WP by first clicking on it, then you may either drag and drop it to another location or you may enter the new longitude and latitude coordinates into the text box next to the map.

 

 

Before you begin a plot with this system, a home point (HP) should be established. Select WP2 and position it on the HP location. This is best done by inputting the HP longitude/latitude data directly into the text box. This step only needs to be done once.

 

 

Next, select WP4 and position it on your teammate's location by inputting his longitude/latitude information into the text box.

 

 

 

WP1 is used to plot your bearing to contact and WP3 is used to plot your partner's bearing to contact.  To position these, you drag and drop the WP marker.  The procedure is as follows: To position W1, you place the cursor in the center of your own sub icon on the map, press R to call up the ranging ruler, move the cursor to the center of WP1, click and hold down left button, move WP1 to the bearing of the contact from sonar using the bearing readout from the ranging ruler. Move WP1 at least 30nm away to account for all the possible range to the contact.

 

 

 

Now do the same for WP3, your partner's bearing to the contact.  Remember to also move WP3 at least 30nm away from WP4 to cover all possible range.  You should see the WP4-WP3 line and the Own Sub-WP1 line intersect at some point on the map. This is the location of your contact.

 

 

Triangulating plots on additional contacts and/or with third or more teammates can be concurrently done by using additional TLAM waypoint course markers.

 

HOMER’S GRID SYSTEM

 

This system has been developed to assist teams to coordinating their fire control and to help plot the enemy submarine locations. This grid system is designed to augment Homer’s Triangulation Plotting system, but can be an effective standalone tool for team missions.

 

First step is go to Navigation station and call up the map grid by placing the cursor on the map and pressing G. Set the map resolution to 5 or 10nm.

 

 

Next step is to designate the Homepoint and place the Navigation Aid Markers relative to it onto the grid, 10nm apart from one another.  These are to be used as points of reference.  The grid is best set up with the enemy location close to the center marker.

 

 

 

Each row (horizontal) and column (vertical) is to be referred to accordingly:

 

 

You communicate a position on the grid to your teammate(s) by expressing coordinates in terms of columns and rows.

 

  Syntax: <COLUMNS (LETTERS)> - <ROWS (NUMBERS)>

 

Using this format each given coordinate can denote an individual cell (a single 5x5nm square), a group of cells, or a complete row/column.

 

  Examples:

Example 1.  A-4

Example 2.  C-456

Example 3.  DE-23

Example 4.  0-1  (A zero is used to represent a complete row or column)

 

The purpose of this grid system is to provide a simple and easy to use method of exchanging information among team players.  The grid system is not as cumbersome to use when compared to other existing methods in use for team dives.

 

Some practical applications of this system are as follows:

 

(1)        General plotting of enemy location and movement.

 

“Contact is in E-4 and moving eastward into F-4”

 

(2)     Coordinating team members’ torpedoes.

 

“Contact is possibly in D-34: set your torpedoes to come in from the west and I will set mine to come in from the east”

 

“I think the enemy is in C-0… fire up B-0 and turn a torp east on each odd row and I will fire up D-0 and turn a torp east on each even row”

 

“Where are your torpedoes at? ”

“They are in AB-2 and heading north”

IX.  COMMUNICATIONS

 

Older Submariners will recall that the order “Dive, Dive, Dive” from the bridge down a voice pipe was changed to “Dive the Submarine” when on one feet-wetting occasion, the order to “Steer 355” was misinterpreted.

 

   With the advent of voice communications correct and accurate communication is now a critical issue in Fleet Operations.  The first thing to always keep in mind is that voice communications is NOT a telephone.  With more than two people in contact and with the varying voice quality conditions of the net it can be next to impossible to tell who is talking. People talking often forget that the information they are passing has to be written down by the poor task group commander and speak so fast he or she has no time to record it.  Commanders are not in the habit of repeating back what they have heard so if they get it wrong there is no second check available. Errors of this sort generally are fatal. So then, to correct this and insure that the RW program, or any combat related voice program, is in fact an aid to combat operations the standard Navy radio protocols will be followed:

 

1.        Learn the phonetic alphabet  (A=Alpha, B=Bravo, and so on….it is on the Net….get it) and USE it.

 

2.        Never state a number as a number, but instead sound each digit individually (hundreds can be done as a group). If you are 34-19 north and 54-23 west…then state, “Mike Lima THREE FOUR DASH ONE NINER NORTH, FIVE FOUR DASH TWO THREE WEST“.  Note….Mike Lima means (M)y (L)ocation..phonetic alphabet again.

 

3.        ALWAYS start EVERY transmission with who you are talking to…and who you are, “Roger Rabbit this is Briar Patch, Mike Lima THREE FOUR DASH ONE NINER NORTH, FIVE FOUR DASH TWO THREE WEST. Mike Charlie ONE THREE FIVE degrees.  Mike Sierra ONE TWO knots. Mike Delta ONE TWO HUNDRED feet.  This is Briar Patch. Over.“   (Note: Identify at first…give information and identify at end for long transmissions, then state you are done talking.

 

4.        Meanwhile, the team commander was busy scratching his nose and missed part of it… “Roger Rabbit this is Briar Patch. Say again all after Mike Sierra. Over.“  (Note: Short transmissions generally do not need a station identifier at the end.  It is assumed a person can remember at least one sentence worth of information.)

