Set a Ceylon trap for Nagumo, March 1942

[The Basket]

You refer to Galipoli as a disaster, but not the loss of Malaya and Singapore. Your criteria for disaster labeling makes no sense. I had a longer rebuttal drafted but there's no point, and we'd be threadjacking the thread off topic. Back to Ceylon I go.....

Yeah and I wouldn't have bothered reading it so there that too.

 

[Admiral Beez]

Do we know what Nagumo's plan was for venturing into the Indian Ocean? Did he know there was a British carrier force to attack? If the goal was just to harass any transports or small British bases in the region then sailing much of your Empire's essential capital ships to within easy reach of Ceylon-based naval and air power seems a massive risk. Of course we could argue the risk paid off since Nagumo's fleet made it home again, but save for an old carrier and some cruisers Sommerville's force remained untouched. Once he was made aware that the British eastern fleet remain intact, how can Nagumo consider his mission anything other than a failure?

The risk to Nagumo does not seem worthwhile. Had the British attacked with what they had (rather than what I'm suggesting they could get) Nagumo could have have lost a carrier or two, significantly impacting IJN preparations for the coming Coral Sea and Midway operations. Nagumo should have been at home, preparing his fleet. I wonder if he was jealous that the army was getting all the glory at Malaya and DEI and wanted to venture out - but he's got the laurels of Pearl Harbour to sustain any ego I would think. That said, until now only Rear Admiral Takagi at Java Sea has given the IJN much of anything to do in 1942, beyond troop transportation.

 

[SaparotRob]

You refer to Galipoli as a disaster, but not the loss of Malaya and Singapore. Your criteria for disaster labeling makes no sense. I had a longer rebuttal drafted but there's no point, and we'd be threadjacking the thread off topic. Back to Ceylon I go.....

How good were HM forces at cooperation and coordination? IJN was the master of coordinated air strikes. However, the IJN and IJA would rather commit hari kiri then work together. The USN was still at the "okay that didn't work, let's try this" stage.
It looks like HM forces had the personnel and equipment but could they tie all that together?
I've read on this Forum how the Buffaloes and Hurricanes would have done better with early warnings and better communication. Just wasn't there. It just seems a bit of a reach at that point in time. Late '44, they would have the skills and experience to pull it off.

 

[RCAFson]

Do we know what Nagumo's plan was for venturing into the Indian Ocean? Did he know there was a British carrier force to attack? If the goal was just to harass any transports or small British bases in the region then sailing much of your Empire's essential capital ships to within easy reach of Ceylon-based naval and air power seems a massive risk. Of course we could argue the risk paid off since Nagumo's fleet made it home again, but save for an old carrier and some cruisers Sommerville's force remained untouched. Once he was made aware that the British eastern fleet remain intact, how can Nagumo consider his mission anything other than a failure?

The risk to Nagumo does not seem worthwhile. Had the British attacked with what they had (rather than what I'm suggesting they could get) Nagumo could have have lost a carrier or two, significantly impacting IJN preparations for the coming Coral Sea and Midway operations. Nagumo should have been at home, preparing his fleet. I wonder if he was jealous that the army was getting all the glory at Malaya and DEI and wanted to venture out - but he's got the laurels of Pearl Harbour to sustain any ego I would think. That said, until now only Rear Admiral Takagi at Java Sea has given the IJN much of anything to do in 1942, beyond troop transportation.

Nagumo's mission was to hit Ceylon and attack any intervening RN ships (hopefully the BEF), and so cover the raid into the Bay of Bengal, which was designed to aid the IJA invasion of Burma.

 

[Freebird]

Do we know what Nagumo's plan was for venturing into the Indian Ocean? Did he know there was a British carrier force to attack? .

Yes.
On the 9th Japanese were specifically looking for the RN carriers, and upon finding Trincomalee empty of RN capital ships they sent scouts back to Colombo to look for them.
The Japanese carrier CAP shot down an Albacore scouting over the IJN fleet on the 5th, so they knew that RN carriers were in the vicinity

 

[Admiral Beez]

How good were HM forces at cooperation and coordination?

