Dive bombers to Ceylon 1942 (1 Viewer)

[Admiral Beez]

@Shortround6's post #69, and the following conversation he is having with S Steamed_Banana .

Ah, I'd filtered those out as OT. Whenever I see needless digressions or threadjacking I imagine Gold Five as he says, "Stay on target!" to Gold Leader in Star Wars: A New Hope.

 

[yulzari]

Yes the Commonwealth invasion of Madagascar and the following six months of fighting against the French addressed the great hazard posed by a Japanese use of Madagascar even though the risk was moderate that it would happen. The length of the campaign against the French displays both the limited resources given for the campaign and the size of Madagascar. The place is huge (@600,000 sq km) and has some very difficult country.

The Commonwealth forces had some experience fighting the French such as Mers el Kébir, Djibouti, Dakar (lost), Syria, Lebanon, Algeria as well as Madagascar.

Trivial fact: the Germans never bombed Gibraltar but the French did in July 1940 and September 1940 whilst the Italians did some in 1942 and again a couple of times in 1944.

 

[Thumpalumpacus]

I know I get a little detail orientated at times.
In this case the Zuiho was a converted submarine tender and was about the size of an Independence class carrier, except without any left over cruiser armor or the sub-division of the cruiser. As noted a number of time, US bombs were about 50% HE, British GP bombs were 27-31% with the 250lb being 27 and a 1000lb (if you could find one in early 1942) at 31%.

Near misses are iffy. Very close can spring hull plates and cause flooding. The US bombs were more likely to do this given the same distance from the hull or would do the same damage hitting further from the hull than a British bomb of the same weight.
US 1000lb bombs get very dangerous, their HE charge is in the same catagory as an 18" torpedo, a bit bigger than most 18" torpedoes. Trying to aim a little bit off to get a near miss on purpose was foolish.
Not all ships used the same thickness of hull plating (or even the same steel) and not all ships used the same framing or spacing.

Dive bombers were very useful during the early part of the war, things got more difficult as time went on. Using the Zuiho as an example again, at Santa Cruz she had eight 5in guns in four twin mounts. Japanese 5in AA guns fired about 2/3rds as fast as the US 5in (everybodies heavy AA fired slower than the US 5in) and she had eight 25mm guns in four twin mounts.
At some point in 1943 the 25mm count went to 48 guns and at some point in 1944 she got another 20 guns (total 68?) and 6 rocket launchers. The Japanese (French) 25mm was a really crappy gun for a number of reasons but diving on a ship that had 68 of them compared to 8?
British and Americans were adding light AA as fast as the factories could make the guns and mounts all during the war. Diving bombing a 1943 British or American ship could be a terrifying experience. And they didn't stop in 1943.

Unknown to the Allies the Japanese damage control sucked and their handling of gasoline fumes also sucked so their carriers were often lost to damage that was survivable by western carriers.

None of that changes the fact that when you've got big flat wooden decks and lots of fuel and bombs, a single dive-bomber can ruin your day. Ask USS Franklin. 2 250-kg bombs nearly sank the ship, cost almost 800 dead, and most definitely not a Woolworth carrier.

This in 1945. If USN damage control had been 1942-quality, ship's gone, no one cares about VT fuses or the many quad-40s ... because all it takes is one bomb at the wrong time.

 

[Admiral Beez]

None of that changes the fact that when you've got big flat wooden decks and lots of fuel and bombs, a single dive-bomber can ruin your day. Ask USS Franklin. 2 250-kg bombs nearly sank the ship, cost almost 800 dead, and most definitely not a Woolworth carrier.

That's why I think this could have been the greatest day for the Skua and/or Chesapeake. You've got unprotected flattops with unarmored decks filled with aircraft, with crews and processes totally unprepared for damage control. Let's put FAA men in the Skuas, RAF in the Chesapeakes and go at em.

 

[Thumpalumpacus]

That's why I think this could have been the greatest day for the Skua and/or Chesapeake. You've got unprotected flattops with unarmored decks filled with aircraft, with crews and processes totally unprepared for damage control. Let's put FAA men in the Skuas, RAF in the Chesapeakes and go at em.

