Dive bomber or torpedo bomber?

Discussion in 'World War 2' started by vashstampede, Nov 25, 2012.

  1. vashstampede

    vashstampede Active Member

    When it comes to aircraft against ships, which one was better at the job?
    Dive bombers or torpedo bombers?

    Bismark was hit by a torpedo from a torpedo bomber, which started its downfall.
    USS Yorktown was hit by at least two bombs from dive bombers but the damage was patched up fairly quick, it was sunk after hit by two torpedoes.
    All four Japanese carriers in the Battle of Midway were sunk by dive bombers, multiple waves of American torpedo bombers attack were ineffective.
    Germans have very good dive bombers, but lacked? of dedicated torpedo bombers. Would they do better against allied ships if they had torpedo bombers?

    So which one is better against ships during WWII? Dive or torpedo?
    If you know any other ships sunk scored by either, please bring them up. :)
     
  2. R Leonard

    R Leonard Active Member

    Part I

    A difficult subject with bunches of factors to consider.

    To bring up a few . . .

    - Effectiveness of attack profile of a given aircraft type against warships versus effectiveness against merchant vessels
    - Effectiveness of attack profile of a given aircraft type against warships with air cover versus warships without air cover
    - Employment of armor piercing bombs versus semi-armor piercing bombs versus general purpose bombs versus torpedoes
    - Relative survivability of aircraft types in the presence of varying defenses
    - Overall versatility of aircraft types – the biggest bang for the expenditure of production effort, aircraft in combat, and crews.
    - Effectiveness of the weapon deployed – was it even worthwhile to drop a torpedo knowing its probability of even hitting the target
    - Effectiveness of air delivered torpedoes designs; US versus Japanese versus British versus German versus Italian versus Russian (yes, Russians, and they were rather good at it)
    - Doctrinal-tactical considerations and modes of attack, including dive bombing versus glide bombing versus something in between those two versus traditional torpedo attack profiles
    - Supported versus unsupported attacks
    - Stationary versus moving targets
    - Day versus night operations
    - Torpedo plane only attacks versus coordinated attacks combining dive bombing, fighter suppression and torpedo drops, day or night.

    - any combination of the above plus any others one might raise.

    The discussion becomes a matter of which of these factors one wants to discuss. Most of the serious service discussion I’ve seen has been more related to survivability of aircraft and crews for the results obtained. Other than that, the issue can also be one of what would be the most effective attack profile, as mentioned above, that is what method is more likely to achieve the desired results, damage to or loss of enemy warships and shipping, dive bombing, glide bombing, of torpedo launch.

    Also, I’d point out that Yorktown was considered to be salvageable and the USN was in the process of effecting steps to stabilize her list and tow the ship to Pearl Harbor when she was hit by two torpedoes launched from a Japanese submarine on 6 June 1942. Those submarine launched torpedoes are what sank the ship, not the air delivered torpedoes of 4 June.

    To quote an USN pilot who flew combat at Midway: “Torpedo plane pilots and crews had the most self-sacrificing mission in US naval aviation, not just there but through the entire war.”

    It is fairly obvious that the quickest way to sink any ship is to poke a hole in the side and let the water in. Torpedoes, when everything falls together correctly and the gods are smiling on you, perform this task in an admirable fashion. On the other hand, a well executed dive bombing attack can just as often produce the same result, though usually from secondary damage. A successful glide bombing attack can poke some really nice holes in hulls that can let in copious quantities of water.

    There were more than just a few ships, capital warships, merchant ships, other warships, sunk by air delivered torpedoes, probably an equal number struck by same that did not sink, and an even bigger number that were targeted but not hit. The most successful attacks, especially against maneuvering targets, are those approaching on more than one axis, essentially negating maneuver as factor. If you can’t make such an attack in sufficient numbers, then odds are your attack will fail, though one can always find the exception to the rule.

    Dive bombing, even glide bombing does not quite suffer from the same problem, although deflection to the angle of attack is a problem. One strives to dive stern to bow which tends to limit the deflection aspect and if the ships captain guesses wrong can have him turn right into a bomb which might have otherwise missed. Dive bombing also means a ship has less time to maneuver out of the way and AA fire tends to be less effective.

