Groundhog Thread Part Deux - P-39 Fantasy and Fetish - The Never Ending Story (Mods take no responsibility for head against wall injuries sustained)
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Shortround6
Major General
The US testing procedure for climb was to use military power for 5 minutes and then reduce power to normal or max continuous. A fast climbing plane could hit 15,000 ft in 5 minutes. A slow climbing plane might just clear 10,000ft. If you compare the climb rate at 20,000ft they might be closer than the time to 20,000ft might suggest.
The Allison was running at 3000rpm for military power and 2600 rpm for "normal" or max continuous. Which had no time limit (as long as the fuel lasted
The Merlin was rated at 3000rpm for full power or Military.
However climb rating was at 2850rpm for all but the early versions. But the climb rating was supposed to be used for 30 minutes or less. Obviously but unfortunately neither method tells us what the plane would do at the higher altitudes in combat, at full or military power.
The Allison was running at 3000rpm for military power and 2600 rpm for "normal" or max continuous. Which had no time limit (as long as the fuel lasted
The Merlin was rated at 3000rpm for full power or Military.
However climb rating was at 2850rpm for all but the early versions. But the climb rating was supposed to be used for 30 minutes or less. Obviously but unfortunately neither method tells us what the plane would do at the higher altitudes in combat, at full or military power.
Thumpalumpacus
Major
Six fifties up in your face, yo.
GrauGeist
Generalfeldmarschall zur Luftschiff Abteilung
Yeah...a glaring example would be my WWI German skin project for the Bf109 in IL-2: Sturmovik back around '08 (which involved considerable research and graphics work).
They didn't exist anywhere on the interwebs until I posted them in our gaming forum. It wasn't long after, that identical skins started popping up here and there in gaming forums and several "skin masters" laid claim to innovating the concept...
Well, to all those "experts" out there:
you're welcome.
GrauGeist
Generalfeldmarschall zur Luftschiff Abteilung
Nooooo...the first Grummans the British received were French G-36As.
Therefore it would have been the "La Chat Sauvage"
ThomasP
Senior Master Sergeant
Hey Shortround6,
For the UK the Merlin XX series Climb rating (2850 rpm) was increased to 1 hr limit in early-1943.
For the V-1650-1 the US used 2650 rpm for maximum continuous (Normal) but had no separate Climb rating, at least not early-war. This is part of the reason why the P-40F did not have any significant ROC advantage in the US specifications literature. I have not been able to find any V-1650-1 Specific Engine Flight Charts dated after December 1942, so I do not know if this situation ever changed.
The UK and RAAF, on the other hand, used the UK Climb rating (2850 rpm) for the V-1650-1 in their P-40Fs.
Interesting mix.
For the UK the Merlin XX series Climb rating (2850 rpm) was increased to 1 hr limit in early-1943.
For the V-1650-1 the US used 2650 rpm for maximum continuous (Normal) but had no separate Climb rating, at least not early-war. This is part of the reason why the P-40F did not have any significant ROC advantage in the US specifications literature. I have not been able to find any V-1650-1 Specific Engine Flight Charts dated after December 1942, so I do not know if this situation ever changed.
The UK and RAAF, on the other hand, used the UK Climb rating (2850 rpm) for the V-1650-1 in their P-40Fs.
Interesting mix.
Greg Boeser
1st Sergeant
Possibly the funniest anecdote was a game designer who flew for Delta posted his harrowing first trip to Japan during the earthquake in 2011. He sent his followers a post to let them know he was safe and recount his experience. Well, someone forwarded it on to a friend and the next thing we know its all over the internet., he's getting called on the carpet for violating company policy about speaking to the press, and there are online debates raging about the authenticity of the story.
That's right, the French order was de-Francofied by Grumman on the production line, before being sent to Scotland, where they were assembled by Scottish Aviation. The first Aeronavale 'Chat first flew on 10 May 1940, the day the Germans began their invasion. This is unlike the Curtiss Hawk 75s that arrived in the UK fully Francofied and required alteration before entering RAF service.
Actually I got something wrong in my previous post, 804 Sqn was the first British unit to receive those ex-French Martlets in October 1940, with 802 being formed from those 804 Sqn aircraft, in November. An 804 Sqn Martlet scored the type's first combat victory, over a Ju 88 in December.
glennasher
Senior Airman
I had to laugh at the quote below the ww2aircraft.net search: "I think the best solution would be to scrap the P-39"
Thank you and you're welcome! For whatever reasons, I've never been a fan of the 39. I won't apologize for that, apparently the USAAF felt the same way, it was used only because it was all they had at the time, and they gave them away whenever possible, or used them for target practice, which says a heckuva lot, right there.
History would be very different if the delivery schedules and state of readiness of the P-39 and F4F were reversed.
fastmongrel
1st Sergeant
I would rather face a Grumman Wildcat than an angry Wildcat (Felis Silvestris). You have a chance of bailing out of the plane unscathed the cat will hang on and shred you
Peter Gunn
Master Sergeant
If it makes you feel better I can dislike your post too, or even give it the "Dumb" tag. Your choice.
Ooooh, dumb tag please!
Peter Gunn
Master Sergeant
Your command is my wish.
MIflyer
1st Lieutenant
The situation between the F4F and the P-40/P-39 is an interesting one.