I think better aircraft would help. A6Ms could and did chew up better DBs in the right circumstances ... but more planes are better than fewer.

 

[Steamed_Banana]

I don't see that as useful for Ceylon. 1) the time for this modification program is probably going to see them late anyway, and 2) even if these modified-into-fighters could be delivered in time, how useful might they be? The Zero has all the cards -- turn, roll, climb, and perhaps top speed (?)

Totally agree, but Fulmars while not great against zeros had some utility as armed recon planes.

Even in their obsolescence they were dangerous airplanes. To be fair, the same could be said of other planes as well. I think the Stuka aged worst, the Val close behind but still useful into 1943. The pathetic fact is that this mishandled SB2C program meant that SBDs flew well into 1944 for the USN, and with the USMC for the duration. I loves me some Dauntlii. Kinda like the B-17, a leftover from an earlier era, but hung tough and still capable, in good hands.

My assessment of the Stuka greatly improved from reading some detailed combat histories from the Med and Russia. I'd definitely say they were still quite dangerous weapons well into 1943, for example at Kasserine pass. Absolutely lethal against the British convoys in the Med as well, where front line fighters were a little more rare.

Stukas were probably the most accurate dive bombers, and required less skilled crew, and had surprisingly good ability to evade fighters. The problem the Stuka had was that the German fighters were not ideal for sustained dogfighting which was kind of necessary to do effective bomber escort. In the Med the Bf 109 pilots would often abandon the Ju 87s which didn't necessarily mean they got slaughtered (sometimes they did, but often they managed to evade) but it did prematurely end their bombing raid. The FW 190 basically is what replaced them (and somewhat, the Ju 88) but the FW 190 wasn't as accurate and once fast enough fighters were around, Ju 88 had appalling losses sometimes.

The SBD was like the Stuka and the D3A, they were all flawed but all lethally effective longer than people assume, and in more roles (SBD and D3A both did fairly effective armed recon and ASW as well). But for sinking warships, those are the big three for WW2, IMO.

(and their replacements were problematic for everyone - D4Y had a host of problems, B6N came too late and not quite enough of a performance edge to matter, Aichi B7 looked great on paper but came even later, and was too big to operate on most IJN carriers. Stuka was never replaced by another dive bomber. Using He 177 in that role was just harebarined. At least the SB2C was eventually tweaked sufficiently to play some role in the war. The biggest flaw with that plane was IMO down to Navy insisting on making it so short so they could fit two on an elevator simultaneously)

I am under the impression that Swordies did carry radar and used it in night and low-vis situations. Albs too. E EwenS made mention of Rob Stuart, whose work I've read over at Combined Fleet. He writes about how Somerville contemplated a night-strike.

Only limit for the Swordies on that one is about a 150-175 mile combat radius with a torpedo (? just guessing there based on max range), though I guess some of the UK patriots around here can fill is in on the precise details.

I know virtually nothing about Wellington maritime operations except for reading about some Med operations. I'd love to hear more.

Wellingtons are another very early design that punched above it's weight for a long time, they were absolutely lethal against Axis shipping in the Med, good at ASW, and I gather scored a few points in the Pacific Theater as well. They were very slow and not really capable of duking it out with fighters in the daytime, but they had almost infinite range and did night time bombing and torpedo attacks, mine laying etc. quite effectively. They did all kinds of weird interesting missions in CBI too. Again hopefully some of the UK patriots can fill us in with more detail if any want to.

But I don't think the IJN had any night fighters per se, or in April 1942 air search radar, so a night torpedo attack might indeed be a nasty surprise for them. I guess the catch would be, for it to be effective you'd probably need a lot of those Wellingtons. PBYs could also be used this way of course.

 

[Steamed_Banana]

I think better aircraft would help. A6Ms could and did chew up better DBs in the right circumstances ... but more planes are better than fewer.

Daylight bombing attack with slow bombers and no fighter escort just isn't going to work against IJN, in my opinion. Maybe fast bombers like Marylands could survive but they are nowhere near as accurate as a DB.