    One might note that in the last month of strikes on the Japanese home island, while chasing down and destroying most of the remnants of the Japanese fleet, not a single torpedo was expended, not one. All the work was performed by dive bombers, fighters carrying bombs, and torpedo planes carrying bombs, but no torpedoes, even against stationary (and, indeed, most of them were stationary) targets. There was not much left after the completion of several strike days.

    One also might note that on 1 June 1945 an order was issued to the US fleet to remove all Mark 13 torpedoes from storage aboard escort carriers. This left their organic torpedo planes, about 12 per ship, with nothing to deliver but bombs, depth bombs, or, if dedicated for ASW work, Mark 24 FIDO homing torpedoes – a rather potent little device of itself, poking holes in a submerged submarine is very, very effective in bring about its demise.

    To be continued . . .
     
  3. R Leonard

    R Leonard Active Member

    Part II

    Similarly, by the end of the war the staffs of the Fast Carrier Task Forces were pushing hard for bomb toting fighters to replace both dive bombers and torpedo planes, opting for the versatility of a fighter able to haul 1000 lbs of bombs as far as either of the other two types. From message traffic from Commander Task Force 38 to addressees on 12 June 1945 (this message was produced by the TF38 Ops staff led by one Capt James S. “Jimmie” Thach):

    120245 CTF 38 VIA COM3RDFLT TO COMAIRPAC INFO COM5THFLT, CINCPOA BOTH, COM1STCARTF, COM3RDFLT ComAirPac 292035.

    The early 1942 concept of carrier striking force continues to have undue influence on front line equipment and concomitant supply. Planning should recognize instead the actual needs of present and future operations in this war. CVs will never get far from beachhead when the real invasion begins because they are the only source of close CAP and support. For this work VF and VBF are practically the only useful type. Under the control of CASCUVT and VB now aboard have been used only for supply missions and for bombing and strafing where antiaircraft is ineffective. These types are more vulnerable to AA than are VBF when excursions into strategic activity are made. VBF properly and understandingly handled can carry greater punishment to the enemy over longer ranges than the VB type. The foregoing is the experience of the last year and emphatically of the immediate past. The compelling advantages of single seat bombers (VBF) over multi place bombers (VSB-VTB) in every prospective type of carrier operation are demonstrated in CTF 38 serial 01310 dated 27 May. Even after this war our CV and CVB complements will likely be designed at least for some years for operations in littorals against shore based air rather than against navies.

    Complements of the CVBGs should have the same high proportion of single seaters as is recommended herein and has been recommended previously CVs. The present complement alternate complement and proposals A through D of ComAirPac’s 292035 are not recommended as they do not realistically meet the needs of operations planned for this task force. The single seater will continue to predominate during this war. Production and supply should be altered forthwith to accommodate. Training needs no appreciable change. New and better types of VF are of course welcome. Recommend CVBG and CVG complements to occupy the following proportions of ship capacity. VF (F8F when available) 30%, VBF (F4U) 60%, special (F7F) 10%.

    I would suggest that the opinions of the folks on the pointy end of the stick form the answer to the question, though in truth one might consider that their opinion, at that point, indeed, just about ever since, was driven by the simple fact that there were no opponents at sea worthy of a aerial torpedo attack, a mission in today’s world seems quaintly archaic as there are plenty of sea skimming missiles that can do much better job. Nor were they particularly tuned into the BuAer coming decision that F7Fs really weren’t for carrier work unless there was a really pressing reason.

    Note, though, the recommended complements are all fighter aircraft with a heavy emphasis on the bomb carrying capability of the F4U. For those unfamiliar with the USN’s alphabet soup of acronyms:

