Missed opportunity: US Navy land based P38D and P38E with dive flaps as a vertical dive bomber early 1942

[GrauGeist]

Dumbest idea I ever came across. If I was flying a dive bomber then I'd want a big chunky radial in front of me, not a twin with liquid cooled engines and leading edge condensers.

The Ju87 didn't have a radial engine...

 

[Shortround6]

The Ju87 didn't have a radial engine...

But at least it didn't have leading edge condensers

 

[michael rauls]

???????????????

Ya, you know. There just in front of the trailing edge condensers.

 

[P-39 Expert]

For Any of the above reasons, it is a mission that Never would be designed for.

Early '43 Lockheed ran tests on a P-38F carrying a 300gal tank and a torpedo. Flew out on the drop tank, dropped the torpedo and flew back on internal fuel. Asymmetrical forces were considered acceptable. P-38s later dropped 2000# bombs on sub pens.

 

[RCAFson]

Mid 1941, US Navy asks Lockheed to add dive flaps and a single bomb rack to a P38D and P38E for tests. US Navy tests these 2 aircraft with experienced dive bomber pilots, realizes they can outrun and out climb an F4F-3 while carrying a 1000 pound bomb at 25,000 feet. Even an unarmed F4F-3 can't catch them. They decide it would be a great land based dive bomber for defending ports.

I'm guessing an early P38 could maintain 350 mph with a 500 or 1000 pound bomb at 25,000 feet. That model Zero I believe was in the 300-315 mph range at 25,000 feet.

With trained navy dive bomber pilots, any japanese carrier that came within range of a land base with P38's so equipped would be at the mercy of the accuracy of the dive bomber pilots and nothing else.

Thoughts?

I don't think a P-38 could fit onto the elevators of then current USN carriers.

 

[pinsog]

I don't think a P-38 could fit onto the elevators of then current USN carriers.

I would agree. That's why the title says "US NAVY LAND BASED P38"

 

[pinsog]

Dumbest idea I ever came across. If I was flying a dive bomber then I'd want a big chunky radial in front of me, not a twin with liquid cooled engines and leading edge condensers.

If I was flying a plane unescorted, toward 2-4 Japanese carriers covered by 40+ Zeros which were one of the top 3 fighters on the planet at the time, flown by arguably the best pilots on the planet at the time, I would prefer to be in a turbocharged twin that could do 330-375 mph while carrying a 1000 pound bomb than in a single engine radial powered plane that could do 180-200 while carrying a 1000 pound bomb. Japanese flak in 1942 doesn't scare me (except for the golden bb/lucky shot) Zero fighters would scare me lifeless. It wasn't done, maybe it couldn't be done, but if possible that would have been my preference.

Before anyone says it, I believe the Dauntless was a superb dive bomber and all around fine aircraft.

 

[Shortround6]

Early '43 Lockheed ran tests on a P-38F carrying a 300gal tank and a torpedo. Flew out on the drop tank, dropped the torpedo and flew back on internal fuel. Asymmetrical forces were considered acceptable. P-38s later dropped 2000# bombs on sub pens.

The difference is in the speed/s flown or required. The forces go up with the square of the speed, Flying at 200mph in an Asymmetrical condition may be acceptable (consider how many twin engine planes made it back on one engine) trying to fly at over 300mph maybe another story.

I have no idea what the drop parameters of the MK 13 torpedo were in the spring of 1943. It started at the plane had to be under 50ft and flying slower than 100mph. By Midway it may have been up to 100ft and a bit faster (the B-26 handley exceeded the recommended drop speed, some people claim that by dropping higher and faster it would work but not low and fast or high and slow?) By early 1944 you could drop the MK 13 from up to 1000ft.