 

5         Now, the new transmission, “Roger Rabbit this is Briar Patch. I say again Mike Sierra ONE TWO knots.  Mike Delta ONE TWO HUNDRED feet. This is Briar Patch. Over.“

 

6          “Roger Rabbit this is Briar Patch. I copy Yankee Lima (Your Location) THREE FOUR DASH ONE NINER NORTH, FIVE FOUR DASH TWO THREE WEST. Yankee Charlie ONE THREE FIVE degrees.  Yankee Sierra ONE TWO knots. Yankee Delta ONE TWO HUNDRED feet. Roger Rabbit this is Briar Patch, out.“

 

Okay, this is wordy, but it makes sure the information is correct. Now…the commander has some options.  Since he or she is coordinating more than one ship, he or she may simply say,   “Roger Rabbit this is Briar Patch. I copy. Over“ and this is fine. It is the team commander’s responsibility to ensure he or she has the information. If he or she is a happy camper with what they heard, then that is that…

 

Group transmissions, are somewhat special. In those, the receivers generally do not repeat back what they heard, but acknowledge receipt only. For example:

 

“All units in Alpha Gulf  (Task Group name Alpha Gulf….not really needed here but will be in sims to come, so best to get use to it now) This is Alpha Gulf  (Task Group commander, always named for the Task Group). All units proceed Charlie TWO SEVEN ZERO degrees, Sierra SEVEN knots, Delta ONE FIVE ZERO feet. Report all contacts. This is Alpha Gulf out.“

Now each ship commander replies:

 

“Alpha Gulf, this is Roger Rabbit. Roger. Out.“

“Alpha Gulf, this is OneGun. Roger. Out.“

“Alpha Gulf, this is DeadMeat. Roger. Out.“

 

Note, they reply in a specific order. Whenever a radio net is set up the stations on it are given an order to reply in for group messages. This prevents people from talking all at once and gives the commander a ghost of a chance at figuring out if everyone heard him or not. For our gaming the logical order would be the diving order of appearance. It is up to the commander to designate the radio reply order and each ship to maintain that order.

 

This sounds a bit cumbersome, and you’re right it is. However it is the basic system in use for eighty years now and it works. Hearing someone yell, “I have a fish on my tail!” in a dive with eight people is useless. Who…where, from what direction? Near or far? And so on.  Without this information the guy with the fish cannot be helped and will likely get killed because he or she was unable to communicate.  Radio discipline will be necessary to conduct successful fleet operations. Speak slowly and clearly…..like you would say to the guy at the Telephone Company who cannot seem to find your paid bill from last month and is going to discontinue your service.  Make sure you are heard. In a Fleet operation, the Fleet Commander owns the radio net.  First and foremost, always give him or her what is needed to insure victory.

X.  PASSIVE TORPEDO EVASION

 

Passive TORPEDO evasion is placed here because it builds upon skills already  developed in this manual.  Passive weapon evasion requires the use of speed and maneuver. To employ these successfully requires the skills learned from “The Six minute Rule“, “Line of Sight“, and “Active TORPEDO Evasion“.

So a weapon is fired. First go to your sonar display. Select the Towed array and look at the trace. Can you see the weapon? If you can it is about 10,000 yards away (14,000 - 8,000 the range it can be picked up at, but 10,000 is not a bad average.) Now assume you can see it. You know the rough range. Next, what direction is the trace going? Picture yourself at the side of a football field at the 50-yard line. The ball is thrown...now...is the ball going left? Assume it is.... Your head is turning left to follow it.  The same thing with the sonar trace...you see it at say, 255 degrees.... then 254...253.....251.... 249....and so on... going left.. The total trace will leave a curve on the screen. Now, just as watching the football moving left is no danger, watch the trace moving left means the TORPEDO is wailing past  you...not at you. In other words it was a bad shot or someone else was targeted.  Okay...now suppose the trace on the sonar is going right? The same principle applies. Going right on the trace, just like the football being thrown up field (Go Navy! Can that Elvis throw or what?)  left to right means it will not hit you, a clean miss.

Well...suppose the trace is drawing a straight line on your sonar. This means the same thing as if that football you were watching before was not moving to the left or to the right, meaning your head is not turning left or right. Instead you are watching the football getting steadily bigger (back to sonar, the trace getting brighter) until it thwacks you in the eyeball  (Ouch!!! Damned Army). If you see a straight line you have got real problems coming straight at you.

So you determined the line is straight and you are the target. Now what? Well, turn your boat opposite the weapon and Go toa flank bell. There is no time for subtlety here. While this is going on note the time you detected the weapon and the time you get to speed. At flank knots your passive sonar is useless,  so you have to time events. Ever wonder why in all those sub movies you always see the officers with  stopwatches? That is real and this is why.

Remembering the six minute rule and knowing you detected the incoming at about 10,000 yards you know you have a little under 6 minutes before impact. However you have cranked up to flank. The weapon  is now closing at 55-(your speed) . This difference is the true closure rate. If it is 12 knots difference, to go 10,000 yards at 12 knots (2400 yrd = 6 minutes at 12…keep this rule in mind) looks like about 25 minutes. With any luck it had some run on it before you detected it but if not you only have to dodge and the last few minutes and then the weapon is out of fuel.

You are now at flank and screaming away from a thing you cannot see. Is it active or passive? If it is active you should start seeing pings within five minutes of your going to flank turns. If not assume it is passive.  Now we can start to spoof the weapon. Remember the six minutes to impact at the start? It is around 20 min to impact now but you would rather not run for 20 min if you can avoid it. So, go ten minutes, then turn 90 degrees left or right at flank turns. The weapon should have been 5,000 yards behind you.  Now at right angles, you are moving rapidly out of its acquisition cone. Just prior to the turn...again here... JUST PRIOR TO THE TURN.....fire a spread of CMs.. That means a passive decoy and an active jammer.  Passive weapons hate jammers. They will mask your turn and for a few moments make more noise than you are. By the time the weapon drives past this, you can be out of the cone, with any luck. Now, assume no luck (always a safe assumption here, remember you cannot see it). Go another 5 minutes straight at flank and then turn 90 degrees again in the same direction as your first turn if you can...firing CMs before the turn. If the weapon stayed with you it is about 3,000 yards behind you now. Now comes decision time. You can continue to zig at speed for the full 25 minute run of the weapon, or you can now drop to 20 knots and listen for it. As you drop in speed if it is that close you will hear it well before 20 knots. At 20 knots the rate of closure now much higer. If it was the 2,500 worst case yards behind you then it will eat you in just over 2 minutes.  If you hear it (a bad day at Red Rock) then turn away from it at once  firing CMs.. At 20 knots or so you can turn inside the turn radius of an incoming weaspon. After the turn go back to flank turns.  Properly timed by the time the weapon can turn to reacquire you, you have opened to 3,000 - 4,000 yards and you can now simply run it to exhaustion.
XI.  TERRAIN AND COVER