    CASCU is a Combat Air Support Control Unit, of which the USN and USMC had a few – though the Marines dropped the obvious “Combat” at the beginning of the acronym and called them ASCU’s - charged with coordinating air to ground support.
    CVG is an air group assigned to a fleet carrier, usually of the Essex class.
    CVBG is an air group assigned to a large fleet carrier of the Midway class.
    CTF 38 was VAdm McCain, Commander Task Force 38, also known as 2nd Fast Carrier Task Force.
    COM3RDFLT was Adm Halsey, Commander 3rd Fleet.
    COMAIRPAC was VAdm Towers, Commander Naval Air Forces Pacific.
    COM5THFLT was Adm Spruance, Commander 5th Fleet.
    CINCPOA BOTH refers to FAdm Nimitz and his advanced HQ at Guam and his administrative HQ at Pearl Harbor.
    COM1STCARTF was VAdm Mitscher, Commander 1st Fast Carrier Task Force, also known as Task Force 58.
    VBF is a generic reference to an aircraft or squadron type – Bombing/Fighting; in more common parlance “fighter bomber”. VBF squadrons were made up of either F6Fs or F4Us, often largely populated with pilots dragooned from VB or VT squadrons.
    VF is a generic reference to an aircraft or squadron type –Fighting; in more common parlance “fighter”. VF squadrons were made up of either F6Fs or F4Us, except for, there at the very end, VF-19 working up in Hawaii which was equipped with nice new F8Fs.
    VSB is a generic reference to an aircraft or squadron type – Scouting/Bombing. A somewhat archaic construction, at the start of the war US fleet carrier’s, other than USS Ranger, complements included a VS (Scouting) squadron and a VB (Bombing) squadron. Starting in March 1943 all the carrier VS squadrons were re-designated as VB squadrons, often involving a numbering change as well. For examples, VS-10 aboard Enterprise became VB-20 and VS-11 at Fiji enroute to the Solomons became VB-21. The shore-based inshore district patrol squadrons lost their distinctive district-detachment designations and adopted the VS designation. Upshot was that after this changeover, carriers no longer carried VS squadrons. The VSB referred to in this message were VB “Bombing” squadrons equipped with the SB2C.
    VTB is a generic reference to an aircraft or squadron type – Torpedo/Bombing. Reference here is to VT (Torpedo) squadrons operating the TBM Avenger which was dual purpose, torpedo and bombing. The TBM was the Eastern Aircraft version of the Grumman TBF which was the replacement Douglas TBD.

    Of course in the long term things did not exactly work out the way the Fast Carrier Task Group ops guys wanted in their message. Post war planning included torpedo planes and dive bombers in projected air group complements, however, by the late 1940s the VB and VT missions had been combined into a single new squadron designation, VA, the attack squadron. The dedicated torpedo plane and the dedicated dive bomber became a thing of the past. New single seat aircraft – the USN eventually settling on the Douglas AD Skyraider series – could handle both jobs, though the AD's final reputation was made as the A-1 bomb hauler, serving well into the Viet Nam years. By 1951 carrier air groups were made up of VF fighter squadrons (usually F9F Panthers and F4U Corsairs), VA squadrons (usually AD variants) with various detachment of two to four planes from specialized squadrons for night fighters, night attack, AEW, photo recon, and ASW, not to mention a couple of helicopters. For example, aboard USS Bon Homme Richard in September 1951 was CVG-102 consisting of:
    VF-781 (12 F9F-2 – fighter-bomber),
    VF-783 (15 F4U-4 – fighter-bomber),
    VF-874 (15 F4U-4 – fighter-bomber),
    VA-923 (18 AD-3 – attack bomber),
    VC-3 Det. (4 F4U-5N – night fighters),
    VC-11 Det. (3 AD-4W – early warning/radar),
    VC-35 Det. (2 AD-4N -night attack), and
    VC-61 Det (3 F9F-2P – photo recon).

    No dedicated torpedo planes, but lots of bomb hauling capability. And dropping torpedoes generally? Well, that pretty much went away, too. After WW2, the only time USN attack aircraft dropped torpedoes in a combat situation was to render in operable the sluice gates of a dam in North Korea, a successful mission, by the way.

    See, also, for example, http://www.navweaps.com/Weapons/WTUS_WWII.htm for basic info on US torpedoes including the Mark 13 and the Mark 24. The article brings out the problems with the Mark 13 Mod 1 version. Historically, the Mark 13s used in the early US carrier raids and up through Coral Sea were Mark 13 Mod 0, the production run before the Mod 1’s. Folks on the scene with whom I’ve spoken, at least those aboard USS Yorktown, were consistent in their observation that these Mod 0’s were babied, subjected to constant preventive maintenance, upkeep and testing. Up through Coral Sea, while being delivered by the obsolescent Douglas TBD (of the type massacred at Midway a month later) these fish, with the exception of speed, a constant problem with the entire series, had a fairly reliable performance and notable successes, including one Japanese light carrier.

