An Allison V-1710 with a two-speed supercharger in 1942 (6 Viewers)

[Steamed_Banana]

Yes and the converse is true regarding Axis claims.

Prove it. Let me know when you have the victory credits awarded, and the MACRs in hand to analyze the losses. Are you also stating that the 31st and 52nd flying Spitfires in 1943 were below he P-40 units?

I would say that while there was some variation, outcomes were about equal between 31st and 52nd vs most of the P-40F/L groups, with a slight edge to the Spitfire units. I will be glad to show some operational history examples so we can look at real numbers, as I did in the P-38 thread, but it will take a little time. I can show some examples of combat from the CBI as well..

Total victory claims for USAAF FG with P-40F/Ls (in reverse order highest to lowest):

57nd FG - 144 victories from Aug 42 - Jan 44 (6 aces flying P-40s)
33rd FG - 137 victories from Nov 42 - Feb 44 (3 aces fling P-40s)
325th FG - 133 victories from Apr 43 - Oct 43 (4 aces flying P-40s)
79th FG - 118 victories from Dec 42 - Mar 44 (2 aces flying P-40s)
324th FG- 66 victories from Mar 43 - Jul 44 (3 Aces flying P-40s)

99th FS (Tuskegee) also had 19 victories while flying P-40s from June 1943-June 1944.

I don't have losses for all of these, but for example 325th lost a total of 32 in combat and 43 total out of 3990 sorties. Of the 5 US fighter groups flying P-40s, 33rd FG had the most losses, mainly in Jan and Feb 1943.

Most of these victories for all five groups were between Nov 42 and Aug 43, mainly over North Africa, with some units also the Sicilian and Italian campaigns through Anzio. The second date indicates when these units transitioned to either P-47 or P-51. The P-40 was used a lot as a fighter-bomber, more than any other Allied type in Theater except the P-47. All of these units also flew a lot of fighter-bomber missions, on average about 50%, the rest being escort for light/medium bombers (or other fighter bombers), CAP, or fighter sweeps. The exception is 324th FG which flew almost exclusively fighter-bomber missions. Most of their victories were against fighters, for example 325th FG claimed 95 Bf 109 and 26 MC 202 out of a total of 133 victories in the P-40s.

A total of 23 US pilots made ace while flying P-40s in the MTO


Total victory claims for USAAF FG with Spitfire V and IX

31 FG had 61 victory claims in North Africa through May 1943, and a total of 194 victories with Spitfires all together.
52nd FG claimed 86 victories in North Africa through May 1943, and a total of 152 while flying Spitfires all together.

Most of the Spitfire units missions were CAP, fighter sweep, or short range escort. Google says 13 US pilots made ace while flying Spitfires in the MTO


Total victory claims for USAAF FG with P-38F/G
14th FG claimed 36 victories before being transferred out of the theater in early 1943
82nd FG claimed 150 victories during the North African campaign, and 500 in total.
1st FG also claimed 151 victories during the North African campaign.

By Feb 1943 the P-38 units were mostly flying longer-ranged bomber escort missions into Italy. Google says there were 17 US pilots flying P-38s who made Ace in the MTO.
15th AF records state 514 P-38s were lost in the MTO.

A few more stats:

598 (some say 592) US victories claimed by 5 x US P-40 FG in the MTO, 321 of which were for BF 109s. RAF Kittyhawk units claimed 450. (total US+British = 1042)
1431 US victories claimed by the 3 P-38 FG in the MTO (most of these were over Italy from 1944) (another source says 608)
364 US victories claimed by the 2 US Spitfire FG in the MTO
263 victories claimed by US units flying P-47s in the MTO
1063 victories claimed by US P-51 units in the MTO (these are mostly 1944-45, and it includes all P-51 victories)
26 victories claimed by USN F4F units in the MTO (I believe these were all against Vichy French aircraft during Torch)
25 victories claimed by US Beaufighter units in the MTO
There were also 25 claims by P-39 units
I coldn't find the total for the A-36
Luftwaffe Claims (5 x JG): 1,118 RAF & USAAF P-40s (486 before US arrival)
Luftwaffe lost 711 aircraft in 1943, 246 fighters (13% of German global fighter inventory)

Pilots and tactics adapted to force tendency to 'dogfight'.

I concede that this is possible for certain units, like the Air Commando group, but it seems less likely for 23rd and 51st FG which (I believe) also operated P-51A and had a lot of experience in Theater.

Again, and I respect Shores, show me the receipts including MACR's highlighting specific losses to Ki-43s.

I can show you what Shores lists in "Bloody Shambles" volume 3, when I have time to transcribe some pages.

