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The last 310 A-36 were apparently ordered by USAAF without dive brakes per the Wiki.
If you are wondering why Spitfires may not have the same range as some other aircraft types in spite of having a lot of fuel (as was speculated upon recently in this forum by Shortround though I can't remember if it was in this same thread)
The Spitfire certainly did not have "a lot of fuel".
Range was affected by drag, so would not fly as far as a P-51 on the same amount of fuel with the same engine.
Don't know. I'm not a Merlin ex-spurt, but from I've read here and about, I think it had something to do with the vibration levels becoming a problem at or below 1600 RPM and high MAP, such that it threatened bearing failure. Whether this was a matter of bearing design and manufacture, engine balancing, bending strength of various parts, uneven mixture distribution, or any of a whole host of other potential problems, is a drgondog question.Also, was it that the Merlin couldn't do it, or that it was rough doing it?
You missed the point here. 500 Apaches ordered, then 310 more, then 310 dive brakes and nose guns deleted, and; "Presto-Change-O", 310 P-51As miraculously appeared! Don't you just love that sleight of hand stuff?That would mean only190 A-36s were produced which is definitely wrong.
IMO, the primary deficiency of the Mustang I, IA, A-36 and P-51A in air to air combat from low level to 11-15K was the original aileron design combined with throw angles. The earlier Allison Mustang had +/-10 degree deflection. NACA and NAA improved the shape, sealed it to improve aero efficiency and increased the deflection angles for the P-51B-1. They were first tested on the NA-101 XP-51B.
The Brits achieved much better max HP by removing boost controls and as a result the Mustang I/IA were both faster and climbed about the same as the FW 190 and Bf 109 but they avoided engagement as much as possible
All of these were similarly limited in roll performance. All were at a disadvantage in turn if the first deployment of flaps didn't achieve the desired effect of achieving deflection, simply because the increased drag hurt the primary advantage of the very clean airframe.
Against the Ki 43, the A-36 and P-51A (and P-51B/C) were simply overmatched in low speed maneuvering flight, as ALL US fighters found themselves, at low altitude.
That said, the P-51A achieved better than parity perhaps because the original deployment of the A-36 to CBI proved the case - Do NOT engage in low and slow gunfight with Japanese a/c. the 311th FG (primary destination for CBI P-51A) produced several aces including England and Mulhollem obtained all of their victories in them before converting to P-51C. The 23rd FG also received P-51A but at a later stage and were first to get P-51B-1 in very late 1943. Tex Hiil nailed two in the P-51A for example.
All that said, consider that both P-47D and P-38J Fighter pilots relegated to low level CAS had very few aces despite flying an order of magnitude more missions in the ETO/MTO.
You tackle a complex evaluation, which as noted is not all about top speed or close in maneuver battles at low speed.To be clear, the reasons I bring all this up, are one to point out that the P-40 was indeed one of the more under estimated fighters in WW2 (and also the Ki-43 though I haven't gotten as deep into that deadly plane yet), but also to show what I think this fascinating deep dive into the early P-51 makes clear.
When evaluating fighters it's not sufficient to look at some basic numbers like top speed, firepower or range or what have you, you also need to look at the historical combat record. That in turn can help you find factors which can seem counter-intuitive, such as the subtle differences (like a relatively tiny adjustment to Aileron deflection angles, better ammunition or a new gun sight) which make an aircraft more suitable to achieve victory in a given Theater.
The recipe for victory is often reduced down to the obvious ones like speed and firepower. But sometimes, as with the Ki-43, or say, the Bf 109F, (comparatively) lightly armed planes with seemingly modest performance, proved to be some of the most effective war-machines of the war in terms of enemy aircraft destroyed.
In many cases, like with the B-239 or P-39, or the P-51, success seems to be a matter of developing suitable tactics and training for the enemy at hand, and finding both major (i.e. a new engine) and seemingly minor technical changes that are done as the result of early combat trials. Together technical modifications and training / tactics make the difference from poor or mediocre combat results to good or excellent ones. But of course this can take time, and how 'rough' the early combat debut of a fighter was has to do with how intense early combat experiences were before the bugs were worked out and the tactics optimized.