    Regards
     
  4. vashstampede

    vashstampede Active Member

    Well, it is a fact that (if) score a hit, a torpedo hit below waterline usually does more damage than a bomb dropped from the air. It is because the water doesn't compress, and once a torpedo hit it acts like a shaped charge similar to how modern anti-tank weapons penetrate tank armor. Not only it has better chance to punch a hole on the ship, the fact the hole is below waterline mean the ship will take in water and sink faster.

    For smaller targets such as destroyer, if a torpedo hit below the ship instead of on the side of the ship, it can directly break the ship's spine into half and sink the ship right away.

    From the point view of survivability of the plane, it is obvious that dive bombers can survive better because they are not forced to fly low in a straight line.
     
  5. Peter T Davis

    Peter T Davis Administrator Moderator

    But, the US had some serious issues with their torpedoes early in the war, IIRC. That, and the way the planes operated made them more vulnerable than the dive bombers.
     
  6. R Leonard

    R Leonard Active Member

    The Mark 13 was a seriously flawed weapon . . . if your targets of choice could easily exceed 30 knots. All one has to do is turn the ship with stern towards the torpedo and then out run it. Yamato did this at Leyte. For the Americans a good deal because Yamato turning away from torpedoes turned away from the action. None the less, Yamato did out run the torpedoes - - - this time. Her sister ship did not do as well in the confined waters of the San Bernardino and was sunk. Yamato did not do so well about 6 month later when swarmed from all directions . . . there was no turning away from an all compass point attack.

    On the other hand, against 10 to 15 knot merchies and naval auxiliaries, the Mark 13 did just fine.
     
  7. vashstampede

    vashstampede Active Member

    What was the speed and maximal range of those torpedoes?
    I always thought they were faster than any ships at the time, just so the ships were able to change course to avoid them.

    How were the torpedo planes attack the same ships from different directions at the same time? Wouldn't it be dangerous for them? The chance of collide in mid-air anyone? :)
     
  8. R Leonard

    R Leonard Active Member

    Torpedo attack Pt I

    While I work as time allows in the background on analysis of torpedo vs bomb delivery stats from the USN in WW2, I will take a short pause to discuss torpedo attack methodology.

    USN torpedo planes, were limited by the performance factors of the Mark 13 torpedo. In many ways the attack executed by a torpedo squadron faced the same problem as that of a submarine. One could not come just come up on the broadside of a moving ship and let fly. The problem is one of putting the torpedo in the water aiming for a place one hopes the target will be base on where it is when the torpedo is dropped – this is called, the technical term, deflection, the not so technical term, lead.

    Dropping the torpedo, taking into account the distance the torpedo has to travel before the warhead arms, about 800 yards, and aiming to where the ship is now, does you no good. With a torpedo such as the Mark 13, with a 33.5 knot maximum speed, means the drop is made about 1000 yards from the target. At a straight ahead run at a stationary target, that means the torpedo will run for about target about a minute before striking the target.

    Of course that presumes the torpedo doesn’t porpoise, sink, veer of course, premature from a surface run, or any other of a long list (sometimes combinations) of things that can go wrong.

    Consider, then, the same 1000 yard range drop against a ship, say a light cruiser, maneuvering at combat speed on a course 90 degrees to the torpedo plane’s approach. The torpedo pilot, clever fellow, recognizes that the target is moving and aims for the bow. Unfortunately, that still will not be good enough. A light cruiser, say of the Nagara class, had a top speed of 36 knots. In a combat situation you can be sure that the captain is calling the engine room commanding “more, more, more!” But, vagaries of bottom fouling and wear and tear on the engine, let’s figure the best he’s going to get is about 35 knots. Note that his speed is already 1.5 knots faster than the torpedo’s maximum speed. The 35 knots also means that the by the time a minute passes from the time the torpedo was dropped, the bow of the ship has already moved some 3450 feet; that is about 6 ship lengths.

    Thus, just aiming for the ship’s bow at time of release will result in a clean miss by about 2800 feet.

    Folks in the torpedo business, aircraft and submarines, were well aware of the problem. Submarines, of course can not only shift their aiming point, but can also crank in a gyro adjustment to the torpedo itself to make it run at an angle to the ship’s track. With torpedo planes, nifty aiming devices, originally mechanical, later electronic, allowed the pilot to correct his angle of approach in order to add in the necessary deflection to have the torpedo reach a point way out in front of the ship at the same time that some piece of the ship is likely to be at the same spot. But to do so he was required to point his aircraft towards that imaginary point.

