Silent Service
NES-IV-USAUltra(r) GamesHow to play Silent Service(tm)---Find 'em, chase 'em, sink 'em!Just above the beat of your heart, you hear hostile propellors churningthrough calm seas. At any second the first depth charge will explode. Yourwatch ticks. Sweat rolls into your eyes. As the enemy's sonar ping intensifiesyou hold your breath, realizing that the pressure of an unmerciful sea is allaround you.Such is your life as a commander in the elite Silent Service Force, a detailedsimulation of World War II submarine missions in the bloody South Pacific.From the moment you dive into action, you'll be confronted with the sameinformation, problems and resources available to an actual sub captain. Yourprimary mission will be to take on the Japanese Navy in their home waters andto neutralize the Japanese Merchant Merine.With a limited number of torpedoes and fuel, your goal is to sink a maximumtonnage of enemy ships and bring your sub safely back to base. Your overallevaluation from Fleet Command will be based on the number and types of shipsyou sink.So go get 'em commander. Your crew is counting on you... because they know ifyou fail, they'll become instant shark bait!US Attack SubThe US Fleet Submarine of the Second World War was an outstanding weapon. With200 tons of diesel fuel and a cruising range of 12,000 miles, no area of thePacific was safe for enemy shipping.---Mission optionsThere are three types of scenarios. "Torpedo/Gun Practice" places you outsidethe America base at Midway Island. Four old cargo ships are anchored there astorpedo and gunnery practice targets. "Convoy Actions" recreate a variety ofactual submarine attacks on a convoy. "War Patrols" allow you to command anentire patrol, putting out to sea from submarine bases at Midway, Brisbane orFremantle, continuing through a number of convoy actions, and concluding witha victorious return. (Or sunken dreams!)To select your mission option, press the Control Pad Up or Down and lock inyour decision with the A Button.Skill levelsThere are four skill levels: MIDSHIPMAN (beginner), LIEUTENANT, COMMANDER(designed to be the most historically correct), and CAPTAIN (expert). Theskill level effects the accuracy of torpedo runs, damage from depth chargeattacks, and the skill of enemy lookouts and sonar operators.Lock in your skill level by pressing the A Button.Combat difficulty levelsYou can customize your mission with various "combat levels." Each levelintroduces an element that's more realistic and more difficult. They include:Limited visibility. If this level is selected, enemy ships which are beyond radar/sonar range won't appear on the map displays.Convoy zig-zags. If this level is selected, enemy convoys will "zig-zag" (change course) at regular intervals. If this level is not selected, cargo ships will steam straight ahead unless they are attacked by torpedoes or encounter land masses.Dud torpedoes. Some of your torpedoes may be "lemons" if you select Dud Torpedoes instead of No Dud Torpedoes. Dud torpedoes may hit the enemy but will not explode.Port repairs only. If this level is selected (instead of Repairs Under Fire), repairs will no longer occur automatically while in battle or on patrol.Expert destroyers. IF this level is selected (instead of Standard Destroyers), certain enemy convoys will be escorted by "expert" destroyers. These escorts are more persistent and have better trained sonar operators.Convoy search. If this level is selected (instead of Close convoys), convoys will not always appear within radar range. You'll need to search them out. Far off convoys are best sighted by performing a 360 degree periscope/ binocular sweep of the horizon.To choose your levels, press the Control Pad Up or Down, then make yourselections by pressing the A Button.Overall difficultyThe skill level and difficulty levels you select combine to produce an overalldifficulty factor from 1 to 9. This difficulty and the tonnage you sink willdetermine your ranking in the "Submariner's Hall of Fame" at the conclusion ofyour mission.---TerminologyPort: the left side of the ship.Starboard: the right side of the ship.Bearing: the direction you are looking.Heading: the direction your ship is going.