In combat, it can be handy at times to be able to hide behind a bush or duck under a rock. There are not too many bushes at sea and rocks tend to get the hull dented. However, there is still plenty of good masking terrain available if you know how to look for it. First, remember that underwater you see with sound. Just as a bright light can blind a person‘s eyes, so a loud sound can deafen a person‘s ears. If you can find something noisy to hide under you have effectively vanished. A nice merchant for example sounds like pebbles tossed onto a trash can lid.  If you have one close by and can scoot under it the merchant‘s sound trace will merge with yours and from an outside viewpoint you do not exist. This is a two edged sword since that same noise will make your sonar useless. However, one nasty trick here is that while you hide another team member in the clear and silent can Enigma to you targets for you to fire at.  Since the bad guys cannot see you or hear your weapon fire (merchants are very noisy)  the boat under the merch is safe. If they do counterfire the will try to avoid the area of the merchant to avoid wasting a shot.  Really clever drivers will not put a ceiling on their weapon since the enemy can surface and then be safe.  Instead they will fire to avoid the merchant of enable past the merch. This leaves you under the merchant safe and sound.  Finally if they fire figuring you are under the merchant, stay near the keel and wait a bit. Merchants are a lot bigger than you are and torpedos  like the big ones (delusions of Carriers dance in their tiny heads) so you wait until the pings are nice and loud, then slip out the back way.  Passive torpedos like merchants even more with their big noisy engines.

There is a way out here if this trick is being played on you. Fire two weapons about 60 seconds apart. Their traces will merge and look like one incoming. The first nails the merchant  (Big boom). The bad, evil, and wicked  enemy sub slinks away while its commander is giggling an oily giggle of victory and then the second weapon, unhead because of the Big boom, suddenly shows up enabled past the dead merchant and in the bad, evil wicked sub’s shaft seal. This sort of tactic is rough on the merchants but that is what they have Lloyd‘s of London  for.

No merchants close by?  Then use other masking sounds. Biologics can work if you can find them. Whales going in the direction you need to go are more than happy to have you with them and they will mask your ship sound as they chat with one another (“Hey mom....look at that big sucker!“ “Hush Moby, and pretend not to notice.“)  Stationary biologics such as shrimp beds can provide limited coverage also. This is like attacking a target with the sun at your back. Set up, so the biologic is behind you and on the bearing line to the target.  This is not a great mask, but better than nothing is.

Finally, you can make a mask with a team. Line up your boats on a bearing you want to move on and have the last boat in line 5,000 behind the next boat in. Let that boat make noise. Cavitate, sharp course changes left and right...etc. This will make a big noise trace and attract incoming. If the bad guys shoot right, they will enable their weapons after the pass the rest of the attack group. Now the bad guys are facing their empty tubes towards the attack group.  Mr./Miss. Noisemask now bugs out and evades. This will expose the attack group close in but again, bad guys have empty tubes and are about to feel a serious “tremor in the force.“ This trick does not work against a disciplined  team of sub drivers. They know better and will use a designated shooter to take out the noisemaker. However many sub teams are formed ad hoc and are anything but disciplined and it is very common for every boat in the group to fire.  Use this tactic only if you feel the other team is ragtime in their operations. If the other team knows what they are doing this tactic can get you killed.

Now then, use of terrain. One trick helicopter pilots like is a “pop up“ maneuver. They can sit behind a hill, blocked off from enemy fire and while a spotter out ahead calls the target. The helicopters  increase altitude to get higher than the hill (the “pop up“) and fire at the target. Then they get behind the hill again. This works with boats and Seamounts (underwater mountains). Get one between you and the bad guy and (s)he will not see you. Further, if (s)he fires active at you if you are close to the base of the mount its sonar shadow will cover you and you will not be acquired. Finally, if the bad guy goes active that same sonar shadow will protect you from that. You are invisible. You can fire “over the shoulder“ and steer the weapon out from around the Seamount at the bad guy.  Counter fire will not even be on your bearing.  Yes, Seamounts are our friend.

The down side here is a passive incoming might snap you up. Active pings will curve as they leave the weapon‘s transducers according to temperature and salinity of the water. If you are in the sonar shadow of a Seamount they curve past you. However your noise also can curve and it is possible that even hidden a passive can detect this. It is unusual, but not impossible. Finally if the evil, nasty and wicked bad guys figure out you are hiding there they can curve an active torpedo behind the mount. You will not hear it approach (The shadow knows, but you are clueless) and if they enable it right the first you will hear of it if the two or three pings before it kills you.  Bad guys got no social graces...

Use of layers has been talked to death. Use them. Layers are our friend. Scuttling up and down between them confuses bad guys and torpedoes. Change layers every few minutes and listen. If you are feeling fiendish you can layer search both at once. Put you boat at two feet above layer. Your towed array always sags behind you. At 5  knots, the sag is enough to put the towed array below layer, while your bow array is above layer.  Effectively you are searching both layers at the same time. Resting on the bottom gives limited protection. Passives will have a lot of trouble acquiring you but actives could care less. Their sonar can still pick you up, not well, but well enough for a hit. If this happens evade but stay close to the bottom. Torpedoes picking up bottom return as well as you confuse very easily. A single sharp turn out of the cone is generally enough to do the job.

 

 

XII.  MINE WARFARE

 

A mine is a terrible thing to waste. You might as well get some mileage out of them. All ships have swim out mines. The SLMM is a modified Mk37 weapon. Despite the loud noise on launch, that is all show. It is a swim out weapon and launches silently. It has a range of approximately 40,000 yards and a speed of 12 knots.  It is pre-set up to proceed to a designated location and then activate. Upon activation it has an influence field with a radius of 1,000 yards. Anything that enters that field can set off the weapon. This 1,000 yard field is why the simulation will not let you set the mines any closer than 1 minute of lat/long apart. One minute is one nautical mile or 2,000 yards. With fields at 1,000 yards two mines side by side are just out of each other’s influence range and form a barrier between them that when crossed will make one or the other explode.

