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Careful, you're using facts to destroy a widespread article of faith. Everyone knows that the Spitfire was fragile; in fact, it's astonishing they ever made it into the air.The Spit IX and later the Spit XVI were the main a/c used by the 2TAF in NE Europe. They could be dived up 60 degrees.
I think the Russians actually preferred the P-40K though with the Allison engine because they were fighting down low for the most part. They got about 100 P-40Fs but sent them right to PVO units (air defense). Allison engine P-40s seem to also have been preferred in the CBI.
One question I have is why weren't the Allison engined P-51s a bit more widely used in the Med? They did have them but were using them as dive bombers and recon planes mostly.
Power to weight is what makes an aircraft "0ver weight"
Once you get a Allison P-40 to 15,000ft or so you have an 1150hp engine in an 8,000lb plane and as you go higher it gets worse.
P-38 likewise a had a much better power to weight ratio at altitude due to the turbos. A late model P-38 had four times the power at 25,000ft that a P-40N did. It sure didn't weigh four times as much.
A P-40 with a V-1650-7 might have been a very dangerous opponent but i.
British try using bombs as air to air weapons as Spitfires are too fragile for ground attack
Yes the Spitfire was not as desirable as some other aircraft for ground attack (Typhoons with hundreds of pounds of extra armor?) and P-51s were more susceptible to ground fire/battle damage than P-47s but both Spitfires and P-51s performed many ground attack missions.
Production numbers and spare parts answer those questions. (snip) There simply weren't enough Merlin P-40s to scatter around to too many different theaters.
sending a few squadrons of P-40F/Ls to lesser theaters without adequate spare parts (not just the engines, the Merlin and Allison needed different radiators and oil coolers) is going to result in a lot of effort for not much result.
The numbers tell the story of the Allison P-51/Mustang/A-36 too.
There were roughly 1580 Allison Mustangs built. (snip)
The 500 A-36s kept 3 fighter bomber groups (9 squadrons?) in action for quite some time, over a year?
I'll just skip the 'what-ifs' with you guys lol...
But production doesn't tell the whole story and in fact proves misleading. They may have built 5,000 P-40Ns but by the time the N came out, the urgency for using P-40s was over. The P-40F and L models, conversely, were available at the most critical moment. They had enough of them to be the main variant in use by no less than 5 USAAF fighter groups in the Med / Italian Theaters: 33 FG, 324 FG, 325 FG, 57 FG and 79 FG were all mainly using merlin engined P-40s, as well as some P-40K.
5 Fighter groups with 3 squadrons each = 15 squadrons, (that's a little more than 'a few'), operating during the most critical months on the war, they played a key role in finally and decisively securing the English supply route from India, taking one of the major Axis powers (Italy) out of the war and forcing vast amounts of German resources to be redirected to cover their southern flank, not a "lesser Theater" in my opinion, though I know some perceive it that way.
Actually again, not of that actually tells us much of anything. It's a large number of planes which they seemed to mostly use for recon - not that recon was unimportant - it was very important and recon planes seemed to almost always get shot down, so a fast one like the P-51 / A-36 certainly had an important role. I'm just wondering why they weren't using them more on fighter sweeps over German airfields like they did with the P-40s and Spit Vs.
We have been over this before, the P-47 had much greater endurance than Spitfire, roughly double on internal fuel.The Thunderbolt didn't want to climb or turn and had the endurance of a Spitfire.
Because the early Allison two stage was a piece of crap. Talking about the early test rig/s. You can "prioritize" whatever you want, without sufficient engineers and a good basic design you have crap for output. The first proposal/development contract was in Dec 1940 and used an auxiliary stage supercharger using the smae sized impeller as the main engine and used a fixed speed (single) supercharger drive to the auxiliary supercharger. At the time Allison was building about 250 engines a month and desperately trying to increase production of engines for P-38s, P-39s, P-40s (all different models) and work on a few other experimental projects. What gets DE-prioritized ? weight given is 1545lbs and output is whopping 1150hp at 21,000ft. I think we can see why they weren't jumping all over this thing.Why in the world didn't the AAF prioritize two stage Allison production for the P-39, P-40 and P-51? Turn these planes into high altitude planes and their utility to the AAF goes through the roof.
But the big question is why the AAF insisted on making the P-39, P-40 and P-51 so damn heavy when the engine they were designed around only produced 1150-1200HP at TO? At 6# per HP those planes should have weighed 7200# when they actually weighed 7650, 8400 and 8600#.
Either a two stage engine or a significant weight reduction program would have turned those planes into tigers.
A clean Thunderbolt (as all were until August '43) had barely the same range as a clean Spitfire especially in the ETO where they had to operate at max continuous.We have been over this before, the P-47 had much greater endurance than Spitfire, roughly double on internal fuel.
Because the early Allison two stage was a piece of crap. Talking about the early test rig/s. You can "prioritize" whatever you want, without sufficient engineers and a good basic design you have crap for output. The first proposal/development contract was in Dec 1940 and used an auxiliary stage supercharger using the smae sized impeller as the main engine and used a fixed speed (single) supercharger drive to the auxiliary supercharger. At the time Allison was building about 250 engines a month and desperately trying to increase production of engines for P-38s, P-39s, P-40s (all different models) and work on a few other experimental projects. What gets DE-prioritized ? weight given is 1545lbs and output is whopping 1150hp at 21,000ft. I think we can see why they weren't jumping all over this thing.
The F9R engine was proposed to the Navy with a weigh of 1510lbs and 1125hp at 18,000ft using a two stage supercharger.
In part because the US believed in self sealing tanks and pilot protection, in part because US strength standards were higher than some other countries and in part because the US was saddled with the .50 cal machine gun and it's ammo. A P-40D with four guns and 250rpg was carrying 621lbs of guns, ammo and gun equipement. A Spit with two 20mm and four .303s was carrying about 650lbs of guns/ammo, extra equipement unknown.
How much below four .50 cal do you want to go? Please note the Spit was carrying 243bs of ammo, 1000 rounds of .50 cal weighs 300lbs.
Yes the US planes were over armed but their is a limit as to how low you can go.
My guess on the P-51A / A-36 is that they didn't have too many of them in the Med or Italy and were probably using most of them for recon and "army cooperation" stuff from the UK.
A clean Thunderbolt (as all were until August '43) had barely the same range as a clean Spitfire especially in the ETO where they had to operate at max continuous.
Regarding the two stage Allison, 1180HP at 21500' was a tremendous increase over single stage models that would develop less than 700HP at that altitude. The Merlin 61 only developed 70HP more at 23000'.
While we are on the subject of superchargers, how did the Germans manage to get such good high altitude performance with the DB 601 series, just a lighter plane? Multi speeds? Something different about the impeller? I know water injection came a bit later (I think) and they didn't use two stage superchargers.
They used a variable speed drive for the supercharger, and improved the supercharger itself over time. The supercharger may have even got bigger in later versions.
I thought everyone knew that.