---Control functionsRaise or Lower Periscope: This command raises scope if it's down, and lowersit if it's up. It also sets the visual bearing to be the same as the sub'sheading. You can use the periscope, in daylight only, down to a maximum depthof 44 feet.Throttle (Speed): Choose from Dead Stop (0) to Full Speed Ahead (4).Reverse: Use to reverse engines for an emergency escape. To change speed whilein reverse, adjust the Throttle, then select Reverse again.Guidance Control: To dive, move the arrow onto the down pointer of theGuidance Control. To surface, move the arrow onto the up pointer of theGuidance Control.For left rudder, move the arrow onto the left pointer of the Guidance Control.This turns the sub toward the left (port). If looking at the Map screen, youwill see the sub turn counterclockwise.For right rudder, move the arrow onto the right pointer of the GuidanceControl. This turns the sub toward the right (starboard). If looking at theMap screen, you will see the sub turn clockwise.To cancel all dive and turn commands, move the arrow to the center of theGuidance Control and press the A Button.You can also blow emergency tanks by holding down the B Button and pressingthe A Button on the player 2 controller. This can halt an otherwise fataldive, and usually brings your sub to the surface. You may perform this onlyonce per engagement.---Time scaling definedIn order to ensure accuracy, all ship movements, sightings, torpedo runs anddive rates are recalculated every two seconds of simulated game time. However,under most conditions it is desirable to speed up the action somewhat.Normally the simulation proceeds at four times real-time: One minute of gametime takes 15 seconds. If the "F" is selected on the clock, the time scale isdoubled. Repeated pressing will continue to increase the Time Scale up to amaximum of 32 times real times (ie. one hour of game time will take 2 minutesat time scale 8).To increase the Time Scale, move the arrow to the "F" of the Time Scale andpress the A Button. Each subsequent key press doubles the speed, to a maximumof 32 times real time speed (three key presses).To return to the normal Time Scale, move the arrow to the "N" on the TimeScale and press the A Button. Note: You automatically return to normal timewhen detected by the enemy or when you fire a torpedo or the deck gun.---The conning tower menu screenThe Conning Tower screen acts as a menu screen. From this screen, you mayselect any of the four detailed battle station screens: Instruments andGauges, Maps and Charts, Periscope/Binoculars, and Damage Reports. (See below)Use the arrow to position the captain at the desired battle station, thenpress the A Button. Moving the arrow to the Map Table, for example, moves thecaptain to the table. Press the A Button and the Map screen will appear.You may also select two special functions from this screen. If you are playinga Training or Convoy Action scenario, the "End of Game" function will end yourmission. If you are playing a War Patrol scenario, the "Continue Patrol"function ends the current convoy battle and returns you to the patrollingscreen. You cannot end the battle if you are being tracked by the enemyescorts, have torpedoes active, or if an enemy ship is still sinking.The "Quartermaster's Log" option (located at the bottom right corner of thecommand compartment) is used to review your accomplishments during the currentpatrol.When you are at the Conning Tower screen, the simulation is paused. Note:some selections are unavailable under certain conditions.To choose the Conning Tower Menu, press the Select Button. Once in the ConningTower, make selections by moving the arrow to different areas (ie. theperiscope, the map, etc.) and then press the A Button.---Combat controlsThese controls are at your command when at Periscope/Binocular Battle Stations(see below). Once again, move the arrow to your selection and press the AButton.Attack controlsTo identify the target under the crosshairs on the periscope/binoculars, movethe arrow to the Target ID.To fire a torpedo at the target under the white crosshairs, move the arrowonto the Torpedo Firing Control. Bow or aft tubes will be selectedautomatically, depending on which ones face the target.To fire the four-inch deck gun at the target under the white crosshairs, movethe arrow onto the Deck Gun Firing Control. The gun may be fired only whenyour sub is on the surface.Note: Four torpedoes and gun shells (total) may be active at any one time.To increase gun deflection, press the Player 2 Control Pad UP. Each additionalpress adds 25 more yards to the deflection. You want to increase deflectionwhen the target is moving away from you. To decrease the gun deflection, pressthe Player 2 Control Pad DOWN. Each additional press subtracts 25 yards fromthe deflection. You want to decrease deflection when the target is movingtoward you. (See DECK GUN below)To rotate the periscope view left, press the Player 2 Control Pad LEFT. Torotate the periscope view right, press the Player 2 Control Pad RIGHT.