When the USAAC bought the YB-17 the USN realized that the vision of Gen Billy Mitchell was about to come true. When the USAAC intercepted the Italian liner Roma far out at sea, the USN got so scared they got Army HQ to forbid any such operations. When the tubosupercharged Y1B-17 came out the USN knew they had a huge problem. The Navy's carrier force was created to prevent the sitting duck situation that Billy Mitchell exploited in his demonstration. But while the F2A was an improvement over the F3F biplane, the Y1B-17 had a top speed equal to the F2A, but at TEN THOUSAND FEET higher. In wargames this would be fatal. In the pre-radar days of the 1930's, the first the USN would know of a Y1B-17 attack was when one appeared overhead. There was no chance of an F2A intercepting a Y1B-17, even if somehow they were able to see the bomber coming.
The first war any weapons system has to fight is in DC. After Mitchell's demonstration against the battleships the Washington Times headlines screamed that battleships were a waste of money; 15 years later it was all coming true. The USN was set up to lose the Battle of DC.
So the USN got with Grumman and reworked its failed competitor to the F2A with a two-stage mechanically supercharged engine, as was demonstrated by the Republic XP-41 - and rejected by the USAAC due to the superior performance of the tubosupercharged version of the same airplane, the AP-4; the result was the P-43. The Navy took the P-41 powerplant and added it to the F4F to produce the world's first two stage supercharged high altitude fighter to go into service.
The USAAC had been focused on the turbosupercharger as the answer to superior performance ever since the GE Pikes Peak test during WWI. But installing a turbo in a single-engined airframe proved to be too difficult with the available airframes and powerplants of the time. The XP-37 was a P-36 with a V-1710 and a turbo, but the cockpit had to be moved absurdly far aft, even if it was 50 mph faster than a P-36 above 20,000 ft.
On the XP-39 the turbo caused so much drag that the airplane was slower with it than without.
Eventually the USAAF got the P-38 and P-47 developed and deployed, proving that the turbo could do the job in a fighter as well as a heavy bomber, but in the meantime the USN's F4F was the only US fighter that enough high altitude performance to challenge the Zero and knock down the Betty bombers over Guadalcanal.
And ironically, it was the B-17 that scared the Navy into buying the F4F.
Now, if y'all will excuse me, I have to go put some paint on certain 1946 airplane.
When the USAAC bought the YB-17 the USN realized that the vision of Gen Billy Mitchell was about to come true. When the USAAC intercepted the Italian liner Roma far out at sea, the USN got so scared they got Army HQ to forbid any such operations. When the tubosupercharged Y1B-17 came out the USN knew they had a huge problem. The Navy's carrier force was created to prevent the sitting duck situation that Billy Mitchell exploited in his demonstration. But while the F2A was an improvement over the F3F biplane, the Y1B-17 had a top speed equal to the F2A, but at TEN THOUSAND FEET higher. In wargames this would be fatal. In the pre-radar days of the 1930's, the first the USN would know of a Y1B-17 attack was when one appeared overhead. There was no chance of an F2A intercepting a Y1B-17, even if somehow they were able to see the bomber coming.
The first war any weapons system has to fight is in DC. After Mitchell's demonstration against the battleships the Washington Times headlines screamed that battleships were a waste of money; 15 years later it was all coming true. The USN was set up to lose the Battle of DC.
So the USN got with Grumman and reworked its failed competitor to the F2A with a two-stage mechanically supercharged engine, as was demonstrated by the Republic XP-41 - and rejected by the USAAC due to the superior performance of the tubosupercharged version of the same airplane, the AP-4; the result was the P-43. The Navy took the P-41 powerplant and added it to the F4F to produce the world's first two stage supercharged high altitude fighter to go into service.
The USAAC had been focused on the turbosupercharger as the answer to superior performance ever since the GE Pikes Peak test during WWI. But installing a turbo in a single-engined airframe proved to be too difficult with the available airframes and powerplants of the time. The XP-37 was a P-36 with a V-1710 and a turbo, but the cockpit had to be moved absurdly far aft, even if it was 50 mph faster than a P-36 above 20,000 ft.
On the XP-39 the turbo caused so much drag that the airplane was slower with it than without.
Eventually the USAAF got the P-38 and P-47 developed and deployed, proving that the turbo could do the job in a fighter as well as a heavy bomber, but in the meantime the USN's F4F was the only US fighter that enough high altitude performance to challenge the Zero and knock down the Betty bombers over Guadalcanal.
And ironically, it was the B-17 that scared the Navy into buying the F4F.
Now, if y'all will excuse me, I have to go put some paint on certain 1946 airplane.
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Admiral Beez
Captain
I was trying to share my dislike and agreement with your Dislike of another P-39 threadjacking.
P-39 Expert
Non-Expert
Here's the Bell drawings showing that the rear engine compartment is exactly the same size on both the P-63 (which had the auxiliary stage supercharger) and the P-39 (which did not).
Regarding moving the radio from the tail cone to above the engine, there are numerous public photos to verify that.
Attachments
FLYBOYJ
"THE GREAT GAZOO"
Errrr - no. that is not an engineering drawing that shows a radio installation, all you're showing is station locations and skin thickness. "Could have, would have. should have." Face it, there is NO Bell installation for the movement of the radio to another part of the aircraft that "could have" or was actually done to any P-39 operated by the AAF in a combat situation, once again you're trying to fabricate something that never existed to sustain your argument. We (those of us who have actually weighed aircraft) have showed you that in the factory configuration, you cannot remove the front armor on any model of the P-39 without moving the C/G beyond aft C/G limits when expelling all the cannon ammunition and allowing the fuel to go below 1/4 full. Go back and look at the W&B chart the Greg put together. Now please put it to rest!!!!
