XP-39 II - The Groundhog Day Thread

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i'm not sure if it fits here but were the P39 and P40 all steel and the P51 aluminum? Curious about the aluminum P40 what if....
 
P-39 and P-40 are aluminum airplanes. At least the ones operated by the Planes of Fame are. There is some steel, but the structure is aluminum. Landing gear oleos are steel along with a few other items. The engine crankshaft, camshaft, and other parts are steel, but the engine case is aluminum. Mixed material is normal due to strength and heat requirements.

If you tried out aluminum valves in the engine, they wouldn't last longer than a couple of minutes, if that long. In an Allison V-1710, the valve are Stellite (cobalt-chromium alloy) with powdered sodium fill for heat dissipation.
 
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I'd imagine a cast-iron block engine would yield an airplane which is capable of taxiing. Only.

Were the valve seat also made of Stellite? Very strong material.
 
Thanks for the correction on the Nates. I blame spell check. LOL

Good points.
 
Interesting. Couple books and articles I've read said the units (like 8th FG) with P400 fared not-so-well against the IJNAF fighters, early in those New Guinea air battles. Later, these early units were replaced with P40s.
I think it was along the lines of, 'escort mission covering B-25s (or B-26s or B-24s) along with P-40s.' I'll have to look for it to be sure I'm recalling it correctly.
 
I think it was along the lines of, 'escort mission covering B-25s (or B-26s or B-24s) along with P-40s.' I'll have to look for it to be sure I'm recalling it correctly.
OK, I was confusing the P-38 book with the P-39 book; the P-38s were on escort missions with P-40s.
The P-39s fought with RAAF Kittyhawks in New Guinea, mostly on intercept missions. The P-39s did escort RAAF B-26s, USAAF B-25s, A-20s, and A-24s.
Here are a few screen shots:
 

Peter,

Thank you! The numbers look fairly close (I don't have them memorized). Did the Germans use Allied fuel to get these results? Did Allied fighters and bombers use the same grade fuel? I would guess it was all the same...

Cheers,
Biff
 

Ivan,

I can easily see the Russian pilots over boosting their planes, for the simple reason as you said they didn't tend to last long. Also, as for the P39 it was someone else who was building it and its engines, so no skin in the game and it was truly an asset to be used up and thrown away. And it appeared to have less vices than their indigenous production.

As for the Zero and it's top speed I agree. I always thought of it being a 350'ish type of plane mostly because of what the combat reports said (Allied pilot reports). It's fairly easy to compare your planes performance to another even in a fight. It's quite obvious who is faster, and by how much, or who turns / climbs better and by what sort of margin.

Cheers,
Biff
 
Did the Germans use Allied fuel to get these results? Did Allied fighters and bombers use the same grade fuel? I would guess it was all the same...

Cheers,
Biff

Allied bombers generally used 100/130 grade fuel while USAAF 8th AF Mustangs used 100/150 GRADE FUEL starting in early June 1944. 9th AF used 100/130 grade after moving to the continent. RAF Mustangs, some Spitfires, Mossies and Tempests starting using 100/150 Grade in ADGB (Air Defense of Great Britain) during the summer of 44, with 2nd TAF fighters switching over in early 45 on the continent.
 

What's the book? Some operational history and pilot's accounts of the P-39 would be most welcome here instead of the endless drama over trivial matters and ongoing personal smears.
 
What's the book? Some operational history and pilot's accounts of the P-39 would be most welcome here instead of the endless drama over trivial matters and ongoing personal smears.

(my bold)
I have nothing against keeping the bolded stuff in a single thread, vs. having to wade through that multiple threads...
 

At least before 1945, most Russian pilots fought over Russian soil. So, if they fried an engine --- bailing out & survival was not as harrowing, as a German pilot bailing out over the same territory.
 

Mike,

I would not have guessed that, however it stands to reason due to shear quantities. What happened when a fighter guy diverted / landed short at a bomber base, did they have a supply of the 100/150 or did he get 100/130 and use lower power settings on the way home?

Cheers,
Biff
 
On missions from the UK, when really short of fuel returning planes landed at the three emergency bases set up for the purpose RAF Manston Woodbridge or Carnaby. I presume they had all sorts of fuel, they had everything else.
 

Hi Biff,
One example that comes to mind is Operation of Spitfire IX LF with 25 lbs/sq.in. Boost. "Aircraft may land at an airfield where only 130 grade (normal 100 octane) fuel is available. The pilot should always bear in mind that it is not harmful to use this fuel provided he does not REPEAT not exceed 18 lbs. boost." 8th AF mustangs could use 2nd TAF's 150 grade on the continent beginning in early 1945, otherwise I presume they would use 9th AF stocks of 100/130 fuel and limit boost for the ride home.
 
Does any one know what kind of fuel Russian P-39s used?
Not sure what was used in the Soviet P-39 specifically, but they did have aviation fuel that ranged from 70 to 85 octane, with fuel supplied to them by the Allies that was 95 and 100 octane.

The lower octane fuel was used in older aircraft types.
 
Does any one know what kind of fuel Russian P-39s used?

front line units usually used 91-95 oct Soviet fuels or 100 oct LL fuel (outside mid-1942 - early 43, when Soviet fuel supply was in crisis), I have seen Soviet speed graphs for P-39Q showing the speeds with 95 and 100 oct fuel. Soviet 95 oct was usually used by M-82F and FN engines, so La-5F, -FN, La-7 and Tu-2. Spitfires and P-39s used usually 100 oct LL fuel. IIRC one big offensive was delayed a couple of days so that they could store enough LL fuel for a P-39 fighter division for the operation.
 
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