If you wanted like Skuas and Chesapeakes to hit IJN carriers with that fleet of them, they would need a huge fighter escort with at least competitive fighters. Unless maybe they managed to attack the CVL out on it's own or something.

 

[SaparotRob]

That's why I think this could have been the greatest day for the Skua and/or Chesapeake. You've got unprotected flattops with unarmored decks filled with aircraft, with crews and processes totally unprepared for damage control. Let's put FAA men in the Skuas, RAF in the Chesapeakes and go at em.

And Marines in the Wildcats!

 

[EwenS]

Airfields on Ceylon in April 1942
Colombo Racecourse - turned into an airfield in early 1942. Passed to RN in 1943

Colombo Racecourse

Ratmalana - previously Colombo Civil Airport with some use by the FAA in 1941 before being taken over by RAF in March 1942.

China Bay, Trincomalee - pre-war RAF station to support the RN. Significantly upgraded with longer runway during WW2 to handle B-29s. To RN late 1944.

Trincomalee

Koggala Lake - flying boat base at southern tip of the island.

Additions during WW2 after April 1942:-
A large construction programme was begun from mid-1942 to create new airfields to support both RAF operations out over the Bay of Bengal as well as RN second line squadrons and shore bases for carrier groups when in port as well as defence of the island. Some of these are only very rarely heard of.

Vavuniya - work begun 1942. Opened by early 1943 for the two TB squadrons.

Vavuniya

Negombo (Katunayake) - built 1944 as a Very Heavy Bomber station (i.e. for B-29) but used as a transport Staging Post. Became more important post war.

Kankasenturai - was a Liberator GR base by 1944.

Minneriya - work started on construction July 1942. Another Liberator GR base by 1944
Minnerriya

Dambulla - land requisitioned for an Advanced Landing Ground. Fighter station available by late 1942.

Sigiriya (near Kandy) - land requisitioned in 1942. Became Mountbatten's "private airport" from late 1943 according to one report.

Katukurunda - opened in 1942, and to RN

Katukurunda

Puttulam - Originally planned as a dispersal field for RAF units around Colombo but opened Nov 1942 for RN

Puttalam

Kalemetiya - created as a fighter station by Aug 1942.

Mawathagama - grass strip near Mountbatten's HQ. Suitable for up to C-47.

 

[Steamed_Banana]

And Marines in the Wildcats!

Short range with bombs. plus the Marines would beat up all the Britishers in Ceylon and this would dampen morale.

 

[SaparotRob]

I really don't think these things through.

 

[Thumpalumpacus]

Daylight bombing attack with slow bombers and no fighter escort just isn't going to work against IJN, in my opinion. Maybe fast bombers like Marylands could survive but they are nowhere near as accurate as a DB.

If you wanted like Skuas and Chesapeakes to hit IJN carriers with that fleet of them, they would need a huge fighter escort with at least competitive fighters. Unless maybe they managed to attack the CVL out on it's own or something.

Or they'd have to have the numbers to distort and distend the CAP ... and still be willing to take heavy losses, a la Americans at Midway, where our fighter escorts were essentially ineffective due to small numbers and large miscommunications.

 

[Thumpalumpacus]

And Marines in the Wildcats!

And Gabby Gabreski on bass guitar!

 

[RCAFson]

Good discussion so far, but we have to remember that the IJN carrier TFs had no AW radars in April 1942, or in May or June 1942 and consequently IJN CAP failed to intercept RAF/USN strike missions before the bombs were dropped on several occasions, including April 9 1942.

 

[Steamed_Banana]

Or they'd have to have the numbers to distort and distend the CAP ... and still be willing to take heavy losses, a la Americans at Midway, where our fighter escorts were essentially ineffective due to small numbers and large miscommunications.

Having a strong fighter force back at Ceylon would be helpful, because it would attrit the IJN air forces as they will probably be forced to attack and try to neutralize it.