 

Mines have a depth limit of 500 feet. Below this the water pressure will crush the mine’s activation mechanism. Water has to be shallower than this for effective mining and below 400 is even better.

 

Strategically mines are best used for choke point interdiction.  If you set up a minefield at the throat of a waterway, nothing will come through unscathed. Ships or torpedoes will explode. Tactically mines can be used for all sorts of nasty little surprises both offensively and defensively (see “Blue Defense”).  As an offense weapon a mine makes an excellent minesweeper. If you suspect a choke point is mined and do not want to waste a torpedo to find out or risk your ship, send a mine through. If it is clear then it is safe for you. If it goes boom then you blew a hole in the minefield you can go through…and confused the bad guy. The enemy did not hear your mine (they are silent) or your ship…or a torpedo. From the enemy perspective, his/her mine just went boom for no reason. It is always a good idea to have the bad guy confused and wondering. It keeps them from getting bored.

 

A sneaky use of a minefield field also is to lay a line of mines along an enemy evasion path…then drive well away from it and shoot at the bad guy.  The bad guy counter fires and evades and in running trips the mines. This works best with team dives…where one diver mines and the other shoots.

 

Mines also make a good defense if you are in a pocket. Sometimes you have nowhere to move away to due to landmasses and enemy ships. In this case you can lay a minefield between you and the bad guys. Take care to leave a shooting hole so you can fire. Now you can shoot through your own field and have a very good defense against incoming counter fire.


Suppose the water is deep….mines are of no use you think. Well they do have uses, but different ones. A mine in the water makes an excellent active sonar reflector. If you get pinged with mines out….all the returns will tend to hide you.  Mines can make excellent noisemakers. Send out a mine and send out a second mine to overrun the first after it has activated. The mines will go bang. When they do you have a good three minutes of invisibility to do things in…like shoot undetected close to the enemy and by the time sonar clears your weapon is right on top of the bad guy. Using mines in this fashion also confuses the enemy. Explosions with no torpedoes detected…..explosions from areas no ship is in (set the mines to go boom a long ways from you…and he will think you might have shot yourself or done something silly. He will shoot in that direction.). All this will tend to make the enemy nervous as he or she does not know what is going on and a nervous sub driver makes mistakes.  This is an element of psychological warfare you can use that costs nothing except four mines of dubious value in deep water

 

 

XIII.  SHIP ASPECT and CONTROL

 

A 688 is 312 feet long. If you are going down at 30+ knots trying to reach the bottom to skim it you will be diving at a 25 degree dive angle or more. The fathometer of a 688 and Sea Wolf is located amidships. That means that 156 feet of ship is sticking out ahead of it. In a 25 degree down angle, this means the bow of the ship is (sin25 * 156) = 65.9 feet BELOW the fathometer. A lot of divers have been startled to auger into the bottom at 30+ knots when the bottom was 1550 feet and they were going to 1500. The ship does not handle like a jet fighter and as the angle comes off, the bow goes below the set depth and then comes back to it. In this case, you can bottom hard at 1550 since the bow was at 1566 when the amidships portion was at 1500.  To get around this, issue small depth changes sequentially. The down angle is much smaller for a 100-foot depth change than a 1,500-foot depth change.  For the above example, crash down hard to 1400 feet, then sneak down the rest of the way 50 feet at a time and you will do fine.  WARNING – you have a stern. An extreme up angle with the bottom at 1550 feet will slam the screw into the bottom and also sink you. Going from 1500 feet to 100 feet at 30+ knots will have the planesman put you in an extreme up angle almost at once which can cause this. Always be aware of ship angle when running close to the bottom.

 

Ship aspect is simply what the bad guy would see if he or she were to look at your ship with super x-ray eyes from a distant.  This becomes important in active sonar evasion as well as passive sonar detection. The “spinny” end of the ship is the noisemaker.  If your screw is within the enemy’s imaginary “field of view” he or she can detect you a lot easier than if the bow is pointing at that same enemy.  For active sonar, a broadside view of the ship gives back a huge trace where as a bow or stern view gives back a tiny trace.  Bow on, a ship trace can easily be mistaken for a torpedo or missed altogether. If your WLR detector tells you that you have just been pinged, find the ping bearing and compare your ship’s heading to it. If it was broadside to you, it is a good bet you have just been detected. It is a good idea to get out there before enemy torpedoes find you.

 

Ship turns are always given as ten degree rudder orders. To change that, you can manually grab the rudder indication and turn at whatever rate you wish.  This works well at slow speeds also. During the first five minutes to weapons free you might want to establish a certain angle relative to an enemy contact. At two or three knots this is very slow with a ten degree rudder and you might not complete the turn before weapons fly. A manual rudder order can help get you on the course you wish to be before you become a target.

 

The ship can generate much more noise than normal if you are at a speed to cause cavitation. Cavitation occurs when the speed of the ship’s screw (that is the spinny part) is so rapid for a given depth that the ship is at, that the natural pressure drop as the water moves over the blades of the screw causes gases to come out of solution forming gas bubbles. The bubbles then collapse when they are clear of the screw causing a significant level of noise. Also, the screw adds energy to the water about it. Sufficient energy for a given pressure will cause steam bubbles to form exactly as you get in a tea kettle (little known fact of physics. Cavitation bubble temperature have been actually been measured with interior temperatures in the thousands of degrees, in a bubble only a few microns across.) . The bottom line of this is that it makes your ship noisy. Noisy means detected and detected means dead.  To stop cavitating you must reduce your speed or increase your depth. At 540 feet or below, you may in general run at any speed without cavitation.


XIV.  STRATEGIC COMBAT CONSIDERATIONS

 

When you engage enemy forces, the engagement is generally three distinct phases.  The first phase is to identify and localize the enemy.  This phase is basically a sensor duel: the boat with the best sensors and the best position to use them generally wins.  Victory, in case you wondered, is definitely identifying the target as hostile, and acquiring sufficient accuracy to fire.  Aggressive captains who don’t mind wasting weapons sometimes fire with 50-60% solutions, but a patient captain will wait until they have at least a 75% solution, preferably 99%.