    This, of course, enters more variables into the problem. Now shooting some where out along the ship’s track means a longer torpedo run, on our case, presuming nice straight lines, now the torpedo has to run about 4 minutes to reach a spot some, now 4000 yards, down range from that first drop point mentioned above. Not too bad, the Mk 13 had a range of about 6200 yards so you’re still within the weapon’s operating parameters.

    But, this really is not very good idea; the longer a torpedo is in the water, the more that can go wrong, and, especially, the longer yon ship captain has to react to the situation

    . . . you are now hopefully now picturing a three dimensional problem in your head.

    One way to shorten the time in the water is to actually fly down the bearing you want the torpedo to take. Well, that means turning to a slightly intersecting course with the cruiser’s course . . . certainly a problem because now the plane is effectively broadside to the cruiser and subject to the tender attentions of its antiaircraft suite. The problems just keep mounting. This grave situation exists as the plane, as of necessity for targeting purposes, passes ahead of the ship . . . remember, the plane is traveling at least 3 times the speed of the ship. And by this time, the cruiser’s captain, no idiot and certainly knowledgeable himself about torpedo targeting, says to himself, “Ah ha, this clown is going to make a drop somewhere where he thinks I’m going to be,” and promptly executes a 90 degree turn, spoiling the whole plan.

    Frankly, one really has to catch someone with his pants down to execute a successful single plane attack on a moving warship. Merchants and naval auxiliaries might be a little easier, they are certainly slower.

    More to follow . . .
     
  9. R Leonard

    R Leonard Active Member

    Torpedo attack Pt II

    This is why torpedo squadrons are divided up into divisions and sections. In USN VT doctrine, torpedo attacks against capital warships usually dedicated at least half, and for really worthwhile targets like battleships and carriers, an entire squadron to a single attack. Why so many? Well, for starts, we already know that at least half the torpedoes dropped will suffer some malfunction . . . that is a given . . . so a 12 plane squadron would expect only 6 torpedoes to run “true.” And what of the above question as to the danger of collision? Well there’s always a danger of collision, but remember that this sort of formation flying and tactical formations and actions are routinely practiced, over and over. No, there was no particular danger of collision. Torpedo attacks by a trained squadron were not willy-nilly affairs; everyone knew where they were supposed to be and how to maintain formation.

    Presume for a moment an attack on an opposing carrier. Forgetting for the moment about escorts and defending CAP and other clever impediments to a torpedo attack, here is a carrier pounding along at about 33 knots, just slightly less than the top speed of the torpedo. - - remember those terrible word problems? If a car leaves city A bound for city B at T1 time and S1 speed how long does it take a car leaving at T2 time and traveling at S1+X speed to catch up? - - same deal here. Half a knot does not buy much in overtake capability. This means that one has a choice. Launch aiming for some point out in front of the ship while moving somewhat parallel and, maybe, slightly ahead of the ship OR approach from the carrier’s bow and launch for a much shorter run where the torpedo approaching from the front intersects the ship’s course.

    Of course, all by itself, the carrier captain is going to see you and take evasive action. This is where the multiple plane attack enters the picture. The navies operating torpedo planes all had the same solution to the high speed targeting approach.

    The basic attack was the “Anvil.” In this attack method, executed ideally either from a bow on approach or a stern following approach, half of the attacking planes approach on the port side of the target and half to starboard.

    With the stern attack, the attacking element approaches on both sides from abaft the beam of the carrier, bracketing, and when abeam, or, better, slightly drop torpedoes slightly angled to intersect carrier’s track. (Remember, you want to minimize the time your torpedoes are in the water, both in terms of reaction time and the device’s range, so with the stern approach the abeam position would be, of necessity, pretty close to the target, like in the neighborhood of 500 yards . . . spitting distance for a 12.7 mm machine gun mounted amidships.)

    From a bow on approach, attacking elements approach in the opposite direction from the carrier’s track closing on both sides of the bow. This is a somewhat safer approach as fewer defending antiaircraft batteries can be brought to bear. The approach does require some delicate timing as the elements must ensure that the dropped torpedoes will travel a sufficient distance to arm the warheads. At the appropriate point, though, the element drops the torpedoes, again angled towards the carrier’s track and taking into account the ship’s speed and then breaks away, thus avoiding the ship’s broadside batteries.

