Tactics of aircraft torpedo attacks.

Discussion in 'The War In The Air' started by Peter Clare, Apr 8, 2009.

  1. Peter Clare

    Peter Clare Very Senior Member

    Having recently posted a thread relating to the torpedo attack on Gneisanau by F/O. K Campbell VC I thought I'd post a few details concerning the complexities of using said weapon.

    Relevant to September 1942.


    TACTICS OF AIRCRAFT TORPEDO ATTACKS INTRODUCTION

    The torpedo is the most promising anti-ship weapon and its use by aircraft is undergoing extensive development and likely to become much more frequent. The following paper gives a resume of the tactics which are likely to prove successful.

    Factors of success

    2. The success of a torpedo attack depends upon:-
    (i) Degree of surprise attained.
    (ii) Weight of attack.
    (iii) Quick final appreciation of the situation on sighting the target.
    (iv) Correct positioning of aircraft prior to, and during attack, including diversions.
    (v) Speed and co-ordination in delivery of the attack to counter the enemy's avoiding action and confuse his A.A,
    (vi) Determination in pressing attacks well home.
    (vii) Standard of training and practice.
    (viii) Effective preliminary reconnaissance and intelligence.

    DROPPING THE TORPEDO

    3. To ensure a true run a torpedo must fulfil two conditions at -the moment of its
    entry into the water. Its axis should lie slightly nose up to its trajectory
    at the centre of gravity, and also it should be between 12° - 24° below the horizontal. If the speed be increased, the trajectory becomes flatter. The torpedo must then be dropped from a greater height in order to enter at the correct angle. The height and speed of release are, therefore, closely related. Thus at the moment of release, pilots must concentrate on flying straight and Ievel, at the correct height and airspeed.

    METHODS OF SIGHTING

    4. The theory of torpedo sighting is fully explained in A.P.1730c. Briefly, the problem is to direct the torpedo ahead of the target the distance that the target will cover during the torpedo's run. These are three techniques in being, namely -
    Straight running
    Gyro angling
    Constant bearing.
    (i) In the straight running technique, the torpedo runs straight through the water in the same direction as that in which it was dropped. A sight has to be used to solve the velocity triangle.
    (ii) The gyro-angling technique Involves dropping the torpedo aimed straight at the middle of the target, but as soon as the torpedo enters the water a mechanism comes into play which turns it through a predetermined angle, effecting interception. A computer is required to determine the angular setting on the torpedo.
    (iii) The constant bearing technique causes the torpedo, after release, to maintain a constant bearing relative to the target, both during the flight in air and run in water. This requires both aim-off and gyro-angling.
    The only technique at present used by the R.A.F. is the straight running method.
    5. Experience has proved beyond doubt that accuracy is greatly increased when
    aiming equipment is used. It is therefore most important to use such equipment if it is available.

    FACTORS AFFECTING TACTICS
    Torpedo Force

    6. The objective of the torpedo striking force is to put as many torpedoes into the target in as short a time as possible. To do this the striking force must be manoeuvred so that the maximum number of torpedoes is released and running at the target simultaneously. These torpedoes should be dropped from within the most favourable sectors as is practicable consistent with the disposition of the enemy vessels.
    7. R.A.F. torpedo aircraft are unable at present to carry out high diving
    attacks. Therefore, the approach to attack must be made at low level. The advantage of escaping R.D.F. or visual detection until the last minute offsets to some degree the disadvantages of decreased visibility and of being unable accurately to determine the enemy's heading and disposition.
    8. In attacking a well escorted target, it is desirable to do so in co-operation with bomber and fighter aircraft, but the torpedo should be regarded as the primary weapon. The attacks should be co-ordinated so as to provide the greatest confusion and allow the torpedo aircraft freedom of action. Fighter aircraft should provide air escort for the-torpedo bombers and also attack the escorting destroyers and flak ships.

    Enemy Force

    9. The commander of the enemy force may be able to employ the following defen­sive measures:-
    (i) Land based or ship-borne R.D.F.
    (ii) Fighter protection.
    (iii) Escort vessels.
    (iv) Avoiding action.
    (v) Smoke.

    INFORMATION REQUIRED WHEN PLANNING AN ATTACK

    10. When planning the attack the following information is desirable:-
    (i) Details of target and escort, including disposition.
    (ii) Position, course and speed of the enemy.
    (iii) Probable weather and sea conditions obtaining at position of attack.
    (iv) Extent of enemy R.D.F.
    (v) Probable enemy fighter opposition.
    (vi) Disposition of own forces and any other vessels in the vicinity.
    (vii) Depth of Water.

    For attacks of shipping in harbour, the following details are also necessary;—
    (viii) Topography.
    (ix) Heading of ships.
    (x) A.A., balloon and net defences.