 

This first phase of the combat very often determines the results of the latter phases. It is difficult because you are attempting to locate a boat with the same sensor capability as your self, while remaining undetected yourself.  Earlier in this manual various techniques are spoken of in cross layer searches, ping steal techniques and so on. Sections have talked about using terrain for cover or using geography. Noise propagation and ship aspect and on and on. A large series of tools have been give to you. Now, we integrate that information.

 

You enter a combat. The first thing to do is stop the engine. You have no tactical information at this point and no situational awareness of the combat. You are completely vulnerable. Stop the engine, stream your towed array and make your ship ready for combat. This can all be done in the first 60 seconds.

 

Now, when this is done you are ready for combat. There are two kinds of submarine drivers in combat, hunters and trappers.  Either technique can be used depending on the circumstances of the dive. We will discuss the hunt. At this point you are at all stop. Search for contacts and classify all that you have.  Unless it is a knife fight, chances are you will have no enemy submarine contacts at this point.

 

Now put on a slight degree of speed, say three knots or so, and change layers. This may take some time. If it does take this time then let it. You get no extra points for speed in kills.  Once you cross layer, look for more contacts. If you have none, start a standard turn 90 degrees from your base course maintaining the slow speed. Then cross layers again, search and turn another 90 degrees. A good initial scenario entry search takes about ten to fifteen minutes. You are looking for anything close and silent looking to kill you.  If you get a TIW report at T+5 (standard weapons free time) then you have a bearing (from the report) and a range (since you remember that a firing ram is picked up about 12,000 yards away).

 

If you got all this then you are lucky and most likely diving against a less experienced diver.  Old hands know that giving a TIW report out is the kiss of death since their bearing and range is compromised.  Less experienced divers like to get weapons out at once in an attempt to sink something.  Keep in mind, they may have another contact (not you) they are firing at and have to fire at t+5 or be destroyed themselves.

 

Back to the hunt, suppose you got so far from your searches, nothing. You have searched slowly on both layer sides, and have nothing.  That means that most likely there is no bad guy close to you.  So far you have not truly been hunting, but making sure you were not being hunted. Now we take a serious look at the map. Is there geography? Deep or shallow? If shallow, what is the topography of the bottom like?  Could a bad guy be sitting on the bottom waiting for you (a trapper, not a hunter)?  If so, what would be a good location for that?

 

You could ask dozens of questions. Let’s assume you have not got any good answers. The hunt begins. A good idea is to go to periscope depth and raise the ESM. Anything emitting out there you will find. You might get lucky and find a 688 radar signature from the bad guy who is up there emitting away. However, normally you just find surface traffic. Mark it and plot it. Right now you are developing the situational awareness you will need for victory.  After your surface ESM check, now go deep. Go as deep as you can and at no more than 5 knots. Monitor sonar closely. You are searching for a convergence zone (CZ) now.  They can be sudden and small (like between 485 and 495 feet you get a sniff that vanishes). If this happens write down the depth and order back to it. If not, monitor all the way down, then head back up doing the same.


No luck again?  Okay, then its time to travel. Pick a bearing more or less in the opposite direction of the bearing you entered the scenario on. Check your layer pattern. If it is surface duct, go below layer. If a bottom duct, go above layer (check out whiz bang sonar picture earlier in this manual).  Now you have your depth, put on 10 to 15 knots and move. Set up a sprint distance by time (15 knots, six minutes = 3,000 yards) and then use your stopwatch to cover the distance.  It is a good idea not to do the same speed for more than six minutes.  The 688(I) TMA updates every two minutes and three dots, and you are made. Varying speed will confuse the TMA assistant, assuming you are being tracked. Old divers always assume they are being tracked.

 

After going the predetermined distance you selected, slowly circle and search. Change layers are necessary and repeat. Look for CZ contacts. If the search is negative, then repeat the travel process again, then the search again.  Search until you make contact and can begin the attack phase.

 

A couple of helpful items for search if you need them. Know who you are diving against, and gauge your tactics accordingly. New bad guy divers are often impatient. After a half an hour of no contact, they ping, or scream off at high speed, or do something else perhaps not ideal for the situation.  If they do, you have them.  Old bad guy divers will wait till hell freezes over before doing something foolish like that. They have learned patience.  For someone like that a scare fish can help. Fire a 35 knot, active fish real deep (and quiet) away from the combat area using OTS shooting. Then over the next 15 minutes, steer it away, then parallel to your search line of advance. Every couple of minutes, enable it. This will help to flush out any bottom dwellers (and you will them scoot off on sonar) and will also tend to draw fire towards the weapon.  Either of these things you the hunter are looking for.  If you see it, the hunt phase is over. You have a target.

 

Now, you did all this and nothing. This likely means you are up against a very experienced bad guy.  You cannot find him (or her, bad guys are gender indifferent for a title).  There comes a point, where you now have to take a calculated gamble.  Go slow and just above (or below) layer and go active sonar (ping).  Track all contacts. Change layers and ping again.  From your situational awareness you determined earlier, you know where all the good guys are. You also know you will pick up surface traffic on an above layer ping, and likely not on a below layer ping.  Sort out your contacts, and determine which green dot might be bad guy.

 

Now if the bad guy is in fact experienced,  (s)he is now also worried. Active paints the bad guy boat, and (s)he must assume that there are only seconds to react in before being shot at. If they shoot at you, great. Now you have a confirmed bearing to that green dot you wondered about and have an exact position. A finger (see tactics) on it will work wonders.  If they do not shoot at you….well…bad guys got no couth as is well known. Now you have to guess a bit more.

 

Once detection and a firing solution are obtained the attack phase begins. The boat that launches the first well-planned attack is often the victor.  A well-planned attack keeps the target unaware of the attack until the last possible moment, with no chance of countermeasures or escape.  Ideally, the attacker does not reveal his position during the attack.  The best attack is therefore quick, quiet and decisive.  Sadly though, shooting is noisy and often as not your fire gives away your location. Try and shoot across layer to help silence your fish.  OTS shooting is a major factor here for not giving away your location.  If you can, dogleg the shot away from you first, then towards the enemy.  That way counter fire will not be a threat. If you have the bad guy, then the bad guy very possibly has you. The attack phase must be rapid to get fish out before your opponent does.