    In both of these methods, the object is to have a spread of torpedoes approaching the carrier’s track, to intersect at a point of impact based on the ship’s speed. The happy part is that the multiple torpedoes presents a problem very hard to solve with ship handling, a turn to either side puts the ship in danger of running into a torpedo and to keep going straight leaves the same danger.

    This is the classic torpedo plane attack method. It requires six to twelve planes and, now taking into account escorts and CAPs, is very hard to execute. Just getting into position can be extremely hazardous.

    Take for example the 12 planes from VT-3 at Midway. Closing from astern on the maneuvering Hiryu, LT Pat Hart, the executive officer, led half the squadron in an arcing track to the left so as to come up on the ship’s port beam. They never made it, all were shot down by CAP and AA fire. The squadron commander, LCDR Lance Massey, led his two divisions from the abaft position to close on the starboard beam. Four of the six were shot down, including Massey, and the other two were forced to make their drops early and break away. No hits scored and the two surviving planes were forced to ditch from damage as they returned to the vicinity of the US carriers. Two pilots and one of the two rear gunners survived.
     
  10. aghart

    aghart Former Tank Commander Moderator

    HMS Prince of Wales & HMS Repulse, sunk by land based twin engined Torpedo Bombers off Malaya on 10th December 1941. The first capital ships sunk purely by air attack whilst at sea and able to manouver.
     
  11. vashstampede

    vashstampede Active Member

    From the battle records, it looked like the Japanese had better luck with torpedo bombers. The American torpedo bombers suffered heavier losses for little to no result.

    Why did U.S. military keep using torpedo bombers if the results were unsatisfactory?

    By the way, when was torpedo bombers completely phased out?

    If I remember right, the torpedo bombers from Midway were separated from their escort fighters when the fighters went off to fight the incoming Japanese bombers heading for the Midway. Those unescorted torpedo bombers were all sitting ducks for CAP. It might have been different if their escorts were with them so the Japanese CAP had to divert their attention to fight off the escorts instead of comfortably shot down the torpedo bombers like a shooting game.
     
  12. R Leonard

    R Leonard Active Member

    Not being particularly willing to write up a history of air operations at the Battle of Midway, I would note that there are plenty of very good, and some of them massive, tomes which cover the entire period, not to mention on-line available unit and fleet reports.

    No offense, but your description is somewhat muddled.

    US aircraft attacking the Japanese with torpedoes, B-26s & TBFs out of NAS Midway and TBDs from the carriers, with the exception of one squadron, were all faced with the daunting task of making their attack runs with no fighter support. Their losses tell the tale, 2 of 4 B-26s lost, 5 of 6 TBFs lost, 25 of 29 unsupported TBDs lost (plus one more stricken for damage on its return), and even with the one fighter supported squadron, 10 of 12 lost and the last two forced to eventually ditch due to damage in the vicinity of the US TF-17.

    As to the whys and wherefores of the lack of fighter support in those attacks lacking same, I refer you to the literature (and I will happily provide a list of books and reports for your future research); it is a long story, not one which lends itself to an internet forum format.

    As far as the one fighter supported TBD attack (VT-3 from Yorktown) it is simply the sad fact that 6 (actually 5, as one was shot down in the opening moment of the engagement) fighters against a CAP of some 30 to 35 fighters can lead to a predictable outcome as far as protecting their charges is concerned.

    On the flip side, and again the literature covers this quite nicely without recounting the sequence of events in detail here, the Japanese torpedo attack against Yorktown came in on a ship already not at 100% functionality, a disjointed and piecemeal CAP interception, and accompanied by a fighter escort that took advantage of the US CAP situation. One might note that at least four, possibly more, of the attacking Japanese torpedo planes were shot down by fighters launched from Yorktown directly into the face of the attacking torpedo planes on their final runs, this after their blowing through the deployed CAP.

    None of these are simple easily described actions, especially in a forum with a 10K character per post limit. It would be better to bone-up on the Midway subject yourself. In my humble opinion, time spent reading is better spent than time spent looking for quick answers from someone else’s head on the internet.