The torpedo may not care that the plane is flying a few degrees crabwise when it is dropped. However trying to "dive bomb" at higher speeds than the torpedo would tolerate being dropped at means higher forces. The bomb does not have a gyroscope to bring it back onto the correct bearing (even if offset a bit) You may well be able to drop the bomb in a dive with the airplane flying crabwise but the accuracy goes to pot. Pilot trying to retrim the aircraft while pulling out of the dive may not be good thing either, he is trying to retrim some of the other control surfaces at the same time.

It turns out that P-38s flying in formation and level bombing (how were the sub pens attacked?) showed less accuracy than formations of medium bombers for several reasons and the idea of the formations of P-38s being lead by droop snoots was allowed to to fade away.
A lot of techniques or tactics were tried. That certainly doesn't mean they all worked let alone were equal in effectiveness/accuracy.

The whole point of dive bombing was the greatly increased accuracy (more hits per number of bombs dropped) was considered a good trade off vs the dive bombers getting within range of small caliber AA guns. If your dive bomber, for whatever reason, is giving poor accuracy and still flying into range of the light AA guns then the whole thing needs a rethink.

Do you have a combat report for P-38s dropping 2000lb bombs on sub pens as the whole things sounds a bit off.

One P-38 Droop snoot did fly a mission to "monitor" the dropping of one or more 2000lb guided bombs but the planes carrying the bombs may have been B-17s.
Some articles say it was the GB-4 bomb but other articles say no GB-4 was used operationally ( which doesn't meant that the operation couldn't have used an earlier model)

Bombing coastal targets was also a common practice for squadrons/groups just working up (1st few combat missions) to get the pilots some experience rather than with any real expectations of hitting point targets. British were using 12,000lb Tallboy bombs against sub pens. They tried using British 2000lb AP bombs but they wouldn't penetrate the roof.
The US 2000lb bomb was GP bomb which would stand no chance of penetrating the roof. The US AP bomb was 1600lbs.

It could very well be true that P-38s dropped 2000lb bombs on a sub pen (or tried to) but a lot of the existing reports I can find in avery quick search seem to disagree with each other.

 

[michael rauls]

Maybe if there was a missed opportunity for the Navy to use the p38 to attack shipping it was with torpedos not as a dive bomber.
It sounds like it was more feasible.
Maybe even doable. But they were needed so badly as fighters and there was limited supply.

 

[Shortround6]

Maybe if there was a missed opportunity for the Navy to use the p38 to attack shipping it was with torpedos not bombs.
It sounds like it was more feasible.
Maybe even doable. But they were needed so badly as fighters and there was limited supply.

This can be argued both ways.
In 1941, early 1942 it might seem like a viable option except for the fact that the Navy was starting to get the first production Avengers which were much faster than the old Devastator (and carried the torpedo fully inclosed) and they were rigging the B-25s and B-26s with torpedo mounts. no real need for the P-38 to carry torpedoes too?

In hindsight it is a terrible idea, basically because the MK 13 torpedo didn't work. and the drop envelope was too restrictive. having to slow down to near stalling speed at less than 100ft above the water to keep from breaking the torpedo when it entered the water leaves the P-38 (or other large drop aircraft) way too vulnerable.

In addition to fixing things on the inside of the torpedo they added things to the outside

The plywood tail helped slow the torpedo and also helped make sure it entered the water at a good angle.
The wooden drum on the front broke up on impact with the water but cushioned the torpedo from the full impact.

These are what allowed (along with strengthening some parts of the torpedo) the MK 13 to be dropped at higher altitudes and higher speeds.

trying to drop the torpedo at 250-300mph in 1942 was about as effective as dropping a block of concrete 1-2000yds away from the target ship.

 

[GrauGeist]

No matter how fast your ingress is, you still have to slow down when you execute your dive.

THAT is when the enemy CAP will get you, and if they don't, the ship's AA will.

 

[Kevin J]

Okay so it was intercoolers not condensers, my mistake. Since someone brought up the subject of bombing submarine pens have any of you visited any of the towns where they were located. I've done Lorient in France. The pens are still intact and the whole town rebuilt. Yes, our glorious bomber boys missed 3 buildings, everything else was flattened.