Not good at all, as shown at the Feb 1942 Channel dash where the RAF and FAA completely failed to coordinate their strikes on Scharnhorst, Gneisenau, et al. One of the biggest fails of combined RAF/FAA ops.

So, my thinking is the RAF and RN operate separately at Ceylon. They both know from wire intercepts and intelligence that Nagumo is coming at the end of March or early April. My suggestion is that once the Kido Butai's location is confirmed, the RAF strikes first and hard, no penny packet raids, but one big fist. Then the RN and FAA can approach from the south and do their own attack.

 

[Admiral Beez]

We're Boston's and Maryland's used in low-altitude precision level bombing in this timeframe? They were available in Egypt. Very dangerous to attack carriers in daylight with them as they would be unescorted, but also large payload and good range. Potentially lethal to a carrier even if attrition to the attackers is very high. But I don't know if they were quite suitable, or had the tactics necessary developed for them. But a crash-course on ship sinking could be endeavoured maybe?

It's now end of Feb 1942 the British receive intel that a major IJN move into the Indian Ocean is planned at the end of March or early April. So now we need to assemble and prepare the RAF strike and get it and the necessary bombs, torpedoes, fuel, spares, etc. to Ceylon within the next two to three weeks in order to have time to prepare and gain familiarity with each other, train against RN targets, work with newly set up radar early warning and Catalina long range recon, etc.

Here's what's already there (or in place by end of March 1942). Easter Sunday Raid - Wikipedia

No. 222 Group RAF
No. 11 Squadron RAF (Bristol Blenheims) (Colombo Racecourse)
No. 30 Squadron RAF (Hawker Hurricanes) (RAF Ratmalana, Colombo)
No. 258 Squadron RAF (Hawker Hurricanes) (Colombo Racecourse)
No. 261 Squadron RAF (Hawker Hurricanes) (China Bay, Trincomalee)
No. 273 Squadron RAF (Fairey Fulmars) (China Bay)
No. 202 Squadron RAF (PBY Catalina one aircraft)
No. 204 Squadron RAF (PBY Catalinas)
No. 205 Squadron RAF (one PBY Catalina aircraft)
No. 321 Squadron RAF (PBY Catalinas) (Dutch unit under formation at China Bay)
No. 413 Squadron RCAF (PBY Catalinas)

Not great, with only one squadron of strike aircraft (Blenheims), plus one of bomb-retrofit capable Fulmars (I didn't know the RAF operated Fulmars). We need a lot more than this. The Royal Navy's Force Z, which unlike Nagumo's force was much smaller and without air cover, was successfully attacked by 85 bombers (34 torpedo/51 level) divided into three waves. Nagumo's southern force has 5 carriers, 4 battleships, 7 cruisers, 19 destroyers and 350 aircraft. The RAF focus is of course the five Japanese carriers. Advantages to the RAF are no IJN radar, Nagumo's neglect of aerial reconnaissance and ineffective IJN antiaircraft fire.

IMO, the RAF needs at least ten squadrons (120 aircraft + spares) of torpedo strike aircraft, six squadrons (72 aircraft + spares) of dive or low level bombers and five additional squadrons (60 aircraft + spares) of single-seat fighters.

The best means of getting the short range aircraft to Ceylon in a hurry is by carrier ferry, so in early March 1942 when Sommerville's newly formed Eastern Fleet sails to Ceylon from Home and Med waters the decks of Illustrious, Formidable and Indomitable need to be loaded with RAF fighters.

The multi-engine aircraft will need to be flown in from the UK via Africa and India to Celyon. Bristol Beauforts were also made in Australia, with first production aircraft entering service in August 1941, but Australia to Celyon is not any closer, and without Malaya there's no where to get gas enroute. So, here's the flight plan for our 130-odd Beauforts, Hampdens and whatever multiengine low level or moderately dive capable bombers (Bostons, Blenheims, Marylands, Hudsons, Wellingtons, etc), are available, requiring ferry ranges of up to 1,900 miles. Fuel and spares will need to be prepared for in advance enroute.