IJN has a range advantage for daylight fighters available to Allies in April 1942, so they can decide if they want to come within range of daylight Allied bombing strikes, but on the other hand if they want to wreck the airfields in Ceylon, or get at Royal Navy ships docked their or lurking nearby, they will have to fight their way through the RAF / FAA CAP and take losses accordingly if the latter is robust enough.

 

[Thumpalumpacus]

IJN has a range advantage for daylight fighters available to Allies in April 1942, so they can decide if they want to come within range of daylight Allied bombing strikes, but on the other hand if they want to wreck the airfields in Ceylon, or get at Royal Navy ships docked their or lurking nearby, they will have to fight their way through the RAF / FAA CAP and take losses accordingly if the latter is robust enough.

IJN attack aircraft had good range as well. I suspect there might be a sweet-spot where KdB could strike Ceylon without much danger from the single-engined Allied bombers. I doubt Nagumo/Genda et all crunched those numbers in this specific case.

D3Ys could, however, reach Guadalcanal from Rabaul (550 miles or so). Adjusting for Op C, with the uncertainty of carrier ops, hypothetically reduce that to 400 miles. Do the Allies have dive-bombers that can reach that far -- or fighters to escort them? I don't believe so.

 

[Steamed_Banana]

IJN attack aircraft had good range as well. I suspect there might be a sweet-spot where KdB could strike Ceylon without much danger from the single-engined Allied bombers. I doubt Nagumo/Genda et all crunched those numbers in this specific case.

Oh, 100%, and I bet they did crunch the numbers, albeit probably with some partly flawed intel

D3Ys could, however, reach Guadalcanal from Rabaul (550 miles or so). Adjusting for Op C, with the uncertainty of carrier ops, hypothetically reduce that to 400 miles. Do the Allies have dive-bombers that can reach that far -- or fighters to escort them? I don't believe so.

No they do not. But they do have some level bombers that can probably reach. The problem is without fighters, with multiple IJN carriers out there, RAF or FAA bombers in the daytime are going to be hard pressed to survive, IMO.

 

[Admiral Beez]

Good discussion so far, but we have to remember that the IJN carrier TFs had no AW radars in April 1942, or in May or June 1942 and consequently IJN CAP failed to intercept RAF/USN strike missions before the bombs were dropped on several occasions, including April 9 1942.

Indeed. If there was on thing the Japanese should have acquired from their German allies it's radar tech. Imagine at Coral Sea and Midway (first tested and then perfected after this Ceylon raid) if Nagumo's carriers had air-intercept (air-warning) radar. By 1939, the Germans had installed surface-search and gunnery radars, not air-intercept onto the Scharnhorst class battleships, which could have been installed as an air-warning set in at least one IJN carrier (along with a CIC or FDO and working radios) by 1942. If Nagumo has radar, my Skuas and Chesapeakes, along with the Blenheims will not find those essential undefended skies that day.

 

[RCAFson]

Oh, 100%, and I bet they did crunch the numbers, albeit probably with some partly flawed intel



No they do not. But they do have some level bombers that can probably reach. The problem is without fighters, with multiple IJN carriers out there, RAF or FAA bombers in the daytime are going to be hard pressed to survive, IMO.

On April 9 1942 9 Blenheims bombed the KB, and four were shot down by CAP, near the carriers, for the loss of one Zero, but unluckily the Blenheims were intercepted a 2nd time by Zeros and Vals returning from the Hermes strike, and another Blenheim and a Zero were shot down. So the KB, with 5 carriers and ~20 Zeros aloft only managed to shoot down 4 Blenheims. If we add ~30 Fairey Battles to the Blenheim formation, it seems unlikely that RAF losses would increase much since the Battle has the same (IIRC) defensive armament as a Blenheim and similar top speed. Ditto for a squadron or two of Skuas, albeit slower than Blenheims.

 

[Thumpalumpacus]

D3Ys [sic; should be "D3A"] could, however, reach Guadalcanal from Rabaul (550 miles or so).

To clarify, I looked back into my bookshelves and found that I misremembered this. The Type 99s that struck the 'Canal sortied from Buin and not Rabaul -- a much shorter flight.