 

Once the attack is delivered, the escape phase begins.  If you alerted the target or if other enemy units are in the area, you can expect to find yourself the target of their counterattacks.  Now self-preservation becomes an overriding consideration.

Immediately commence to exit firing datum in a controlled fashion immediately after firing weapons. Seventeen knots is a good speed, and choose a course at right angles to the firing bearing of the weapons.  If you detect counter fire, track it. Is it at you, or on the bearing your weapons came from (now we see why we move at right angles to the firing bearing).  Get some feel for the course of the incoming. You can do this in seconds by eyeballing the trace (see LOS section).  Try to set an opening course to the incoming to stay out of its acquisition cone.  If you have no other choice, then light the fires high and get out of Dodge City at flank. Use HFS spins and weapons evasion as needed to remain alive.

XV.  GENERAL COMBAT TACTICS and TECHNIQUES

 

a.  Wild Fish Riding

 

Let's assume you were in a combat with multiple divers. During the melee you had to open the engagement area.  Now you were keeping track and the one diver left is some 25-30 nm away from you. How do you close that distance for the kill undetected and still get in there in a reasonable time? One method is wild fish riding.

 

Set up a single fish for the general direction you want to go. Run it shallow, say 200 feet since this will increase its range and make it noisier. Set the speed for 35 knots and set a floor on it of 500 feet. Set enable for 10,000, but after firing pre-enable the fish to defeat the 10,000 yard enable. After all that...shoot it.

 

Now set your ship depth for 600 feet and follow the fish at 35 knots. Turn on your HF to locate the fish and keep it screen centered. Prepare your remaining three tubes for combat and make miles.

 

Now the other side of the combat is the bad guy. The bad guy is running nice and quiet and knows the good guy is a ways off. He may do "sprint and drifts to close". This is fairly routine. Suddenly he gets a report of "Torpedo in the water". “Holy underwear!”  (s)he exclaims and goes to sonar and gee whiz, there is a trace. Now the bad guy knows the good guy is a long ways off and so will probably think that this is a slow run fish out to search a zone. Chances are (s)he will change course so the fish will miss and not bother to waste a torpedo since the good guy will be long gone from that firing bearing before the fish can find him. The bad guy will put the sonar display cursor on the sonar trace and hear that torpedo scream. The enemy might even try a single ping active and get a return from the bearing of the torpedo. If the enemy is an experienced sub diver  (s)he will open the incoming torpedo course slowly while monitoring since there is no sense in a speed run that can give away position.

 

Now you, the good guy.  You are riding maybe 100 yards behind that fish and 53 minutes after firing it enables. Now go to all stop. The fish may or may not acquire you but since you are below its floor you are safe.  It will ping and pong a few minutes if active or S-curve around if passive...and then go dead. The bad guy will hear all this....and grin his or her oily smile thinking how you just wasted a fish. What the bad guy will not think is that you got a 25-mile free ride undetected into his zone. (S)He saw the fish but not you. Now be "werrryyy werrryyy quiet…..we’re hunting wabbit"...and listen. Chances are very good the bad guy will do a sprint to close to where (s)he thinks you were. Now you have good TMA and can fire a kill fish. A bad guy in a sprint is running blind. He or she learns about the incoming when it smacks into the side of the hull. “Hi Mom, I’m home.” and its all over.

 

This is a risky maneuver but it can get you to the target in a half an hour.  After that you have the element of stealth and surprise for the kill. A variant is that at any time, you can go to all stop and vanish while the torpedo screams onward.

 

b.  Tomahawk Sonar Targets

 

Tomahawk sonar targets or Tom returns. One boat targets Toms in a pattern around a suspected enemy position and fires. The Toms enter the water and for about 15 minutes and give the bad guy all sorts of bogus sonar returns. With all that scrap iron present a shooter can sneak in fairly close for the kill. If you try this one the shooter MUST use passives for the kill shot. An active will very happily ping its little heart into a dead Tom and blow it perdition. The down side of this tactic is firing Toms makes a LOT of noise and if a bad guy is listening you just told him where you are.

 

c.   –Deleted-

d.  The Glacier Five Minute Fake Out

 

This is very useful when combat becomes up close and personal.  Assume you start a game and have some solid sonar contacts on bad guys. The chances are excellent they have you also.  They will want to get that first shot off fast and accurate and hopefully take you out in the first few minutes. Bad guys got no couth. A useful technique to defeat their evil and nefarious intentions is the Glacier Five Minute Fake Out. To do this before ROE weapons free crank up a bell. Let the bad guy see you. Crank up to flank and give him good TMA showing you trying to run off the planet before weapons free. The bad guy will track and fire at weapons free cackling an evil laugh at the easy kill (s)he assumes is about to happen.

 

Now you the good guy fire at the bad guy and turn 180 degrees from your original base course. Your weapons fire and the bad guy weapon fire will completely mask your turn. Enemy TMA has you at flank screaming off somewhere and will now be completely wrong.  In fact after the 180 zig it is very possible you can go to all stop in perfect safety…and simply listen now.  To the bad guy you vanished in torpedo sonar return noise and it is very likely (s)he is now cranking some speed to avoid your fish.  Now you can simply sit and watch sonar and guide your fish to the target.  You have complete tactical advantage and total stealth and the bad guy is in serious trouble.

 

e.  The Hollywood Charge

 

This tactic is named after Commander Hollywood who uses it whenever possible. It is a frightening tactic and can be deadly. In it you once more start an engagement up close and personal. Assume you have a target 3,000 yards away. You have the target and the target most certainly has you. In the Hollywood Charge you set your weapons for minimum enable…and drive your sub at the target at high speed. The bad guy target sees this on sonar and it scares him witless. (S)He turns and runs. Now the bad guy is toast. You, charging the bad guy have a nice HF target and the bad guy is blind. At weapons free you simply fire at the HF target and come off the bell to open distance so your own weapons do not kill you.