(Rotating the view changes its bearing.)To release debris and oil, use the Player 2 Control Pad and hold down the AButton while you press the B Button. The debris will rise to the surface andmay convince the enemy that your sub has sunk. You may release debris onlyonce per engagement.---Battle station screensSilent Service contains multiple Battle Station screens. On each screendifferent information is available and different commands can be entered. Thebattle stations represent the main locations from which the captain managesthe battle. Not all controls are operable from all screens. Be sure to notewhat controls are available on each screen.War patrol navigation maps battle station (War Patrol scenarios only)When you select a War Patrol scenario you start out on this screen, whichdisplays a map of the South Pacific Ocean. You are free to explore any area ofthe map. Your ship is a tiny white dot near the starting port of Fremantle,Brismane or Midway. The patrol screen simulates the time required to proceedfrom your base to enemy-controlled waters, as well as the patrolling activitybetween engagements. (A typical patrol lasted up to two months.)Moving on the War Patrol map: Using the Control Pad, move the arrow in thedirection you wish to go. Time moves quickly while patrolling. The oceanchanges from light to dark to represent day and night.Finding the Enemy: When the ocean or screen border turns red, you've spotteda convoy. Press the A Button to exit from patrol if you want to engage inbattle. Note: Enemy ships are generally found along the heavily travelledconvoy routes and close to land. Valuable tanker and troop ship convoys aremore likely to be found near Japan.Getting Home: The submarine bases at Midway Island, Fremantle and Brisbane areindicated by flashing dots. When you have reached your base and the oceanturns green, you can return to port. Press the A Button to end the patrol andrecord your score in the Submariner's Hall of Fame.Important Note: No other controls function on the patrol navigation screen.To make other controls you must exit the War Patrol.---Instruments and gauges battle stations  a    d    e   f    bc          g      i  k  l   n  h   j            m   oA. Battery Level - indicares electricity remaining in the battery. Recharge by   surfacing. A fully charged battery allows one hour of high-speed maneuvering   underwater and 5 to 6 hours at slow speed. If your battery is drained,   you'll be unable to move underwater.B. Battery Charge LightC. Battery Drain LightD. Speed - Maximum surface speed is 20 knots. Maximum submerged speed is 10   knots.E. Depth - Zero means sub is on the surface. Maximum diving level is 500 feet.F. Periscope Indicator - Green means it's up, black means it's down.G. Torpedo Ready Indicator - Green means forward and aft torpedo tubes are   ready. Torpedo reloading takes 10 minutes per tube. The number under each   column indicates how many torpedoes remain in addition to those already in   the the tube. The number alongside shows the number of deck gun shells   remaining.H. Fuel Levels - Shows the amount of fuel in the three main tanks.I. Depth Under The Keel - Depth from sub to ocean's bottom. When gauge reads   zero you'll run aground.J. Water Temperature - When the dial is in the blue section, it indicates the   submarine is below a thermal gradient layer. Note: Hiding below a thermal   gradient layer can provide extra protection against the enemy's counter   attack.K. Christmas Tree - Indicates status of hull openings. Green means closed, red   means open. Hull openings close automatically when you dive.L. Compass - Indicates direction sub is heading.M. Throttle - 0-4 settings: All Stop, 1/3, 2/3, Full Speed and Flank (reverse)   Speed.N. Clock - Shows time of day. Dusk in the Pacific is from 7:00 pm (Hour 19) to   8:00 pm (Hour 20). Dawn is from 5:00 am to 6:00 am.O. Dive Bubble - Shows whether the sub is diving or surfacing. The bottom line   displays your current speed (in knots), depth (in feet) and heading (in   degrees).