Navalized P-38/39/40: pros cons

[parsifal]

Well, those landings are tight, but i would put this clip up against it and claim the landing was even tighter. HMAS Melbourne, 12000 ton Light Carrier . From Flight Deck Ops, the wing would pass over your head as the bird was landing. Tracker pilots getting their carrier qualifications.

After 1975, only RAN pilots were crazy enough to land on the old girl. Yanks thought our guys were nuts. In hindsight, they were probably right


View: https://www.youtube.com/watch?v=HoEElPX8hfQ

 

[FLYBOYJ]

But I don't think they ever LANDED a B-25 on a WWII carrier.

 

[pinsog]

How much weight did the silly car door add to the P39 over a standard canopy?
What would an extra 6 inches per wing do for low speed handling on a P39? What would effect be on performance and maneuverability?
What would an extra 1 foot per wing do for low speed handling on P39? Would would be the effect on performance and maneuverability?

 

[GrauGeist]

How much weight did the silly car door add to the P39 over a standard canopy?

it would probably take a good deal redesign for the fuselage to accept a sliding canopy as the engine cowling and intake are located directly behind the cockpit...

 

[bobbysocks]

run that poor Lycoming up until it was screaming for mercy

that is the first time I have heard that expression used in like forever....lol

a good pilot can put anything down on a carrier if they wanted.....

 

[Shortround6]

it would probably take a good deal redesign for the fuselage to accept a sliding canopy as the engine cowling and intake are located directly behind the cockpit...

Simple. Rear canopy stays in place. Wind screen/front canopy slides forward

Bailing out at speed might be a slight problem

A sliding bubble was done on the P-63E but I have no idea how much trouble it was or if the shorter length canopy hurt performance (higher drag?)

 

[GrauGeist]

Simple. Rear canopy stays in place. Wind screen/front canopy slides forward

Bailing out at speed might be a slight problem

A sliding bubble was done on the P-63E but I have no idea how much trouble it was or if the shorter length canopy hurt performance (higher drag?)

Sliding foreward would also present a problem, because the weapon bay access would have to be modified, too.

Bell could have made the canopy based on Messerschmitt's "side-swing" design, perhaps...

In any case, the layout of the P-39 made any other type of canopy very difficult to consider.

 

[wuzak]

Sliding foreward would also present a problem, because the weapon bay access would have to be modified, too.

It could have slid rearwards, Spitfire style.

Or, for a proper bubble canopy, rework the air intake.

 

[GrauGeist]

It could have slid rearwards, Spitfire style.

Or, for a proper bubble canopy, rework the air intake.

But like I mentioned before, the rear portion of the cockpit/canopy is part of the engine cowling.

I am willing to bet that Bell took all the current canopy types into consideration when they designed it and this was the most economical and effective design.

I'm sure that a bubble canopy may have been easier to install on a hurricane than a P-39.

 

[GregP]

Regarding POST 82, that's astounding, Was that done more than once, or was that a trial only?

I'm trying to figure out where they attached the arrester hook, structurally. Not that it would be prohibitive almost anywhere, but just from curiosity. I can't imagine it was more than a test

I see it happened in 1944 aboard the Shagri-La. Had not heard that. I pretty sure the Doolittle raiders were all put aboard the carrier with a crane at Alameda.

 

[GrauGeist]

Regarding POST 82, that's astounding, Was that done more than once, or was that a trial only?

I'm trying to figure out where they attached the arrester hook, structurally. Not that it would be prohibitive almost anywhere, but just from curiosity. I can't imagine it was more than a test

I see it happened in 1944 aboard the Shagri-La. Had not heard that. I pretty sure the Doolittle raiders were all put aboard the carrier with a crane at Alameda.

The Navy was using a Marine Corps PBJ-1H that had the arrestor hook anchored to the tail-skid mount.

They trialed it several times, under varying conditions in both T/O and landing. The Navy ultimated decided not to pursue it further, even though the trials were successful.

And yes, the Doolittle raiders were craned aboardship.

Here's the USMC PBJ-1H (43-4700 - BuNo. 35277) seen aboard the Shangri-La during trials:

 

[GregP]

We usually fly our B-25J with the side gun mounts as seen here, but also with the clear bomber nose (not the solid gun nose). The side gun mounts take off about 12 knots or so, so we usually remove them for photo missions.

