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Understood. I'm curious if any other members, such asI believe it was under the nose or under the centre wing area. Hard to tell.
Another design that I had some interest in would be the XP-54: Of all the R-40C designs, it had the most potential in terms of being a workable design. It had a method for cockpit egress and avoiding getting turned into ground-meat from the propellers.
It seems the problem was that it got too heavy, and I'm curious why.
An indication of how big the XP-54 was is that the centre fuselage was longer than the Spitfire, P-51, P-47, Tempest V, Fw 190D-9, Ta 152H and is only a few inches shorter than the P-38.
It's overall length was longer than the P-61, A-26 and Mosquito and only slightly shorter than a B-26 Marauder.
What factors drove up the aircraft's overall size?It got big!
Why was the pressurization system a requirement? The P-51 and P-47's both flew at similar altitudes and didn't require it.Part of the problem was the pressure cabin, which dictated the egress system.
I thought the traversable guns was just something Vultee adopted on their own initiative...Then there was using two 37mm M4 cannon and two 0.50" HMGs, and then needing a compensating mechanism so that the cannon and machine guns hit the same target. The original scheme was for all 0.50" HMGs or a combination with 20mm cannons.
The H-2600 and H-2470 both weighed 2400 pounds, with the R-2160 weighing 2350. Power output varied by about 50 horsepower maximum. The reconfiguration of the engine mounts might have played a role.The design was originally to have the XH-2600 (X-1800), then went to the XH-2470. It was planned to use the XR-2160 Tornado when that became available, so the structure to support that engine, which was heavier and more powerful
What factors drove up the aircraft's overall size?
Why was the pressurization system a requirement? The P-51 and P-47's both flew at similar altitudes and didn't require it.
I thought the traversable guns was just something Vultee adopted on their own initiative...
The H-2600 and H-2470 both weighed 2400 pounds, with the R-2160 weighing 2350. Power output varied by about 50 horsepower maximum. The reconfiguration of the engine mounts might have played a role.
Was there any change in altitude requirements from the earliest proposals of the XP-54 to the flying models?
Also, what did the XP-68 proposal look like?
I'm just surprised that the early design they were working on used an Allison V-1710 without a turbo. I figure they'd have wanted to get that turbo on the design with a vengeance, or adopt a twin-stage set-up, if they wanted high-speed performance (the best place to get it would be at altitude). After all, the P-40 only ended up with a single-stage supercharger because the turbocharged designs (XP-37/Y1P-37) didn't have enough visibility over the nose.The requirements put on it by the USAAF.
Supposedly the design went from around 11000 pounds with a wing area in the 200-300 square foot range to 456 square feet, and weight went up to around 15000-19000 pounds when it was loaded.Because the Army wanted it.
Never heard anything to say it couldn't: The P-47 routinely operated in the 25000-30000 foot range and if you had no oxygen, you'd be dead in a matter of seconds or minutes. B-17 crews operated around 25000 feet a lot and they flew missions that were several hours in length. If anybody would have had detrimental effects, they would have been more likely.I don't know if the P-51 and P-47 could fly at high altitude for prolonged periods without detrimental affects for the pilot.
So they came up with this on their own initiativeThe Army specified the armament and Vultee came up with a system to make it work
Jets were on the horizon.Why'd the US Navy cancel the H-2470? Also, I'm curious if the USAAF could have taken over the funding if the USN cancelled it
Anybody who's had a chamber ride can tell you. Above FL 350-360 breathing 100% O2 with an ambient pressure regulator doesn't supply enough partial pressure of oxygen in the blood to stave off hypoxia, so pressure breathing becomes necessary, a very taxing and exhausting exercise. Above approx 450, ambient pressure is not enough to keep the nitrogen in the blood in solution, and it literally "boils" out, resulting in instant death by eruption. If you're going to operate in that altitude range or higher, you need pressurization or a pressure suit, or both.I don't know if the P-51 and P-47 could fly at high altitude for prolonged periods without detrimental affects for the pilot
What reasons? I just thought the issue had to do with specialized high altitude fighters.It was assumed by many in the planning departments/purchasing that the altitudes at which combat took place would keep going up. Which is why the Americans, British, Germans and others had designs/schemes for planes with pressurized cockpits all in the works in 1941-42. However, for a variety of reasons this did not happen with piston engines. At least not to the extent the planners thought.
The problems I can see with the guns are temperature related, as for the radios and instruments, I'm surprised altitude would have much effect. As for engine ignition systems, why would that cause a problem?Problems with guns, radios, instruments and even ignition systems on the engines kept the combat ceiling lower than expected in addition to...
Jets were on the horizon.