 

The counter for this is simple but does take a degree of nerve. Set a ceiling on your weapons of say 100 feet and go to PD.  Now hold position and let the bad guy charge.  When the bad guy is committed, charge back shallow. The bad guy passes under you and you suddenly vanish from his/her HF. The bad guy is likely charging deep to lessen sound. You are shallow and making all sorts of noise. However  (s)he cannot hear you since he is at flank. Now set your weapon course for 180 degrees from your base course and fire at weapons free with minimum enable. The torpedoes will go out and go crazy. They might acquire you but the ceiling protects you. They will acquire the bad guy and take him/her out.

 

f.   Silent Evasion

 

This only works with passives and a strong, shallow layer present. It also requires nerves of absolute steel. If there is a layer less than 200 feet the chances are very good a passive coming at you is set to enable at 200 feet or deeper. Since the default enable depth is 200 feet in Sub Command the vast majority of all shots use that. Now to evade that incoming passive go above layer and then go to all stop.  Do not even allow 1 knot of speed.

 

The layer will shield your normal ship noise (compressors, fans, reactor coolant pumps…etc. You are never completely silent) and with no screw noise the passive will never see you. It will zip on merrily by. An added advantage to this is that you have vanished from enemy sonar as well.  The bad guys will think you cannot possibly be where you are since they shot on that bearing and the torpedo did not even sniff you. The tactical advantage and initiative is now yours.

 

A second variant on this is to bottom your sub (very carefully). This does not work as well since there is no protective layer to shield your plant noise and a close passive will snap you up. In this state you have no defense and no chance. If the layer is a deep one, say 400 feet or so, you might consider bottoming for passive evasion. Be very gentle in this evolution for smacking the bottom at to much speed or angle is as fatal as eating that torpedo coming at you.

g.  Hammer Shot

 

A Hammer Shot (HS) gives the bad guy nowhere to run, nowhere to hide. It takes timing and close attention to set up but once in place is a deadly as a Tholian Web (hats off to the Star Trek fans).  The best way to explain it is by example.

 

Assume you have a target bearing 000 or suspect the enemy is at 000 and you want to set up a Hammer shot. Set two weapons on ACTIVE and set speed for 35 knots and run em deep. Fire them on 090 and 270 at weapons free while facing on course 180 (over the shoulder shooting, see the section on Fleet tactics). Now time the shots and slowly (like 1 knot) come around to course 000.  You want those fish you fired at least 10,000 yards away from you, which at 35 knots will take nine (9) minutes.  There is an excellent chance the bad guy never heard the shot and does not hear the fish yet. Now….after nine minutes steer both fish to course 000. You are on course 000 also by now. Let the fish run and come up to 5 knots or so. Prepare your remaining fish for regular shooting on course 000….and listen.

 

The bad guy is listening and waiting when suddenly he hears ‘Torpedo in the water bearing 250”….a moment later (s)he may hear “Torpedo in the water bearing 100.”  Now…the bad guy has one east …and one west. The bad guy very likely will NOT fire on 180,which is where you are.  (S)He will track a bit and might fire one east and one west. If (s)he tracks,  (s)he will see your incoming fish headed north and not be bothered too much by it.

 

Now we come to hammer time. When the fish are PAST the range of the target, swing the west fish to 090 and the east fish to 270 and enable them.  At the same time fire your direct fish at the target. Now the bad guy has an active banging away from the Northeast and one from the Northwest. (S)He will crank up a bell to get out of Dodge and will never hear your direct fire fish. Where will (s)he go?? The only open path for safe evasion would be 180 which is where your fresh fish (s)he never heard are waiting for a target. You will drive the enemy right into those shots and then the Hammer falls. If (s)he detects your incoming from 180 on HF and tries to evade there is a very good chance the NE or NW actives will make the kill. I once saw this tactic result in four torpedoes hitting the same target within a few seconds if each other.

 

This tactic takes a great deal of patience, skill and some luck. However when employed correctly it is terribly effective.

 

h. -deleted-

 

i.  Finger Fire

 

Suppose you are in a combat where you know you are overmatched? The bad guys are old and jaded and you know they have all the little tricks up their sleeves. What can you do? One tactic that works well, especially in a team dive is a FINGER FIRE.

 

Here is how it works. Assume you have a rough direction of the bad guys but no real idea and no decent range. You can guess since it's early in the game (use this early in the game) they are at least 20,000 yards away.  Point your ship on the bearing you want to set up the finger on for firing. Lets say in this example you want to fire east on 090. Turn your ship to 090 and adjust your depth till you are on the layer. Set your torpedoes for PASSIVE, 35 knots, 10,000 enable, enable depth at the layer or as close to it as you can. Now set the course so tubes 1 and 2 are going to fire at right angles to your ship (course 180 in this case) and set tubes 3 and 4 to fire at the opposite angle (course 000).  Now get a stopwatch and fire starting the watch at the time of fire.  At PRECISELY 1 minute and 42 seconds, turn weapons 1 and 3 to course 090. At PRECISELY 5 minutes and 8 seconds, turn weapons 2 and 4 to course 090. What you have now done is set up 4 weapons with 4,000 yards horizontal separation moving east. Now look at your right hand held flat. Note the fingers. The weapon geometry is exactly like your fingers. The center ones a bit further out than the outer ones and all pointed the same way. This is a Finger Fire. The weapon ranges were set so that the detection cones overlap at the edges. The entire frontage of the weapons is 16,000 yards. Anything inside that 16,000 yard band will get snapped up. Anything in that band that tries to evade one weapon is very likely going to get picked up by another to the side of it.  If you have a partner who can work with you and tell time you can set up two fingers side by side, for a 32,000 yard frontage.  Once you have fired and set up your weapons evade at right angles to the firing base line course (in this case evade on 000 or 180).  If with a partner, have him or her evade in the opposite direction you are going and use about 16 knots to get out of there. That is just fast enough to move you and still maintain sonar.

 

Using a Finger, is the shotgun approach to weapon employment. You do not have a target but are looking for one. You are now evading and your weapons are slowly making their way out.  Now comes judgment. If you think they are on the close side leave the finger alone. If you think they are far then pre-enable and wait to enable the finger until is in position (rounding an island for example).  If you are looking to scare the snot out of the bad guys have one team member use passives for the finger and the other use actives.  Evading the banging actives can drive the target into the passives.