When I say "we," I mean Planes of Fame, not specifically Greg.

 

[Peter Gunn]

How much weight did the silly car door add to the P39 over a standard canopy?
What would an extra 6 inches per wing do for low speed handling on a P39? What would effect be on performance and maneuverability?
What would an extra 1 foot per wing do for low speed handling on P39? Would would be the effect on performance and maneuverability?

On the canopy, I always thought Bell did quite a remarkable job with it considering the engine intake etc. Also, did the door add any extra weight over what would have been solid fuselage? If so, how much? Valid questions from me, not being combative.

Also I thought that Bell came up with a pretty good "almost a bubble" canopy solution with that, certainly closer than a P-40, 47, 51, Corsair, Spitfire, Hurricane etc. had in their first iterations.

 

[tomo pauk]

The excess weight of the P-39 vs. Euro-Asian fighters of the era comes out from excess weight of guns & ammo, not from the 'silly car dors'. That and cockpit canopy were the last of the worries.
Agains most of European designs powered by V-12 engines, it aso carried a bit more fuel, that again adds weight, so do the up to 3 radios.

 

[pinsog]

The excess weight of the P-39 vs. Euro-Asian fighters of the era comes out from excess weight of guns & ammo, not from the 'silly car dors'. That and cockpit canopy were the last of the worries.
Agains most of European designs powered by V-12 engines, it aso carried a bit more fuel, that again adds weight, so do the up to 3 radios.

Agreed. I know it was over armed for its horsepower. I thought they might save some weight by doing a standard canopy (I think I saw on this site somewhere that the car door added several hundred pounds because of the way it had to be built. But that may not be right) and of course making it easier to bail out of

I know the P39 had low speed handling issues, would 6 inches or so added to each wing solve the low speed handling?

I like the idea of a P39 for the US Navy. Slightly longer wings that fold for better low speed handling, ditch the wing guns and put wing tanks in there place for better range, keep 2 synchronized 50's and the 37mm, fix the ejection chute on the 37mm so it is reliable, ditch part of the armor and some of the radios. The P39 is very fast, P39C climbed exceptionally well, had great performance below 15,000 feet, and if the 37mm was reliable it would be awesome at dropping Kate torpedo planes before they got to the carrier.

 

[tomo pauk]

Fuselage of the P-39 weighted ~620 lbs, containing also the engine. Fuselage of the P-40B weighted 420 lbs, add the weight of the engine section - 300 lbs - for total of 720 lbs. So maybe we could see some saving in not having car dor entry, I'm not too sure the weight savings is in the range of 'several hundred pounds'

 

[Shortround6]

One analysis of the P-39 claims 50lbs for the drive shaft and 50lbs worth of fuselage "stiffening" to keep the Propeller in line. No mention is made of the canopy or doors. You do need to keep the fuselage flex to a minimum if the prop is 10 feet away from the engine. Perhaps if the doors were not there, that section of the fuselage could have been made lighter?

 

[GrauGeist]

...I thought they might save some weight by doing a standard canopy (I think I saw on this site somewhere that the car door added several hundred pounds because of the way it had to be built. But that may not be right) and of course making it easier to bail out of...

I would love to see that source, as the door of the P-39 was constructed mostly of aluminum.

For comparison, the driver's door on my 1966 Mustang weighs under 100 pounds and that's with window regulator bellcrank, glass and track plus latch and release/handle assembly.

 

[pinsog]

I have no idea where I read that the P39 gained a lot of weight do to the car door cockpit, I think I read it on here, but I read so much in so many places I can't give a source and it may be completely wrong. I make no claims either way, that is why I asked for verification. I thought they said it had to do with the extra structure required elsewhere to stiffen it back up because of the big gaps in both sides of the fuselage (like cutting the roof off a normal ca to make a convertible)

 

[GrauGeist]

If you go back to my post #87 and look at the P-39's diagram, you'll see the subframe assembly that the cockpit attached to.
The cockpit subassembly would have added additional weight to the total airframe weight, but it also tied in with the airframe, adding additional strength.

As it is, removing the car doors and installing a conventional canopy wouldn't help the weight issue much, as the cockpit subassembly would still exist as a component.

Again, referring to the diagram, you can see how the cockpit is designed to be removed in it's entirety in order to perform extended maintenance