    DAY ATTACKS ON WELL ESCORTED TARGETS

    Cruising and approach formations

    11. The striking force should fly in open formation in sub-flights of three.
    Waves of three sub-flights should fly within one mile, or visibility distance
    (whichever is the less) of each other, and each •wave should be handled indepen­
    dently by its leader, but should conform to the movements of the leading wave.
    The height should be the minimum possible without causing undue fatigue, and
    experience has shown that 50 feet is a suitable cruising altitude. When in the
    vicinity of the target, each wave should manoeuvre so as to develop successive
    attacks in the shortest time possible. The ideal is to approach to a position
    5-10 miles ahead of the target from which to develop the attack.
    12. It may be possible to home on a shadowing aircraft at the required position,
    otherwise normal navigation methods aided by A.S.V. should be employed.
    Accurate navigation of a force flying at 50 ft. is not easy and correct calcula­
    tion of windspeed and direction is essential. Windspeed and direction are
    normally found most accurately at this height by observation of wind-lanes on
    the surface of the water, checked by drifts. It is emphasised that if a
    successful interception is to be carried out, the navigation must be particu­
    larly accurate, to ensure that the target is met on a bearing which is most
    suitable for the torpedo attack.
    Action when the Enemy has been located by the Striking Force
    13. As soon as the leader has definitely located the target, he must decide whether to lead straight in to attack, or manoeuvre to approach from a more fav­ourable angle.
    This decision will be influenced by the following!-
    (i) Importance of surprise effected.
    (ii) Desirability of intercepting and developing the attack from ahead or astern of the enemy.
    (iii) Presence of enemy fighters.
    (iv) Approach from the darker side of the sky, when dawn and dusk attacks are carried out
    (v) Approach from the direction of the low sun in a clear sky will give the greatest chance of surprise, and may hamper control of A.A. fire.
    (vi) Use of relative wind to best advantage,
    (vii) Avoidance of outlying enemy ships.
    (viii) Topography of coast if in vicinity.
    Formation and Directions of Attack
    13. The formation which has proved most promising is that of aircraft flying in sub-flights of three, in squadron inverted vie. The three directions of attack visualised, based on this formation, are:

    (i)from ahead;
    (ii) from abeam
    (iii)from astern

    (iv) Optimum Bearings
    15. The best chance of hitting a ship with a 40 knot torpedo dropped from 1,000 yards will be achieved if it is dropped -within the following arcs of relative bearing from the ship :-
    (i) Ship on a steady course - 30° - 80° either side.
    (ii) Ship swinging away - 10° - 60° on outer bow.
    (iii) Ship swinging towards - 70° - 120° on inner quarter.

    Attack from ahead

    16. The method of approach is. If, as is usual, the ship takes avoiding action the sub-flight furthest on the bow must increase speed to a maximum as soon as this avoiding action becomes apparent and endeavour to head off the ship. Sub-flight attacks should be as nearly simultaneous as possible. Aircraft attacking a fast target from dead ahead or nearly so with Duplex set pistols, should not drop at less than 900 yards in order that the pistol may arm.

    Attack from the beam

    17« When it becomes apparent that the wave is committed to a beam-on approach, the sub-flight furthest on the bow should increase speed to the maximum and endeavour to pass ahead of the target and attack on the opposite bow.

    Attack from astern

    18. If the approach has to be made from astern of the target, the formation
    should open out on a front of 8,000 - 10,000 yards, (minimising the risk from
    light A.A.). As an approach from the quarter may be difficult and prolonged,
    the two outer sub-flights should increase speed and open well ahead of the target,
    particularly if it is moving fast, before turning into attack. The third sub-flight should continue straight towards the stern of the target ready to take advantage of any avoiding action. It should be remembered that torpedoes dropped from astern, or on the quarter will have to travel a greater distance in the water before striking and the dropping range should be shortened accordingly.

    The Getaway

    19. The getaway should be made at low level, but high enough to avoid splash
    barrage. The direction should be governed by the following two factors:-
    (i) Necessity for opening range.
    (ii) Complications produced in the sighting problem of the A.A. gunners by changes in altitude and varying rates of change of bearing.
    A high relative change of bearing is normally achieved by turning in a direction astern of the target. The general direction of withdrawal should have been determined prior to take-off and torpedo aircraft should pass through a rendezvous specified by bearing and distance from the target.

    CONVOY ATTACKS

    20. When the target is a small convoy in more than one column, the most convenient striking unit is six aircraft.
    21. The aircraft should endeavour to attack on each beam, selecting the largest ship in the convoy. There are advantages in choosing a dropping position which


    places the bow of the target ship in line -with the stern of a ship in the next column, or, alternatively, the stern of the target ship in line -with the bow of a ship in the next column. This effectively increases the chances of obtaining a hit.

