Somerville against the Rising Sun...

[RF]

Oddly, given their vastly superior numbers and supposed superior range, the IJN search aircraft never did find Somerville's main body.

Not that odd, as the Japanese mission was a diversionary raid into the Indian Ocean only, not a pursuit of the RN back into the South Atlantic. The Japanese were operating at the limit of their supply logistics.

[RF]

If Somerville had struck the IJN at night, he would have had many hours to withdraw out of range, especially since there is a high probability that one or more IJN CVs would be crippled, especially in the early evening hours of April 05.

There are two key suppositions here - and I am not convinced by either of them.

One that there would be severe damage to the Jap carriers. Two that the Japs wouldn't immediately be after him.

The line of argument in these assumptions would be more appropriate to the defensive minded Italian fleet, rather than the fanatical and aggressive Japanese. But of course the Italians had no carriers either.

[lwd]

My impression is that torpedo attacks were pretty much a crap shoot. If you get lucky they do a lot of damage if not ...
On the otherhand given that the Japanese got surprised by British planes at least once during the day time a night attack might catch them by surprise and increase the chances of hits considerably. Not sure how well the torpedo bombers could pick out the carriers at night though.

As for immediate persuit how would the Japanese know where to persue? Would they even be sure the planes were from carriers as opposed to land based? (The latter would depend a lot on exactly where they were).

[Keith Enge]

Given the slow speed of British carrier planes and the slow deck operating cycle (every plane struck below before the next one lands), it would be well after midnight before the carriers could recover their planes. This would leave them at most five hours of darkness to retreat. At 25 knots, this means 125 miles to which might be added the 175 miles (if the attack occurred at maximum search range). The British had at most a 300 mile head start. Given the speed and range of Japanese carrier planes (and even their searching floatplanes), this wouldn't be enough. The British force would have been found, caught, and destroyed. Somerville knew this which is why he had a secret base and retired as he did. His dispatches, of course, wouldn't say bluntly that the British presence in the Indian Ocean was too weak to contest control but that was the reality and both he, Pound, and Churchill knew it. His efforts, therefore, were a mere token to show that he was doing something while really doing nothing or, at least, nothing with any risk attached. It would be about two years before the Royal Navy contested the Japanese control of waters adjacent to South-East Asia; until that time, Japanese land-based airpower made anything else too risky. The Royal Navy hadn't forgot the fate of Force Z.

[dunmunro]

If Somerville had struck the IJN at night, he would have had many hours to withdraw out of range, especially since there is a high probability that one or more IJN CVs would be crippled, especially in the early evening hours of April 05.

There are two key suppositions here - and I am not convinced by either of them.

One that there would be severe damage to the Jap carriers. Two that the Japs wouldn't immediately be after him.

How can the IJN be "after" Somerville, if they haven't located his ships, and have no radar with which to plot the incoming and outgoing directions of the attacks? The IJN ships burn fuel just like any others and cannot move too far west for fear of exposing their tankers to attack. Somerville feared being caught with Nagumo between him and his bases, but Nagumo also had similar fears.

In the attacks against Bismarck, the Swordfish flew 24 attack sorties and scored 3 hits. If we apply the same hit percentage to an Albacore strike of say 40 aircraft, then it would produce about 5 hits.

[dunmunro]

. Not sure how well the torpedo bombers could pick out the carriers at night though.

The RN would use parachute flare to illuminate targets unless there was sufficient illumination and there was a partial moon that night as well:
http://www.moonconnection.com/moon_phas ... ndar.phtml

[Bgile]

[In the attacks against Bismarck, the Swordfish flew 24 attack sorties and scored 3 hits. If we apply the same hit percentage to an Albacore strike of say 40 aircraft, then it would produce about 5 hits.

Why would we do that? You don't see a difference between attacking a Japanese fleet and attacking Bismarck? I don't think very many of the TBD's at Midway even got a chance to drop a torpedo.

[dunmunro]

[In the attacks against Bismarck, the Swordfish flew 24 attack sorties and scored 3 hits. If we apply the same hit percentage to an Albacore strike of say 40 aircraft, then it would produce about 5 hits.

Why would we do that? You don't see a difference between attacking a Japanese fleet and attacking Bismarck? I don't think very many of the TBD's at Midway even got a chance to drop a torpedo.

Not really, especially since at night CAP would not be a concern. IJN AA was not very effective and IJN carriers were just as big targets as Bismarck.

[Bgile]

And IJN battleships and cruisers look just like carriers on radar. How many ships were sunk by Albacores at night? If this was a superweapon I'm really surprised it wasn't used all the time by everyone with no losses. For example, why wouldn't the USN have attacked Yamato at night? I suspect night attacks are very difficult and not nearly as effective as day attacks or day attacks wouldn't have been used at all. You are saying night attacks were much more effective than day attacks, right? Because the attackers wouldn't get hurt and the attacks were just as effective?

By the way, how did the Albacores find their own carriers and land on them at night?

[dunmunro]

And IJN battleships and cruisers look just like carriers on radar. How many ships were sunk by Albacores at night? If this was a superweapon I'm really surprised it wasn't used all the time by everyone with no losses. For example, why wouldn't the USN have attacked Yamato at night? I suspect night attacks are very difficult and not nearly as effective as day attacks or day attacks wouldn't have been used at all. You are saying night attacks were much more effective than day attacks, right? Because the attackers wouldn't get hurt and the attacks were just as effective?

By the way, how did the Albacores find their own carriers and land on them at night?

