Thank you, this was exactly what I was looking for. I knew US torpedoes were crap, thus many didn't go off, but the OTHER main issue early in the war was the sheer number of plain misses. Which kinda stunned me.Aerial torpedo training early in the war didn't explicitly include the fast mental footwork needed to calculate by how much, during the time between your drop (or when you're spotted, if that differs) and when the torpedo and present target paths converge, the target might be able to be at a different location as of that intended convergence time than where you expect them to be; and how short you need to make that time-between-drop-and-convergence (i.e. how close to the intended convergence point, but of course always farther away than the minimum depth-stabilization-and-fuze-arming run distance) so that the target is hit even if they maximally change their course and/or speed.
You also evaluate where you are, and the water depth. All aerial and surface-fired torpedoes usually dived to a considerable depth, then rose to their set depth. That might take multiple hundreds of yards. A torpedo dropped in too-shallow water would hit the bottom and be thrown off course, or damaged, or just stick in the bottom and be lost. A torpedo dropped too close to the target likely would run under it, because it wouldn't have risen to set depth yet.
This illustration shows an attack by a motor torpedo boat, but exactly the same techniques were used by torpedo planes. You estimate the target's speed, you know what your minimum run is (which depends partly on the sea state), you know what run depth and speed your torpedo(es) are set for, and you judge how much defensive fire there is already or is about to begin in regard to how close you can get before releasing your (first, if multiple) fish. Given those parameters and the angle between your attack course and the target's present course, you do a mental calculation of the offset angle that defines your firing point, and you continually measure (or mentally judge, but measurement is more accurate) that angle as you rapidly close on your drop point.
If you have time and knowledge, you identify the target ship and mentally recall its propulsion capabilities and rudder authority, and calculate whether your attack will be defeatable if the captain / helm is maximally aware and the engine room and rudder crews are sharp.
What the target should do upon seeing that a torpedo attack is coming is change its speed and course. Almost all ships slow down much more readily than speed up, so what most ships should do is command their engine room to do an all stop and then emergency astern, plus a rudder command for full rudder to turn toward you (because a turn toward the incoming torpedo is more likely to cause a miss than a turn away).
(The reason why torpedo bombers and MTBs usually didn't try attacking destroyers is because destroyers' tactical radius...their tightest turn...is likely to be shorter than your torpedo's minimum arming and stabilization distance. So, if they were paying attention and not stopped or for some reason at very slow speed, you couldn't possibly hit them because they easily could be nowhere near your intended convergence point.)
Malaya What If
- Thread starter Fatboy Coxy
- Start date
Monthly BUAER Reports are not at NHHC - they should be! They're big files, 70-100 pages that were sent to me. With the Asiatic Fleet's challenges and considering that these were prepared at the Navy Department in Washington, December 31 numbers would be based on latest reports received, and therefore, are probably slightly off. FAW-10 (successor to PATWING-10) War History is here: https://catalog.archives.gov/id/77519727. Some NARA files that I've had declassified are also extremely large. I was able to post the weekly operation summaries for AIRLANT/PATWINGSLANT from 4 Dec 41 to the end of Jan 42 here: http://www.ww2f.com/threads/uss-wasps-aircraft.76433/#post-890078 which bridges the gap to the NHHC reports. The War Diaries for the Pacific are much better than those for the Atlantic, and the PHA and Grey Book are gold, so we have better numbers for PACFLT.
Unlike the archives available online from the UK, availability here remains a little weak.
Thanks for finding the aerial torpedos and locations. I dried NHHC but get a msg that they are moving to a new server
Doesn't reflect all PBY losses either, only those Dec 8. Should be down 6 instead of just 2 due to the loss of 4 after Christmas. War Diary should also list operational losses too. I'll see about digging them up.
Torpedo aiming skills are a lot like shotgunning birds. You have to know how to lead, and you have to choose targets at close enough range that your shot pattern will still get them even if they change course. Those are skills that you develop by experience, which means practice and more practice, plus doing it in combat when the pressure's on. Someone with mostly classroom knowledge of torpedo attacking, and maybe one or two training drops under ideal conditions with no real pressure, isn't going to be good at it.
On Guadalcanal, the Japs didn't have a lot of cannon and mortar ammo, but they did have grenades. So, they fired lots of rifle grenades and/or threw hand grenades on high arcs toward the Marine fighting holes. The Marines could see these coming, but quickly figured out that no one could hit and deflect them with rifle rounds. Some of their soldiers though said they could do it with shotguns. So, the commanders had some flown in. But, most Marines weren't good at it. The effective few were the ones who grew up around shotguns and bird-hunting...ducks, quail, pheasants...and had that experience-gained ability to judge trajectory, pick their range and lead by the right amount.
Of course, no one grows up firing torpedoes in combat, but the same principle applies. You learn to do it by being alongside someone else who does it successfully, then by doing it many times yourself... not by sitting in a classroom.
Submarine commanders got to "apprentice" as junior officers, so had a chance to learn some of what was needed on-the-job. Torpedo bomber pilots mostly learned from classroom training and a small number of practice drops. They weren't very likely to learn on-the-job because the survival rate was so low.
Is there some way that the ability of a Swordfish to perform an Immelmann after a torpedo drop can be worked into this?
Errolwi
Monthly Donor
We have Vildebeests (quickly decided that they were only usable at night), not Swordfish. But take a look!
www.pond5.com
The RNZAF had a pre-war display team.