I.e. Allied planes which had their debut in 1940, 41 or the first half of 1942 may have faced a steeper and harsher learning curve (so to speak) than planes that rolled out in the second half of 1942 or later.
On the other hand perhaps this was an advantage that planes which were around from the beginning of the war and did get through that rough shakedown process, such as the Spitfire, Hurricane, Bf 109, A6M, Ki-43 or Yak 3 over some other later types which had to work out teething problems at a slower pace before they achieved excellence (like the P-51 or the Typhoon).
S
Very interesting post drgondog, much appreciated!
yeah you can't always use flaps in a turn for a variety of reasons, so turn was an issue too. i wonder if that was improved somewhat as well in later Mustang models?
Yes - because both Turn and Climb are intrinsically linked to Power Required and Power Available - and the 1650-3 and -7 were very powerful engines throughout the flight envelope. That said, most good pilots were aware of the significant and deleterious effect of flap deployment on drag and associated reduction in both speed and associated Energy.
That's interesting so there was in fact more than the one Allison P-51 Ace then? England and Mullhollem were P-51 aces? YES
P-40 squadrons with 23rd FG, 51st and 80th FG etc., did well against Ki-43 and other Japanese types like Ki-44. Aviation historian Robert Molesworth, not normally given to hyperbole, noted that "...the P-40 simply dominated the skies over Burma and China. They were able to establish air superiority over free China, northern Burma and the Assam valley of India in 1942, and they never relinquished it.". There were at least 70 P-40 Aces in the CBI and Pacific. According to a Thread I found on this forum, P-40s even did well against late model Japanese fighters like Ki 61 and Ki 84.
One of the tactics which developed for later model P-40s against Ki-43 or A6M was to extend in level flight, i.e. not by diving away, and then execute a sudden and very swift turn as soon as a certain distance was achieved and come back for a head-on attack. This technique, tested against a captured Zero as described in this War Dept memo (see page 7), is an example of something which may have been harder to do in an A-36 or P-51A given roll and turn rates.
The Mustang I and P-51A could both 'Extend in level flight' faster than the P-40E through N, and the actual turn rates of the P40 vs P-51A were very close. The Only advantage that P-40 had over contemporary P-51 was Roll. The INITIAL turn rate of the P-40 was slightly faster due to initial roll and lower W/L than P-51A, but the cleaner airframe of the P-51A along with same HP gave the Power Available to Power Req'd edge back to parity for the Mustang due to cleaner airframe (MUCH cleaner).
Another technique described by P-40 Ace Robert DeHaven was the "Low yo-yo" to out turn an A6M or Ki-43, which if I understand correctly requires both good roll and turn capabilities.
And a superior pilot.
And yet you had quite a few Aces in P-40s at low altitude in the Med. At least 46 Commonwealth Aces and 14 USAAF, not to mention 45 in the CBI where they also did primarily FB sorties.
DAF squadrons flew a mix of missions but certain subtypes, like the P-40K, did mostly fighter-bomber sorties, and yet they scored many air to air victories.
Look to both Production comparisons, number of squadrons ushered into combat, length of time in combat operations. The P-51A and A-36 deployment was miniscule. The A-36 was replaced by P-40 and then P-47 because only 500 were ever built. The 27th and 81st FG hated to see the A-36 phased out in MTO but they accounted for over 40% of the production actually reaching combat ops.
Neither P-47 nor P-38 excel at low altitude, it's worth noting, in spite of the fact that they were often given such missions.
S
Like the A-36 and P-51A and F4F and P-40 and P-39 - the AAF and Commonwealth 'made do' with what they had. There is a reason that P-51B/D destroyed more than any Commonwealth or US fighter by a significant total.
P-51B would also have been late for Darwin.
The first production P-51B flew in May 1943.
Like the A-36 and P-51A and F4F and P-40 and P-39 - the AAF and Commonwealth 'made do' with what they had. There is a reason that P-51B/D destroyed more than any Commonwealth or US fighter by a significant total.
The first P-51Bs didn't arrive in Europe til late 1943.