 

This tactic is wasteful of weapons and can be dangerous as your tubes are empty now if a 688 and half empty if an Akula or Sea Wolf.  If the bad guy is a good hunter and you are not giving him the finger will keep him busy while you reposition and listen.  With a bit of luck you will pick him up maneuvering to avoid the finger and can steer your fish accordingly.  With a bit more luck the finger will enable and take him out for you.  Either way you retain the tactical advantage. This is a bit like using a sledgehammer to smash an egg but if you want the egg smashed and that is the tool you have, then you use it.

 

VARIATIONS:

 

1. Fire 4 weapons at right angles to the base fire course (000 in this example works well) at 35 knots and let them run for 12 minutes (putting them 14,000 yards from you). Then turn one weapon on course 090 every 3 minutes, 25 seconds (this puts them 4,000 yards apart). Now just sit quietly. You are clear of the counter fire zone by 14,000 yards. This will set up a sort of wedge shaped finger pattern

 

2. Fire weapons at right angles to the base course at 3 minute, 25 second intervals.  (this puts them 4,000 yards apart). At some time of your choosing turn them all to base course. This sets up a flat frontage for the search pattern. The handy thing here is you can start at once while tubes 3 and 4 are reloading from harps in the tubes. By the time you need them it will be time to fire them.

 

3. Set tubes 1 and 3 as actives, 2 and 4 as passives. Actives scare folks and while they run from them the quiet passive can snap them up.

j.  The Bulldog Slam

 

The Bulldog slam is named after Fleet Admiral Bulldog and is an attack variant using the classic active/passive combination. In it a passive is fired first at slow speed, 34-45 knots. After some six minutes an active is fired on the same bearing line also at the same speed as the passive. Now you let time go past until they reach the target area.

 

The bad guy sees a torpedo trace and it should be fairly faint since it is a slow fish (shoot this across layer if you can). Since (s)he hears nothing (s)he will assume a passive or pre-enabled fish and slowly slink away. Now comes the trick to it. Enable the passive and the active. The bad guy hears pings looks to the passive intercept and sees the bearing, then looks to his sonar and sees a trace on that bearing. The pings are likely faint (remember you staggered the firing times) so the bad guy will not panic but will move to get out of that active’s cone while there is time.

 

The trace the bad guy saw was the trace of the passive now sniffing for him. On the same bearing as the active pings (s)he has no real way of knowing it is not the active. The bad guy will set a nice and clean opening course without radical evasion or CMs and the passive will acquire and kill. This often happens with the bad guy never even knowing there was a weapon there.

 

k.  Deep Run Fish

 

This was a tactic developed by the Marauders Fleet in the Second Sea Wolves/Marauders War. It came as a nasty and costly surprise. Torpedoes can dive very deep.  Under certain conditions this can be very useful. In deep water with no or a very small layer set the fish to run at maximum depth enable depth and shoot from your ships maximum depth. Fire the weapon PASSIVE. What will happen is that on enable the fish will dive and search. This makes it almost invisible to the target ship. A deep fish is nearly silent and only detected when it is very close.  The sonar trace looks broken and splotchy and does not sound like a normal torpedo.  It might be dismissed as a merchant or biologics. The weapon can detect a sub from its maximum search depth and when it does goes straight up to it making this an almost vertical attack from below.

 

This tactic is very dangerous but also limited. Any real layer and the fish will not see a sub above the layer. A sub at “All Stop” will not be seen. A sub moving at 5 knots or so might not be seen. The shot has to be about perfect to get the weapon into the target zone. Within these limitations though it is very effective.

 

l.  Blue Defense

 

A mine is a terrible thing to waste, so don't. Lets assume you are in shallow water (less than 300 feet) and running with an incoming on your tail.  You cannot use depth to help shake it and if you are in constricted waters your ability to maneuver is limited making the use of CMs far less effective than they otherwise are. So what can you do? Screaming along at flank will not out run a torpedo and harsh language will not impress it.

 

One thing to do is to have a SLMM loaded and ready. As you run plot a SLMM landing point ON your position. Then open the tube and shoot the thing. It will take about a minute to impulse out and turn back to where you were (remember you are moving at flank and have moved since the plot point was locked in) and then land.  In a minute you are 1,333 yards away form it when it activates. You want to be at least 1,000 yards away or its influence field will detect you. Now the torpedo screaming at you went some 1,833 yards in that minute and is close to the SLMM.  As the torpedo screams over it the SLMM will detonate and destroy the weapon. An added bonus is that if the incoming is active there is a fair chance it will lock onto the mine as its primary target.

 

When out of CMs or in constrained waters a mine can be the difference between an escape and being scrap iron. This has been used in actual combat, and it works well.

XVI.  MISCELLANEOUS DATA SHEET

 

ALL

Depth weapon settings are accurate. Note, ship depth is keel depth. Beware surprises.

Weapons can acquire a whale.

 

Sea Wolf Data

 

Detect 688(I) at 5 knots

Detect SW at 5 knots

 

Cross  layer –        28,000 yards BQQ-5, TA

                                28,000 yards BQQ-5, Demon

 

Maximum detection range about 40,000 yards on all classes of sub target.

 

Broach Depth: 60 feet

Radar Depth: 62 feet           

Periscope / ESM Depth: 70 feet

Snorkel Depth: 70 feet

 

Radar – Unable to detect a snorkel or mast.

 

 

Akula

 

24,000 yards detects another Akula, parallel course, 5 knots

 

Active sonar is not possible above 18 knots.

 

Active good acquisition at 24,000 yards

 

Broach Depth: 13 meters

Radar Depth: 14 meters

 

 

688(I)

 

Radar Mast – 55 foot limit – 3 knots top speed

ESM Mast – 60 foot limit – 10 knots top speed.

Radio Mast – 60 foot limit – 10 knots top speed.

Periscope  – 60 foot limit – 10 knots top speed.

 

Broach Depth: 50 Feet

Test Depth: 1600 Feet