    AIRCRAFT CARRYING TWO TORPEDOES

    22. When aircraft carry two torpedoes, these should be released in the same attack at an interval of half to one second.

    NIGHT ATTACKS

    General Conditions

    23.(i) In a well delivered night attack, the aircraft are rarely sighted
    before making their attack, which can therefore be -well pressed home.
    (ii) A.S.V. is of the greatest assistance to night-striking forces both in locating the target, and in manoeuvring so as to attack from the most favourable direction.
    (iii) Night attacks can be carried out either on dark or moonlight nights. On bright moonlight nights aircraft can attack up moon •without using flares, but on dark nights reconnaissance flares are necessary to silhouette the target.

    Moonlight Attacks

    24.(i) The striking force should consist of sub-flights of 3 aircraft des­
    patched at intervals of about 30 minutes.
    (ii) The attack should be carried out from the down moon side of the target.
    (iii) Aircraft should lose height in a shallow dive with engines throttled back, and make their final approach at dropping height or in a shallow glide.
    (iv) They should attack in succession from the same direction. Attacks should be well pressed home at a normal range of 600 yards, but drops should not be made at less than 600 yards when duplex pistols are used from fast aircraft.
    (v) The attack should not be hurried, and if heavy and accurate A.A. fire is encountered in the preliminary approach, aircraft should stand off and make another approach.
    (vi) Successive aircraft should take advantage of the confusion caused by earlier attacks.
    (vil) The getaway should be made in a direction clear of following attacks.

    Dark Night Attacks

    25.(i) A convenient unit for dark nights strikes consists of 1 flare dropping
    aircraft to act as leader, and 3 torpedo aircraft who can, if necessary, home on
    the leader.
    (ii) The leader at least, should have an A.S.V. equipped aircraft.
    (iii) A height of 3,000 - 4,000 ft. is suitable for night striking forces on passage.
    (iv) When aircraft are employed in which night formation is impracticable, it will be necessary for them to proceed singly at one minute intervals.
    (v) One flare dropper per three torpedo aircraft is. necessary and all air­craft should be equipped with A.S.V.

    Illumination of the Target

    26.The target illuminating aircraft should carry the maximum number of flares
    and A.S.V. There are two methods of employing the illuminating aircraft:-
    (i) By despatching the aircraft in advance of the striking force, to take over the target from the shadowing aircraft.
    (ii) By detaching the illuminating aircraft from the striking force on arrival in the vicinity of the target.
    27.In either case the target is illuminated in the same manner. The illumina-
    ing aircraft proceeds to the side of the target remote from the direction of
    attack. When ordered by the leader of the striking force, this aircraft drops
    a curtain of about eight reconnaissance flares at right angles to the direction of attack, about one mile from the target. A second curtain is then dropped at right angles to the first on a loading towards the targets expected track-, to ensure silhouetting the target if it alters course. In practice the sixteen flares are usually dropped in an arc which produces the same result in a more practical manner. Flares must not be dropped on the side of the target from •which the attack is to be delivered. Aircraft should, if possible, avoid flying between the flare curtain and the target.
    The following points are important:-
    (i) The period between illumination and attack should be kept to a minimum in order that the enemy may not have time to develop defensive measures such as increasing speed or laying smoke screens.
    (ii) Wherever possible the sector relative to the target in which the flares are to be laid should be decided at the time that the attack is planned. Aircraft which have temporarily lost the target should thus be enabled to pick it up try approaching the flares on a pre-determined course.
    (iii) One aircraft of the striking force should be detailed as reserve illu­minating aircraft for use in emergency, and should carry as many flares as possible in addition to its torpedo.
    (iv) A curtain of flares must always be used, as single flares over individual ships are useless and misleading.
    (v) A.S.V. is of great assistance in positioning the flares. SMOKE SCREEN
    28.It must be remembered that the laying of smoke screens by ships does prove
    embarrassing to aircraft attacking at night. This is especially the case -where
    the number of vessels in convoy is small and the escort large, thus enabling the
    latter to lay a screen close to, and parallel -with the lines of ships. In these
    circumstances flares should only be dropped if absolutely necessary, and then
    only at the last moment, to reduce the chance of the enemy developing his smoke
    screen.

    DAWN ATTACKS

    29.(i) A dawn attack should normally be made at the first possible light, so
    that the getaway can be completed before it is light enough for fighters or
    effective A.A. fire. Dawn attacks have the advantage that aircraft return and
    land in daylight, but have the disadvantage of making a night passage to the
    target with the consequent likelihood of attacks having to be made singly, and
    additional navigational difficulties.
    (ii) In middle latitudes, depending on weather conditions, it is possible to attack completely unseen between 45 and 30 minutes before sunrise.
    (iii) The attack should be made in line astern, on the night attack principle.