---Maps and charts battle stationThe maps and charts screen displays information available from the navigatorand the tracking party. Map information, visual sightings, radar and sonar arecombined on this screen to show the location of your submaring, torpedoes andall known enemy ships. Remember that your submarine is represented by a whitedot. Torpedoes and enemy ships are black dots, and green areas represent landmasses and islands.Note: Sometimes there are enemy ships out there that you have not yetdetected. These undetected ships do NOT appear on the map. Your lookoutsaren't always reliable - it's wise to leave the Maps Battle Station and lookaround the horizon with the periscope/binoculars.Zoom: You may enlarge or shrink the scale of the map to any of four levels ofdetail by moving the arrow onto the Small Scale or Large Scale Map andpressing the A Button. The initial map shows the entire South Pacific. ThePatrol Area Map shows a 500 by 300 mile area. Zoom again and you'll see theNavigation Map, which shows 60 by 40 miles. The most detailed map is theAttack Plot Map, which shows an area of 8 miles by 5 miles. Ships aredisplayed on the Attack Plot.Note: When the screen begins flashing, the enemy is either within range or youmay have wandered off the map. You'll also notice, as you patrol the seas,that the map color changes from dark to light. This represents the passing ofdays and nights.Controls Available: All Submarine and Time and Scale controls, plus "ReleaseDebris".---Periscope/binoculars battle stationThis screen displays the view through the attack periscope during daylight/dusk/dawn, and the view from the bridge's Target Bearing TransmitterBinoculars at night. The viewing area shows an enlarged image of visible shipsand land. This screen may be selected when the sub is on the surface, or atperiscope depth (44 feet or less) during daylight hours.Torpedo Data Computer: When the crosshairs turn white the Torpedo DataComputer is activated and target tracking is displayed. The TDC displays therange to the target, the target's speed, and the target's course. To fire atorpedo, fire the deck gun or request information, move the arrow onto theappropriate control and press the A Button.---Damage reports battle stationThis screen indicates the nature of any damage to the submarine. Damage maybe caused by depth charge attacks or enemy gunfire. Types of damage include:Bow/Aft Torpedo Damage: Torpedo tube doors have been damaged. The torpedoeswill not fire.Periscope Damage: The periscope housing has been damaged. The periscope cannotbe lowered or raised.Dive Plane Damage: The bow and stern dive planes have been damaged. Thesubmarine will only dive or surface at half its normal rate.Fuel Leaking: The external fuel tanks are leaking. Fuel will be consumed attwice the normal rate. In addition, fuel rising to the surface will make thesubmarine easier to detect by enemy destroyers.Engine Damage: The main diesel engines are damaged. Surface speeds are reducedby half.Machinery Damage: Internal pumps and engines are damaged. The extra noisemakes the enemy's sonar tracking easier.Battery Damage: Batteries are used up at twice the normal rate when submerged.If the "Port Repairs Only" combat level is not selected, repairs are attemptedby the crew automatically.Water Damage: If your sub is taking on water, the leakage rate is indicated ingallons per second (GPS). Leakage will often cause your sub to descend,although the dive planes may be able to counter-act the dive. This informationis provided in the top right hand side of the Damage Reports screen.---Messages and soundsYou may receive messages at any time from various members of the crew. Theywill appear on the top line of the screen. You will also hear the sounds ofyour own engines, nearby ships and torpedoes.Sonar reports destroyers closing ("ping" sound)Sonar reports depth charges dropped ("splash" sound)Depth charges exploding! (explosion sound)Lookouts report destroyers firing (gun sound)Shell hit! Sub damaged (whistling explosion sound)Bow (aft) torpedo fired! 135' track (torpedo launch, torpedo motor sound)Deck gun fired! (gun fire sound)Sonar reports distant explosions (distant explosion sound)Warning: test depth exceeded (hull creaking sound - check the Damage Reports screen!)We have run aground! (grinding sound)Repairs completed (check the Damage Reports screen)Blow emergency tank! (alarm sound)Collision! Abandon ship! (grinding sound)Completing your missionConvoy Action missions end when you select the "End of Game" option. WarPatrol missions end when you return to one of your bases. Either missioncategory ends ifyou are sunk or beached. In all cases you will see a screendisplaying all ships which you have sunk and your final rank.All players will rank at least Ensign. Higher levels are Lieutenant JG,Lieutenant, Lieutenant Commander, Commander, Captain, Vice-Admiral, Admiral,Fleet Admiral and ultimately WGSC (World's Greatest Submarine Captain)!