New bombers for New Zealand | Stock Video | Pond5
Get this stock video and more royalty-free footage. New bombers for New Zealand. ✔️Best Price Guaranteed ✔️Simple licensing. Download Now ➡️
www.pond5.com
The RNZAF had a pre-war display team.
Errolwi
Monthly Donor
Some explanation in this scanned wartime booklet(?). Neat forum discussion on Vildebeest, Swordfish, dive-bombing etc too. Dave H and James (JDK) are mates of mine, and top blokes.
Vildebeest versus Swordfish
I have been summing up a bit of a comparison between the Vickers Vildebeest/Vincent family and the Fairey Sworfish. The two aircraft look somewhat similar, especially the Vildebeest Mk IV which had a cowled engine and three-bladed propellor. Both had the Bristol Pegasus engine of similar marks...
Fatboy Coxy
Monthly Donor
Hi Anteos, thank you for your kind words, and welcome, please feel free to post, whether it be fact, question, or adding to off target chat we indulge in as we meander through this story.
Fatboy Coxy
Monthly Donor
Hi Butch, at first it sounds a lot, but 20,000 pounds is only about 60 depth charges, which is what my money would be on
Hi Errolwi, the British were desperately short of long range maritime aircraft, I think they only had five of these aircraft in Singapore, provided by the Dutch. The British had aircrew, and a lack of planes, and the Dutch had considerably more American built aircraft arriving than they could initially manage. I agree with you, though they might be able to fly these aircraft, I think any success in conducting a torpedo attack would be down to luck, and I suspect a depth charge attack would need a large slice too. Given time they could learn, but there's no time for that now.
Fatboy Coxy
Monthly Donor
Hi Butch, Yes there are some ASV radar sets for the handful of Albacores based in Singapore, see https://www.alternatehistory.com/forum/threads/malaya-what-if.521982/post-23790690, and https://www.alternatehistory.com/forum/threads/malaya-what-if.521982/post-23873624, but installing them was problematic. Strangely the Fleet Air Arm was able to get them working in the Swordfish well before the Albacore, although they tried the Albacore first. In this timeline, recognising that the FAA had the capability of ASV aircraft by early 1941, I will twist the historical line, overcoming the technical challenges to installing the ASV Mk II into the Albacore earlier, which will provide this backwater of the war with a very small number of easily identifiable ASV aircraft. But don't expect miracles from them.
Fatboy Coxy
Monthly Donor
Hi JWilly48519, totally agree, however...
We have two competing services for these ASV's, the RAF, who's Coastal Command was using them in the Atlantic, and the FAA of the Royal Navy. The few Catalina's that RAF 205 squadron have recently acquired are not fitted with ASV. The Lockheed Hudson, of RAAF 1 and RAAF 8 Sqn's is used in a maritime recon/bomber role but to my knowledge hadn't been fitted with them. The British manufacture of these radar sets was small and slow, but they had given one to the Americans as part of the Tizard Mission, and by 1942 the Americans were turning out hundreds, soon to move into thousands of them. Whether the Hudson's got them later I don't know, the Hudson's were used extensively in Martine Recon role around New Guinea and the Solomon Islands in 1942-43.
Now as a side note, but certainly of interest to this story, the Supermarine Walrus's carried by both HMS Prince of Wales and HMS Repulse, are equipped with the ASV Mk II, as they were historically!
Fatboy Coxy
Monthly Donor
Hi Errolwi, thank you for this, an interesting read.Some explanation in this scanned wartime booklet(?). Neat forum discussion on Vildebeest, Swordfish, dive-bombing etc too. Dave H and James (JDK) are mates of mine, and top blokes.
Vildebeest versus Swordfish
I have been summing up a bit of a comparison between the Vickers Vildebeest/Vincent family and the Fairey Sworfish. The two aircraft look somewhat similar, especially the Vildebeest Mk IV which had a cowled engine and three-bladed propellor. Both had the Bristol Pegasus engine of similar marks...www.key.aero
Fatboy Coxy
Monthly Donor
Hi Ihagambia, well said, and I need to keep that in mind as I go off killing thousands.
Fatboy Coxy
Monthly Donor
Hi USNA91, I don't think I've seen you here before, wow, thank you for this, fascinating stuff.
Fatboy Coxy
Monthly Donor
Hi Edgeworthy, have a look at the Immelmann Turn, https://en.wikipedia.org/wiki/Immelmann_turn, I suspect the high climb to pre stall and half roll would offer up the aircraft as a splendid target for AA fire. Remember in the torpedo attack run in, the aircraft is already facing at an angle off the bow of the ship, the pilot simply turns further away from the ship to get away. But I think for any pilot making a torpedo attack against a warship, its brown trouser day!
That said, a torpedo attack is an exciting theme, and we're gonna have a few of them!
Fatboy Coxy
Monthly Donor
Ah, so after that little flurry, you've probably noticed I've returned, having to accept I can't research everything down to the last detail, I'll never get the story written. Next story instalment coming tomorrow (that's Monday for me).
First I've ever heard of using shotguns to deflect or harmlessly detonate incoming grenades, and on Guadalcanal against the Japanese at that. Is this for real?
They did train for it and it was first attested in WW1, however it does not seem to be very high chance. From Youtube