1. 1,000 miles Cornwall ,UK around neutral Spain to Gibraltar
2. 1,870 miles to Mallam Aminu Kano in Nigeria (was used interwar for passenger flights and as a ferry base during WW2)
3. 1,140 miles to Sudan
4. 1,325 miles to RAF Aden
5. 975 miles to RAF Oman
6. 1,100 miles to RAF Bombay
7. 920 miles to Trincomalee, Ceylon

See the complete map here, Great Circle Mapper We're not stopping in Lisbon, I just added that to push us as far west as possible around the Iberian Peninsula.

Total flight distance is 8,330 miles. The Hampden's cruise speed is 206 mph, while the Beaufort's is 255 mph. If everyone does the equivalent ground speed of 190 mph this will require 44 hours of flight time. The move will encompass several batches of aircraft so as not to exhaust logistics enroute or provoke too much interest from local spies, with each group taking about a week make the 8,330 mile trip. Assuming maintenance was up to date this should leave their Bristol radials with sufficient TBO (time before overhaul) to begin training and preparation.

 

[gjs238]

Yeah and I wouldn't have bothered reading it so there that too.

Not even a peek with one eye?

 

[glennasher]

Do the RN destroyers have radar yet? I'd think a nighttime torpedo attack on the IJN carriers would do a good job, as the Japanese did so often in the Solomons.

I don't know how good UK sigint was in the Indian Ocean, but getting RN submarines where they can attack Nagumo's force would be first, followed by night air-launched torpedo attacks. If the Nagumo keeps approaching, continue submarine and night air attacks. If they get close enough for RAF fighters to escort attack aircraft, try day attacks, with dive bombers preferentially attacking carriers. After dark, let the destroyer flotillas loose.

 

[Glider]

Some rather obvious problems with this

IMO, the RAF needs at least ten squadrons (120 aircraft + spares) of torpedo strike aircraft, six squadrons (72 aircraft + spares) of dive or low level bombers and five additional squadrons (60 aircraft + spares) of single-seat fighters.

I doubt that the whole of the RAF didn't have ten squadrons of torpedo strike aircraft. They definitely didn't have six squadrons of dive bombers. Low level bombers would have been Blenheim's which were suffering huge losses in anti shipping strike missions in the North Sea and there is reason to believe losses against the IJN would be any less. The fighters could have been scraped together if the UK would release some of the Spit V fighters that were not doing much on the Channel Raids.

Do not underestimate the IJN 25mm AA guns they were not as bad as people paint them.

 

[Kevin J]

Some rather obvious problems with this


I doubt that the whole of the RAF didn't have ten squadrons of torpedo strike aircraft. They definitely didn't have six squadrons of dive bombers. Low level bombers would have been Blenheim's which were suffering huge losses in anti shipping strike missions in the North Sea and there is reason to believe losses against the IJN would be any less. The fighters could have been scraped together if the UK would release some of the Spit V fighters that were not doing much on the Channel Raids.

Do not underestimate the IJN 25mm AA guns they were not as bad as people paint them.

I'd disagree with you, the RAF could have had sufficient torpedo dive bombers and could have had sufficient long range fighters to escort them. The HP Hampden could both dive bomb and torpedo drop. The Miles M. 20 with drop tanks could have escorted them if it had been built. The Fairey Battle was available in both South Africa (340) and Australia (366). It too could dive bomb.

 

[The Basket]

Not even a peek with one eye?

One doesn't. The 25mm was a poor choice especially as the main event. But it did give the IJN gunners something to do while they were under air attack.

 

[Admiral Beez]

I doubt that the whole of the RAF didn't have ten squadrons of torpedo strike aircraft.