---Convoy action scenariosConvoy action scenarios are shorter missions which place you in specifichistorical situations. They are useful for becoming acquainted with thefeatures of this simulation, practicing specific tactics or when time isshort.Plunger in the inland sea (Lt. Commander DC White)Day/SubmergedJan. 18, 1942, Latitude 33-30N, Longitude 135-00E.The USS Plunger, patrolling off the southern coast of Japan, sights anescorted cargo ship steaming east at high speed. This scenario gives you theopportunity to set up a torpedo firing solution against a moving ship.Remember that even though the Torpedo Data Computer calculates the correctlead gyro angle to hit the target, it is often a good idea to fire a spread oftorpedoes in case your targes changes course unexpectedly.Wahoo vs. Convoy (Lt. Commander "Mush" Morton)Day/SurfaceJan. 26, 1943, Latitude 2-37N, Longitude 139-42E.Off the New Guinea coast, USS Wahoo sights a small Japanese convoy. Thesituation is a submariner's dream: an unescorted convoy including a troop shipand a large oil tanker. However, the convoy has radioed for help and adestroyer is on the way! Your objective is to strike quickly and cause as muchdamage as possible. Be sure to use your aft torpedoes if your bow tubes areempty.Hammerhead at Borneo (Commander JC Martin)Night/RadarOctober 1, 1944, Latitude 6-30N, Longitude 116-11E.SJ radar picks up a large escorted convoy as the USS Hammerhead patrols thenorthern coast of Borneo. The tanker, one of Japan's dwindling handfulremaining at this stage of the war, should be your primary target. Thisscenario introduces night combat against an escorted convoy. You should takecare to avoid being spotted as long as possible. Use moderate speeds, keep aminimum profile toward the escort, and try to time your attack so that theescort is on the other side of the convoy.Searaven at Toagel Mlingui (Commander H. Cassedy)January 13, 1943, Latitude 9-12N, Longitude 130-38E.Somewhere between the Philippine Islands and the Japanese naval base at TrukLagoon, USS Searaven comes across a northbound convoy. You are in a badposition: astern of the convoy in daylight.Tautog at night (Lt. Commander Sieglaff)Radar/Visual NightMarch 16, 1944, Latitude 42-25N, Longitude 144-55E.Off the eastern coast of Japan, USS Tautog encounters a Japanese convoy. Nightattacks depend very much on the prevailing visibility conditions. During poorvisibility, a low lying sub can safely close with its target on the surface.If visibility is good, however, more caution is required.Grayback in the China Sea (Lt. Commander JA Moore)Submerged RadarOctober 21, 1944, Latitude 26-48N, Longitude 124-56E.A very difficult situation. Three radar-equipped escorts are guarding theconvoy! Your best hope is a dawn or dusk periscope attack.---War patrol scenariosThe War Patrol scenarios are the true test of a submariner's skill. Yourmission is to scour the Japanese convoy lanes, finding, attacking and sinkingthe maximum tonnage of enemy shipping. You will encounter a wide variety ofsituations, opportunities and dangers. Note that each submarine is equippeddifferently - your tactics should take into account the strengths andweaknesses of your sub.For an overview of Japanese convoy lanes, see the map. All of these convoylanes are active in scenarios that occur early in the war. As the warprogresses, and the area of the pacific controlled by Japan gradually shrinks,it becomes very difficult to find convoys in areas distant from Japan. In thescenarios that occur later in the war, it is easiest to find targets in thewaters around the islands of Japan.---TorpedoesPrimary submarine armament consisted of six torpedo tubes forward and fourtubes aft. A total of 24 torpedoes were carried: 14 forward and 10 aft. Atorpedo reload required about 10 minutes.Most torpedoes were fired at a range of 1000-3000 yards. The best torpedotrack was one which was perpendicular to the course of the target ship. Thisprovided the largest potential target area. Head-on shots or stern shots wereunlikely to hit their targets.Torpedo data computerThe TDC, when fed with the target speed, range and course, automaticallycalculated the correct torpedo track. The captain would often aim slightlyahead or behind the target ship if he expected a particular change in course.Frequently a "spread" of torpedoes was fired by aiming one slightly ahead ofthe target, one directly at the target, and one slightly behind the target.It was important to make the