 

[GrauGeist]

To be honest, the sub pens at Koroman were virtually indestructible - there was literally nothing that could destroy the structures.

 

[pinsog]

No matter how fast your ingress is, you still have to slow down when you execute your dive.

THAT is when the enemy CAP will get you, and if they don't, the ship's AA will.

And how many SBD's were brought down by AA fire at Coral Sea, Midway and the Guadalcanal campaign? Very very few. Zeros were the problem, if you got past them the big ships were in serious trouble.

The attack on Force Z, Prince of Wales and Repulse, by Betty and Nell twin engine bombers cost the Japanese 4 planes. How would that attack have gone if 2 dozen Wildcats had been flying CAP? CAP was the main threat, not AA

 

[Kevin J]

And how many SBD's were brought down by AA fire at Coral Sea, Midway and the Guadalcanal campaign? Very very few. Zeros were the problem, if you got past them the big ships were in serious trouble.

The attack on Force Z, Prince of Wales and Repulse, by Betty and Nell twin engine bombers cost the Japanese 4 planes. How would that attack have gone if 2 dozen Wildcats had been flying CAP? CAP was the main threat, not AA

We didn't have any Wildcats there. It would have had to be Buffalos.

 

[drgondog]

Early '43 Lockheed ran tests on a P-38F carrying a 300gal tank and a torpedo. Flew out on the drop tank, dropped the torpedo and flew back on internal fuel. Asymmetrical forces were considered acceptable. P-38s later dropped 2000# bombs on sub pens.

Asymmetrical loads at 150-175mph at less than 150 ft are very far from dive bombing at 350+mph. The P-38 drops in ETO in May June 1944 timeframe were level bombing guided by Droop Snoot lead w/bombardier. IIRC ONLY P-47D performed dive bombing with c/l bomb in ETO. I don't recall what 9th and 12th AF experience was re: dive bombing but AAF CAS doctrine emphasized level and shallow glide bombing at low altitudes in 1943.

 

[Shortround6]

If I was flying a plane unescorted, toward 2-4 Japanese carriers covered by 40+ Zeros which were one of the top 3 fighters on the planet at the time, flown by arguably the best pilots on the planet at the time, I would prefer to be in a turbocharged twin that could do 330-375 mph while carrying a 1000 pound bomb than in a single engine radial powered plane that could do 180-200 while carrying a 1000 pound bomb.

If my sole concern was to get to and from the target area with the best chance of my own survival the P-38 would be a great choice. However that total disregards effectiveness of the attack.
A P-38, without extensive modifications, simply cannot perform the mission. It is would be releasing the bomb much higher altitude and at higher speeds and quite possible flying a bit crabwise (yawed) to boot, all of which will degrade accuracy to greater or lesser extent.
The P-38 pilots would have a much better chance of surviving but then so would the Japanese carriers. Which then makes repeat strikes necessary, which doesn't help the survival odds of the pilots.


And again, to seize this "missed opportunity" means the US would have had to start planing for it in the summer or early fall of 1941 in order to have the planes ready in the summer of 1942.
This is a bit like saying that the US "missed the Opportunity" of greatly increasing the number of AA guns at Pearl Harbor and having them fully manned on Sunday morning.

Japanese flak in 1942 doesn't scare me (except for the golden bb/lucky shot) Zero fighters would scare me lifeless. It wasn't done, maybe it couldn't be done, but if possible that would have been my preference.

True oaf many navies in 1940/41/42, the Japanese had a major flaw in the AA gun defences with nothing in between the 4-5in AA guns and 25mm gun which was not very effective.

 

[pinehilljoe]

An interesting what it, but diverting any of the small 1941 P-38 production to the Navy would have taken direct intervention of the President. Many were assigned to the UK. As a previous poster said, defense of islands were the responsibility of the Army. One reason why I personally think GEN Short had to take responsibility, more than ADM Kimmel for Pear Harbor.