    The same could be said of the evolution of US VT doctrine and technology over the course of the war, although it has been touched upon briefly in some of the above posts. I did, in fact, complete a rather superficial analysis of USN VT operating results versus VB results. You won’t see it posted here as it ran 10 pages single spaced . . . that’s about 4, maybe 5, posts here. I’ll save it for when I might decide to pursue for my amusement a History Masters in my old age retirement. All data was drawn from readily available information that can be found on the internet if one knows where to look. Add knowledge of statistics/statistical practices (already have that masters) and . . . voila, a do it yourself project.

    The USN continued to employ the TBF/TBM through the war because they could carry and deliver torpedoes AND bombs – efficiently. The torpedo plane tragedy at Midway was the direct result poor strike coordination, especially in terms of fighter protection. The lesson to be taken away was that in the face of an alert and numerous CAP, a heavy escort group is an absolute must. But, you have to ask yourself, how many times were those same conditions encountered? Answer: Not many. Bottom line was that by the end of the war, the fighters then in use could do the same job as the dive bombers and the torpedo bomber was dual purpose torpedo delivery and level/glide bombing delivery, handy if you’re planning on poking holes in the side of some monster battleship bent on its own destruction.

    The last time a US carrier plane dropped a torpedo in anger was during the Korean War, the target was the release gates on a dam. That does not mean the capability went away, it means the opportunity to do so went away. It might be cogent to remember that the one of best ways to sink a submarine is with a homing torpedo dropped from an aircraft, a capability which could be exercised tomorrow should the need arise.
     
  13. georgew

    georgew Member

    Some great info on this thread but I'm going to try and approach the question posing as a newly qualified USN pilot in 1941 who is asked Torpedo or dive bomber.

    Torpedo involves a slow lumbering plane carrying a rather large bomb that must be dropped at optimum height at slow speed whilst being shot at by a queue of zeros and also ship guns. Assuming I managed to drop this bomb it may have been damaged by fire and fail to detonate or shatter in the sea anyway. If it hasnt, a ship can still turn away and all my efforts result in a big miss as I shoot by getting shot at again. Scary thought..

    Dive bomber lets me get to a nice big high point where my simple brain lets me use my aircraft as an aiming mechanism and with less mechanical parts that a torpedo I can more or less guarantee my bomb will go off. My speed in a dive will mean less pressure from fighters and give me a chance to escape shipboard fire too.I may be lucky and be able to carry two bombs as opposed to one torpedo so if I miss I can go round again. Prospects look better..

    I saw this quote in one of the posts above

    “Torpedo plane pilots and crews had the most self-sacrificing mission in US naval aviation, not just there but through the entire war.”


    I can agree wholeheartedly. I would have been the man in the Helldiver.
     
  14. R Leonard

    R Leonard Active Member

    Except in 1941 you, as a brand new, shiny gold bars ensign, with a brand new set of wings on your chest, checking the orders list to see which operational training squadron you were going to, would not have known a heck of a lot about Japanese type 00's. Oh, and no one cared in which of the communities you wanted to serve, you went where you were sent . . . many a would-be ace of the base ended up in patrol planes. Not that there's anything wrong with patrol planes, not just a few ended up in high pucker factor situations that called for cool heads and skilled maneuvering, but not every one can be a fighter pilot or a dive bomber pilot.

    The naval aviator quoted was my father, a fighter pilot off USS Yorktown at Midway, and a career naval officer.
     
  15. vashstampede

    vashstampede Active Member

    @ georgew,

    Actually a lot of bombs dropped by dive bombers also did not detonate upon impact. There were quite a lot of cases where the bomb went through the ship dock and down several levels before stop, but did not explode.

    Ships can also maneuver out of the way of bombs from dive bombers, since the bombs were dropped from the sky and it usually take a long time before hitting the sea level.

    Yes, we have all agreed that torpedo bombers had much lower survivability compare to dive bombers due to their speed, altitude, as well as their attack patterns during the attack.
     
  16. R Leonard

    R Leonard Active Member

    A simple matter of fuse settings. For the typical GP bomb, the USN tended the set nose fuses at about 0.00125 seconds and the tail fuse at about 0.1000 seconds. This meant that the nose fuse should set the bomb off at impact. If, for some reason that fuse should fail, the tail fuse will set the bomb off almost a tenth of a second later, long enough for the bomb to penetrate at least one deck, and sometimes more depending on how "hard" is the target.