With production beginning in 1938, Britain produced 1,180 Bristol Beaufort Mk.I. I don't know how many were produced by Feb 1942, but I would have thought by 1942 Bristol would have changed over to the Mk.II. The RAF's second torpedo bomber, the Hanley-Page Hampden was produced from 1936 to 1941, with 1,430 built. Ceylon needs ten squadrons, or 120 aircraft plus spares. This doesn't seem a huge stretch given the number of aircraft produced to Feb 1942.

I suggest these three active Canadian torpedo squadrons join up with No. 413 Squadron RCAF (PBY Catalinas) already at Ceylon.

They definitely didn't have six squadrons of dive bombers. Low level bombers would have been Blenheim's which were suffering huge losses in anti shipping strike missions in the North Sea and there is reason to believe losses against the IJN would be any less.

The RAF doesn't have any dive bombers whatsoever, but I want anything that can shallow dive with any accuracy. I agree it's likely going to be Blenheims, along with Bostons, Battles and Hudsons. They'll have to depend on fighter cover to make it to their targets. The FAA has just withdrawn its Skuas and they have France's Vought Chesapeakes - maybe send those for this final mission, operating the latter from land in a lightened state.

Considering that IJN carriers seem to be vulnerable to single bomb hits, perhaps 500 lb bombs slung under Fulmars and Hurricanes (Hurribombers were thus armed in 1941) will suffice and the Blenheim, etc can stay home. Making the RAF's part a Beaufort and Hurricane event makes it easier for the RAF.

If just a few of these get through to Nagumo's matchstick flattops and it's inferno time.

 

[pinsog]

With production beginning in 1938, Britain produced 1,180 Bristol Beaufort Mk.I. I don't know how many were produced by Feb 1942, but I would have thought by 1942 Bristol would have changed over to the Mk.II. The RAF's second torpedo bomber, the Hanley-Page Hampden was produced from 1936 to 1941, with 1,430 built. Ceylon needs ten squadrons, or 120 aircraft plus spares. This doesn't seem a huge stretch given the number of aircraft produced to Feb 1942.

I suggest these three active Canadian torpedo squadrons join up with No. 413 Squadron RCAF (PBY Catalinas) already at Ceylon. The RAF doesn't have any dive bombers whatsoever, but I want anything that can shallow dive with any accuracy. I agree it's likely going to be Blenheims, along with Bostons, Battles and Hudsons. They'll have to depend on fighter cover to make it to their targets. The FAA has just withdrawn its Skuas and they have France's Vought Chesapeakes - maybe send those for this final mission, operating the latter from land in a lightened state.

Considering that IJN carriers seem to be vulnerable to single bomb hits, perhaps 500 lb bombs slung under Fulmars and Hurricanes (Hurribombers were thus armed in 1941) will suffice and the Blenheim, etc can stay home. Making the RAF's part a Beaufort and Hurricane event makes it easier for the RAF.

If just a few of these get through to Nagumo's matchstick flattops and it's inferno time.

View attachment 585346

Japanese carriers were vulnerable at Midway because they had a fully armed and fueled strike below decks leading to uncontrollable fires. Shokaku was hit by 3 1000 pound bombs but her hangers were empty so there was no catastrophic fire.

 

[Admiral Beez]

Japanese carriers were vulnerable at Midway because they had a fully armed and fueled strike below decks leading to uncontrollable fires. Shokaku was hit by 3 1000 pound bombs but her hangers were empty so there was no catastrophic fire.

True. If operating within a hundred miles of Ceylon I have to think there would be ready aircraft fueled and armed in the hangars or on deck. But it doesn't take an avgas explosion to mission kill an IJN, or any non-AFD carrier, a few bomb hits should suffice this far from home. If we can get the Hurricanes, can we train their pilots in accurate bombing in time?