I think a more credible what if, is what if priority had been given to the Double Wasp and the Corsair? Could the Corsair have been operational 6 months earlier and been able to take part in Guadalcanal?

 

[P-39 Expert]

The difference is in the speed/s flown or required. The forces go up with the square of the speed, Flying at 200mph in an Asymmetrical condition may be acceptable (consider how many twin engine planes made it back on one engine) trying to fly at over 300mph maybe another story.

I have no idea what the drop parameters of the MK 13 torpedo were in the spring of 1943. It started at the plane had to be under 50ft and flying slower than 100mph. By Midway it may have been up to 100ft and a bit faster (the B-26 handley exceeded the recommended drop speed, some people claim that by dropping higher and faster it would work but not low and fast or high and slow?) By early 1944 you could drop the MK 13 from up to 1000ft.

The torpedo may not care that the plane is flying a few degrees crabwise when it is dropped. However trying to "dive bomb" at higher speeds than the torpedo would tolerate being dropped at means higher forces. The bomb does not have a gyroscope to bring it back onto the correct bearing (even if offset a bit) You may well be able to drop the bomb in a dive with the airplane flying crabwise but the accuracy goes to pot. Pilot trying to retrim the aircraft while pulling out of the dive may not be good thing either, he is trying to retrim some of the other control surfaces at the same time.

It turns out that P-38s flying in formation and level bombing (how were the sub pens attacked?) showed less accuracy than formations of medium bombers for several reasons and the idea of the formations of P-38s being lead by droop snoots was allowed to to fade away.
A lot of techniques or tactics were tried. That certainly doesn't mean they all worked let alone were equal in effectiveness/accuracy.

The whole point of dive bombing was the greatly increased accuracy (more hits per number of bombs dropped) was considered a good trade off vs the dive bombers getting within range of small caliber AA guns. If your dive bomber, for whatever reason, is giving poor accuracy and still flying into range of the light AA guns then the whole thing needs a rethink.

Do you have a combat report for P-38s dropping 2000lb bombs on sub pens as the whole things sounds a bit off.

One P-38 Droop snoot did fly a mission to "monitor" the dropping of one or more 2000lb guided bombs but the planes carrying the bombs may have been B-17s.
Some articles say it was the GB-4 bomb but other articles say no GB-4 was used operationally ( which doesn't meant that the operation couldn't have used an earlier model)

Bombing coastal targets was also a common practice for squadrons/groups just working up (1st few combat missions) to get the pilots some experience rather than with any real expectations of hitting point targets. British were using 12,000lb Tallboy bombs against sub pens. They tried using British 2000lb AP bombs but they wouldn't penetrate the roof.
The US 2000lb bomb was GP bomb which would stand no chance of penetrating the roof. The US AP bomb was 1600lbs.

It could very well be true that P-38s dropped 2000lb bombs on a sub pen (or tried to) but a lot of the existing reports I can find in avery quick search seem to disagree with each other.

Source was Warren Bodie's "Lockheed P-38". Just using the torpedo as an example for weight/drag to approximate a 1000-2000# bomb. If the bugs had been worked out of the torpedo then maybe a different story. His quote about bombing the sub pens. I still think this would work, but more of a glide bombing or skip bombing mission. B-25s skip bombed, but the P-38 could have been unescorted.

 

[P-39 Expert]

An interesting what it, but diverting any of the small 1941 P-38 production to the Navy would have taken direct intervention of the President. Many were assigned to the UK. As a previous poster said, defense of islands were the responsibility of the Army. One reason why I personally think GEN Short had to take responsibility, more than ADM Kimmel for Pear Harbor.

I think a more credible what if, is what if priority had been given to the Double Wasp and the Corsair? Could the Corsair have been operational 6 months earlier and been able to take part in Guadalcanal?

Corsair's first combat missions were in Feb '43 at Guadalcanal.