first set of torpedoes count. Once the torpedotracks were spotted, the convoy would begin to zig-zag radically and theescorts would charge in on the sub's position.Deck gunThe deck gun was effective in sinking badly damaged targets or to slow a shipand force it to fall behind the convoy. The gun was also used as a last ditchmeasure by subs which were forced to surface.ATTENTION COMMANDER: The gun may only be fired when your sub is on thesurface. Use the crosshairs on the periscope/binocular screen to aim the gun.The range is automatically set to the TDC range of the target at which you areaiming. Press the player 2 Control Pad UP or DOWN to add or subtract deflectionfrom this range. Example: an 18 knot destroyer coming directly towards youfrom 4000 yards away will move over 200 yards in the time it takes the shellto hit the target. Therefore you should press the Control Pad DOWN to selecta deflection of -200 to -250 yards before firing the gun. At 2000 yards theshell will only take half the time to reach the target, so a -100 yarddeflection should be used. Your gun is supplied with 80 shells.---Japanese convoysJapanese shipping generally travelled in small convoys of three to sevenships. Convoys consisted of cargo ships, troop ships, tankers and destroyerescorts.Tankers were the most important target class. The Japanese were criticallydependent on the flow of oil to keep the Main Battle Fleet in operation.Troop ships were also important targets. You are more likely to find thesevaluable ships sailing through the shipping lanes which lead directly toJapan.Cargo ships represented the majority of Japanese shipping. They hauledsupplies and equipment to and from the Japanese homeland.Escorts came in two classes. Destroyers were often used for escort duty. TheJapanese also constructed a special class of escort for anti-submarinedefense: the "Kaibokan". This sub killer extraordinare was packed withsophisticated radar and special depth charges. A submarine's best chanceagainst a Kaibokan was to outrun it on the surface, since its top speed wasless than 20 knots. Destroyers could steam at close to 30 knots.Japanese convoy traffic tended to concentrate along the routes between majorports. Refer to the convoy route map above for details.Submarine tacticsA successful submarine attack was very much a team effort by the entiresubmarine crew, with the captain making crucial decisions which spelled thedifference between success or failure. Carefully weighing the number ofescorts, the types of ships, visibility, water depth, number of torpedoesremaining, battery charge, the convoy's course and speed he decided how, whenand where to attack the enemy.With their low surface profile and ability to submerge, stealth and surprisewere vital ingredients in all submarine attacks. Once an enemy ship or convoyhad been spotted, a successful attack required a well thought out approach towithin a few thousand yards or the enemy without being detected.---EscapeIf detected by enemy escorts, escape became the sub's main objecting. Asubmarine was no match for even a single destroyer in a gun and ramming duel.The usual tactic was to dive a deeply as possible and rig for silent running.Maintaining a minimum profile and minimum running noise was especiallyimportant under these circumstances. A strong temperature gradient could alsoprovide some protection from the enemy's sonar. Leaking fuel or machinerydamage made the escort's job easier.Submarines gained some benefil from their tighter turning circle and abilityto constantly track the escorts propeller noises. Under extreme circumstances,a sub might try to convince the attacking destroyers that it had beendestroyed by releasing oil and debris which floated to the surface. (Referabove for this procedure.)At night the sub's 20 knot surface speed was sometimes sufficient to outrunpursuing escorts.Advice to the captainMake sure you understand the role of the Torpedo Data Computer (TDC) - mosttorpedo shots should be made with the periscope crosshairs directly on yourtarget.Make sure you understand the distinction between BEARING and HEADING. BEARINGis the direction in which your periscope/binoculars are looking. HEADING isthe direction your sub is facing. Note that it is generally much faster andeasier to aim your torpedoes and gun by rotating the periscope (changing yourBEARING) rather than by steering the sub (changing your HEADING).In general, you should plan on making a submerged attack in daylight, and asurface attack at night. During dawn and dusk you can try both.