    Easy to do when those doing the dropping are level bombers at 20,000 feet. The typical dive bombing profile calls for a release between 1500 and 2000 feet. This means that the bomb is only in the air for about 6 seconds. If you are driving a ship being attacked by a 6 plane dive bomber division that means that when the first bomb hits, either you or the water, there are still 5 more bombs in the air headed towards you and they will land in the next 24 seconds. Your maneuver options are pretty limited, though I can think of at least one destroyer that survived an attack by 30 plus dive bomber and the only damage was shrapnel from near hits.

    No, that is your opinion. The percent chance that a given aircraft would be lost on a given action sortie were, for the TBF: 0.07% to enemy aircraft, 0.98% to enemy anti‑aircraft fire, and 0.64% operationally, or 1.69%, overall. For the SB2C percentages were 0.10%, 1.42%, and 1.16%, or 2.68%, overall; for the SBD percentages were 0.71%, 0.66%, and 0.79%, or 2.16%, overall; and for the TBD percentages were 13.74%, 6.04%, and 4.40%, or 24.18%, overall. Thus the relative survivability on a given action sortie, by plane type, can be ranked as TBF, SBD, S2BC, and TBD.

    These numbers and other similar analyses one could make with the easily and readily available operating statistics pretty well dispel any theory that the TBF might be more vulnerable than either the SBD or the SB2C. Only in the case of loss percentages resulting from enemy anti‑aircraft fire does the TBF not come out on top as the most survivable and, even then, it was still almost 45% more survivable than the more predominant (in terms of action sorties) of the two dive bombers, the SB2C. Overall, comparing VT loss percentage per action sortie to VSB loss percentage per action sortie, the VT aircraft (despite the aura of the tragic TBD losses at Midway) come out far and away more survivable than the VSB aircraft. For VT aircraft, losses were (# of losses or percent of action sorties): to enemy aircraft, 52 or 0.14%, to enemy anti‑aircraft fire, 364 or 1.00%, operationally, 239 or 0.66%, and overall, 655 or 1.81%. For VSB aircraft, the same numbers are: 61 or 0.25%, 308 or 1.24%, 266 or 1.07%, and 635 or 2.55%, respectively. This shows that VT aircraft, generally, were slightly less than 41% more survivable overall and enjoyed survivability rates that were 71.0% higher for loss by enemy aircraft, 23.3% higher for anti‑aircraft fire, and 62.3% higher for operational losses when compared to the VSB aircraft losses.

    Regards
     
  17. FMAlanbrooke

    FMAlanbrooke New Member

    The Luftwaffe didn't make much effort in this area but they did have three types of torpedo bombers in 1940, and torpedo bomber versionss of aircraft like the He III after that. Firstly there the He 59, of which 142 were built. It was used as a torpedo bomber in 1939 and as a reconnaissance aircraft in 1940. 18 December 1939 North north-west of rattray Head, the British fishing steamer Active (185 GRT) was sunk by an airborne torpedo launched by an He 59 (Ku.Fl.Gr 3./706).

    Secondly there was the He 115 Floatplane. The only operational airborne torpedo Staffel ready for action In July 1940 was 3/Ku.Fl.Gr 506 based at Stavanger, to be followed by 1./Ku.Fl.Gr 106 from mid August based at Norderney (on the North Sea coast of Germany) – a total of about 30 aircraft. Between August and December 1940, they used about 160 torpedos sinking about eight ships totalling around 60,000 tonnes.

    Thirdly there was the Fieseler Fi 167 of which 12 were operational with an experimental unit in 1940, although built for carrirer use they were used with a coastal naval squadron in 1942.
     
  18. groundhugger

    groundhugger Member

    I think the answer is in the design of the ships you want to sink , most Capital Naval ships had a Torpedo belt of armour around and below the water level , and armoured decks ,to foil torpedo bombers , and armoured decks to hopefully foil the dive bombers , Merchant ships were totally vulnerable to any attack , Luck and skill and High Explosives , and a double shot of 'Heroism' . my respects to those guys crewing those planes on those 'suicide missions' and the guys staring at the bombs coming towards them , it was literally 'horses for courses' which aircraft you chose to attack with and hopefully got lucky !
    Also the memorable missions of obsolete Fairy swordfish biplanes attacking the 'Channel Dash ' Battleships in the English Channel comes to mind , 'Balls of steel ' crikey !
     

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