    DUSK ATTACKS

    30. (i) It may be desirable, owing to enemy fighter or A.A opposition, to hold off till dusk before launching a torpedo attack. This should enable torpedo aircraft to press home their attacks.
    (ii) If a striking force arrives at the target just before dusk it may be advisable for it to stand off until conditions, while still suitable for torpedo attack, are dark enough to afford cover. This period depends on varying. conditions, but is roughly 25 to 45 minutes after sunset in medium latitudes.
    (ill) The attack should be made as a day attack, with intervals of about 2 minutes between waves.
    (iv) After the attack no general form up should be made iaircraft should return to base singly.

    PHOTOGRAPHY

    31 • (i) If possible all aircraft of the torpedo striking force should be equipped with F.46 torpedo aiming cameras operated from the torpedo release switch.
    (ii) An F. 24 camera with either 9" or 14." lens should be carried in the leader's aircraft and operated by the wirless operator during the attack, and useful photographs of the target during the approach or turn away from the attack can be obtained. In addition, an P. 24 camera mounted vertically , equipped with a reflecting mirror, may be used. If the camera is started automatically on the release of the torpedo, a series of photographs will be obtained during the turn away, which will probably record the actual explosion when the porpedo torpedo strikes the target.
    (ill) A photographic reconnaissance timed to arrive at the target shortly after the anticipated time of the torpedo "strike" should be provided whenever possible.
     
  2. sapper

    sapper WW2 Veteran WW2 Veteran

    My best friend was a Fairy swordfish torpedo plane piloy the string bag
     
  3. Donnie

    Donnie Remembering HHWH

    Peter,

    My Great Great Uncle was a Torpedo Bomber Air Gunner on Wellingtons. You may be interested to no that a book will be published that details this type of attack (it was written by me and my freind)

    Donnie
     
  4. von Poop

    von Poop Adaministrator Admin

    Everything's more complex than it first appears isn't it.
    I can think of Taranto, and perhaps the attack on the French fleet (?) along with the Gneisenau business described, but my Naval knowledge being if anything sketchier than my aerial; Where else did the british use aerial torpedos to great effect? did they ever sink a submarine with one?
    ~A
     
  5. Donnie

    Donnie Remembering HHWH

    My Uncles Log Book states that on Jan 27 he went on an "Offensive Recce Between Sicily and Tunisia Submarine Sighted 2 Torpedoes Dropped". On that occation they didnt sink it but i think i have referance to them sinking one...

    Any help? Donnie.
     
  6. Drew5233

    Drew5233 #FuturePilot 1940 Obsessive

    Cheers for that Peter.

    I watched a doc the other day by the National Geographic called 'Who sank the Bismarck' and they spoke to a pilot who was one of the crews that attacked her in a Swordfish.

    Three things I remember him saying.

    You had to slow right down prior to release around 80 mph or the torpedo would break on hitting the water.

    The timing of release had to coincide with the waves. It had to hit the water between the waves or the torpedo could be knocked off course as it cut through the crest of the wave.

    Lastly and quite remarkable was his description of the attack. He couldn't aim due to the bad weather so the pilot tapped him on the shoulder and told him he would tell him when to release the torpedo. Then the pilot half climbed out of the cockpit to look at the sea to judge when to release the torpedo.

    What I found even more surprising was he said all the aircraft returned from the attack.

    Cheers
    Andy
     
  7. Zooker

    Zooker Junior Member

    Peter Clare,

    I am a brand new member and I using my first post to thank you for this thread. Very interesting stuff. Any chance you have a link to this A.P.1730c document you reference in your post?

    Thanks again.
     
  8. Smudger Jnr

    Smudger Jnr Our Man in Berlin

    Zooker,

    Hello and welcome to the forum.

    Regards
    Tom
     
  9. Gerard

    Gerard Seelow/Prora

    Hi Zooker and welcome!
     
  10. Zooker

    Zooker Junior Member

    Thanks for the welcome guys. Great board you got here. Lots of good info.
     
  11. Peter Clare

    Peter Clare Very Senior Member

    Peter Clare,

    I am a brand new member and I using my first post to thank you for this thread. Very interesting stuff. Any chance you have a link to this A.P.1730c document you reference in your post?

    Thanks again.



    Hi Zooker.

    Welcome to the forum.

    Sorry I do not have a reference link for the subject, the post comes from my copy of the document AIR41/47 (RAF Narrative Vol.III) appendix XXXI

    Regards
    Peter
     

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