Night attacks are a way to avoid unpleasant encounters with CAP. If you have air superiority there's no reason to launch night strikes.

[dunmunro]

Given the slow speed of British carrier planes and the slow deck operating cycle (every plane struck below before the next one lands), it would be well after midnight before the carriers could recover their planes. This would leave them at most five hours of darkness to retreat. At 25 knots, this means 125 miles to which might be added the 175 miles (if the attack occurred at maximum search range). The British had at most a 300 mile head start. Given the speed and range of Japanese carrier planes (and even their searching floatplanes), this wouldn't be enough. The British force would have been found, caught, and destroyed. Somerville knew this which is why he had a secret base and retired as he did. His dispatches, of course, wouldn't say bluntly that the British presence in the Indian Ocean was too weak to contest control but that was the reality and both he, Pound, and Churchill knew it. His efforts, therefore, were a mere token to show that he was doing something while really doing nothing or, at least, nothing with any risk attached. It would be about two years before the Royal Navy contested the Japanese control of waters adjacent to South-East Asia; until that time, Japanese land-based airpower made anything else too risky. The Royal Navy hadn't forgot the fate of Force Z.

As we've discussed FAA aircraft are no slower than their USN and IJN counterparts in terms of cruise speed and Somerville did spend part of the evening of April 05/06 trying to find the IJN and hit them with a strike. RN carriers used crash barriers as per the USN and their recovery rate was just as fast. They did not have to wait for each plane to be struck below before recovering the next one.

Somerville did say bluntly that he was outnumbered and needed more and newer ships to make a stand and this is pretty obviously the case. The USN never attempted to fight a carrier battle so badly outnumbered as Somerville was in April 1942.

[RF]

How can the IJN be "after" Somerville, if they haven't located his ships, and have no radar with which to plot the incoming and outgoing directions of the attacks?

The same way the Japs found Yorktown at Midway. And they would indeed have been drawn further west.

[dunmunro]

How can the IJN be "after" Somerville, if they haven't located his ships, and have no radar with which to plot the incoming and outgoing directions of the attacks?

The same way the Japs found Yorktown at Midway. And they would indeed have been drawn further west.

Sorry, but that's not possible in this case. The IJN found Yorktown because a CV survived the initial strike and launched an immediate attack against Yorktown after an IJN search aircraft had located Yorktown about an hour after the first USN strikes were launched. If Somerville hit the IJN at sunset or after dark, they cannot reply and will have to wait for first light to even begin a search, and then wait at least another 2-3 hours before any possible sighting and strike launch. If Nagumo suffers damage to his carriers in the RN attack he will either have to slow his entire force or split his forces, and undoubtedly he would have simply retired eastward to Indonesia.

[Keith Enge]

dunmunro said

In the attacks against Bismarck, the Swordfish flew 24 attack sorties and scored 3 hits. If we apply the same hit percentage to an Albacore strike of say 40 aircraft, then it would produce about 5 hits.

. However, if we use that as the yardstick, we also have to include the fact that the Swordfish first attacked the light cruiser Sheffield. Therefore, in your hypothetical scenario, you have to include some "friendly fire" losses.

Someone asked how many warships were sunk by Albacores in night attacks. A more telling question is how many were sunk by Albacore in any attacks? As far as I know, the answer is none. In fact, I believe that British torpedo planes, carrier AND land-based sank a grand total of five ships destroyer sized or larger in the open seas (not in port) during the six years of war. Three of them were small Italian destroyers in July 1940; however, these were all done by Swordfish. Another was the Vichy French Chevalier Paul by Swordfish in June 1941 off Syria. The other was the Italian heavy cruiser Trento in June 1942 but that was done by a Beaufort (actually, she wasn't even sunk - a submarine had to finish her off).

Even if we include smaller ships like torpedo boats, the total is only increased by two. In March 1941, the Italian TB Andromeda was sunk by an aircraft torpedo but I don't know the plane type (from the date, it was likely a Swordfish). Much later, the incomplete German TB T61 was sunk by a Beaufighter. Once again, no Albacore victims. Let's face it, Albacores and all other British torpedo planes had a dismal record - they didn't get many hits and, when they did, the torpedo warheads were too small to sink their targets.

To put the British record in context, US torpedo planes sank 19 Japanese warships; only in four was the cause only aircraft torpedoes (the US liked combination attacks with divebombers too). Japanese torpedo planes sank nine Allied warships (two were solos, Chicago and McKean). Italian torpedo planes sank eight British Commonwealth warships; seven were solos (Bedouin was aircraft torpedo plus gunfire). The Germans which didn't even have torpedo planes for the first few years of the war managed to top the British; they had seven victims, all solos.

Expecting the Royal Navy to take on the Japanese in the Indian Ocean was therefore foolhardy. As the British author Peter C. Smith put it in one of his many books on WWII naval and aviation matters, "... India itself seemed under threat and Admiral Somerville was given five old battleships, two carriers with a complement of obsolete and outdated biplanes as their striking force, and an assortment of cruisers and destroyers with which to stop them if he could". A couple of sentences later, he goes on to state, "Fortunately, Admiral Somerville's main fleet never came into conflict with this powerful array of naval power, but two of his heavy cruisers, Cornwall and Dorsetshire, weren't so fortunate". I think this British author's assessment of the situation is accurate.

[dunmunro]

Commonwealth Naval aircraft
Torpedoes dropped_certain hits_probable hits_%_total certain and probable hits
609_____________167________37_______33.5

Naval Weapons of WW2, p81