 

[SaparotRob]

The Shokaku might not have had a catastrophic fire but it was unavailable for months. It was out of the fight. It might have tipped the balance in the IJN's favor at Midway.
Had this sequence of "what if" events occurred, I'm sure Admiral Somerville would have happily taken it.

 

[Admiral Beez]

The Shokaku might not have had a catastrophic fire but it was unavailable for months. It was out of the fight. It might have tipped the balance in the IJN's favor at Midway.

It was a rather risky move on Japan's to send five carriers into the Indian Ocean so close to Ceylon on the assumption that the island was poorly defended. The ROI just wasn't there, putting more than half of the Kido Butai's carriers at risk to sink old Hermes, a couple of cruisers and some lighter ships. The Japanese seem to have a habit of attacking enemy bases with the goal of hitting enemy fleet carriers - but like at Pearl Harbour and now Ceylon, the carriers are never where they're intended to be.

That they tried again in 1944, this time with a pitiful sized force suggests Japan thought the Indian Ocean was rich with soft targets. Too bad HMS Hermes and the cruisers HMS Dorsetshire and Cornwall weren't still alive to avenge 1942, now that would have been a fun fight to study.

 

[SaparotRob]

It was a rather risky move on Japan's to send five carriers into the Indian Ocean so close to Ceylon on the assumption that the island was poorly defended. The ROI just wasn't there, putting more than half of the Kido Butai's carriers at risk to sink old Hermes, a couple of cruisers and some lighter ships.

That they tried again in 1944, this time with a pitiful sized force suggests they thought the Indian Ocean was rich with soft targets. Too bad HMS Hermes and the cruisers HMS Dorsetshire and Cornwall weren't still alive to avenge 1942, now that would have been a fun fight to study.

I guess that's the same reason why the battle of the Surigao Strait has been a compelling subject for me.

 

[Admiral Beez]

I doubt that the whole of the RAF didn't have ten squadrons of torpedo strike aircraft. They definitely didn't have six squadrons of dive bombers. Low level bombers would have been Blenheim's which were suffering huge losses in anti shipping strike missions in the North Sea and there is reason to believe losses against the IJN would be any less. The fighters could have been scraped together if the UK would release some of the Spit V fighters that were not doing much on the Channel Raids.

It's 79 years ago this week that Nagumo completed his Indian Ocean raid. The anniversary has got me thinking of this topic once more.

Given what was available, and the intel that Nagumo was coming with a strike force of some size, what's the best trap the Brits can set?

 

[Thumpalumpacus]

It's 79 years ago this week that Nagumo completed his Indian Ocean raid. The anniversary has got me thinking of this topic once more.

Given what was available, and the intel that Nagumo was coming with a strike force of some size, what's the best trap the Brits can set?

Having read this thread a while back, and digesting other info I've picked up since joining here, I think if the Brits can muster the airpower it might be doable. But boy, that routing for the UK-based planes across Africa is going to be mighty hard on airframes and engines. Dusty fields, some maintenance infrastructure, but enough to take care of those planes?

The other really big qualm I'd have is disconnecting the RAF and RN strikes, as you suggested upthread. That could well give KdB the opportunity to defeat the attacks in detail, just as they did the Midway-based strikes before the SBDs finally arrived to save the day in that battle. And without an able dive-bomber available in numbers, the Brits would have some hard sledding.

Somerville showed that he wasn't averse to risk, which is usually a good thing in a commander. In fact, I think he played "calculated risk" very well with what he had in OTL, and had he had more resources, could have made a go of it. A night torpedo-bombing attack from the Albacores might could work.

I don't like the idea of a night destroyer-torpedo attack, given the Japanese skill at night-fighting their ships. You risk stripping your fleet of some vital escort.

I really think if your proposal is to come off, the RAF and RN must co-ordinate so that the attacks come in close together and truly tax the defensive capabilities of KdB. I'd try to time it for early morning, so that Japanese CAP is just launching, carriers are silhouetted against the sunrise for the torpedo-bombers, and hopefully the glide- or level-bombers have enough light to work with.