 

[Steamed_Banana]

I would say in air combat, the P-40F/L was equivalent to the Spitfire V, but it had longer range (and was better as a fighter-bomber)
P-40F/L was markedly superior to the Allison P-40s in combat against Bf 109G and later, and vastly so compared to the Hurricane II
The Spit IX and VIII on the other hand were markedly superior to any P-40 variant.
P-51B/C/D was also clearly superior to any P-40 across the board.
P-40F/L did about the same as the P-47 in Theater.
Victory to loss ratio is (I think) a bit better for P-40F/L in air to air combat than the P-38 during 1943, in spite of the P-38 units having more 'confirmed' victory claims, they also took more losses.


I think the A-36 did well in it's fighter-bomber role, it was almost unique in it's ability to penetrate dangerous airspace and score hits. Better than the P-40 (as a fighter bomber) in that sense.

 

[wuzak]

598 (some say 592) US victories claimed by 5 x US P-40 FG in the MTO
364 US victories claimed by the 2 US Spitfire FG in the MTO

119.6 (118.4) victories per US P-40 FG in MTO.
182 victories per US Spitfire FG in MTO.

Does that mean Spitfire groups were 50% more effective?

 

[wuzak]

Smithsonian have these in their catalog record. Some may find of interest.
View attachment 877208

Dan Whitney's Vees for Victory references a test of the Merlin 2 stage supercharger with the V-1710.

IIRC, the result was almost identical power from the V-1710 as the Merlin.

 

[Steamed_Banana]

119.6 (118.4) victories per US P-40 FG in MTO.
182 victories per US Spitfire FG in MTO.

Does that mean Spitfire groups were 50% more effective?

Well, you could look at it that way, but you can look at it a lot of different ways.

The Spitfire totals are for a longer period of time, and also represent two or more types, Spit V and Spit IX. 31st FG also had some Spitfire Mk VIII.

But even with these excellent fighters, during the period of the most air to air combat, some of those P-40 fighter groups hold up very well. Compare for example, 325th FG with 133 victories in seven months (April-Oct 1943), vs 31 FG with 61 victory claims in the same time period of seven months (November 42-May 1943) and 52nd FG with 86 victories in North Africa during about 9 months (Sept 42 through May 1943). So by that reckoning alone I'd say 325th FG looks a bit scarier for the Germans.

Of course, this just gives us the broadest strokes. You can't really make sense of it with just this amount of data. Evaluating the operational history depends on the missions flown, the loss rates, the actual enemy losses (as opposed to just claims). The amount of enemy contact they had. Those Spitfire units were not always in combat, the P-40 units were often flying fighter-bomber strikes where they didn't fight enemy fighters as much.

IMO (for what little that is worth) as I said, the P-40F/L was basically equivalent to the Spit V in fighter vs fighter combat, but it had about 50% better range (depending on the precise configuration) and was more useful as a fighter bomber. The Spit IX was clearly superior to any P-40 variant (and a real threat for any Axis fighter), though it still had the short range. The Spit VIII was just as superior as the Spit IX (or more so) but had almost the same range as the P-40.

But veering back to the thread topic, it is clear to me that the two speed Merlin engined P-40s were quite effective in this Theater, and they were in the Pacific too even though there were fewer of them. More P-40s with two speed engines would have been very useful. I suspect P-39s would have been a lot more useful too. As would NA 73 / P-51A type early Mustangs, though i don't know if timelines fit.

For that matter, converting Spit Vs to use a Merlin XX or equivalent also seems like a winning idea, though I gather there were some 'fit' issues with the engine mounting etc. I think Spit V with Merlin XX is a lot more useful than Hurricane II with Merlin XX (or two speed V-1710).

A two speed supercharged V-1710 might have helped with some of the early P-38 issues too, though it seems that historically by the second half of 1943 the P-38 units were holding their own fairly well too, getting close to 1:1 outcomes at least.

When the 5 US fighter groups flying P-40s converted to P-47s they didn't do all that much better in air to air combat. Of course the early P-47s had some issues compared to later versions.

 

[Engineman]

Dan Whitney's Vees for Victory references a test of the Merlin 2 stage supercharger with the V-1710.

IIRC, the result was almost identical power from the V-1710 as the Merlin.

I will have a read of that!
But, just straight-off the bat, it is not surprising given the basic similarity in the two types. I presume here that the usual V-1710 supercharger was removed and the RR 2-stage did all the supercharge.

Eng

 

[MiTasol]

For that matter, converting Spit Vs to use a Merlin XX or equivalent also seems like a winning idea, though I gather there were some 'fit' issues with the engine mounting etc. I think Spit V with Merlin XX is a lot more useful than Hurricane II with Merlin XX (or two speed V-1710).

I think you will find they did a lot of those conversions and called them Mk IX.

 

[wuzak]

I think you will find they did a lot of those conversions and called them Mk IX.

Mk IX was Merlin 60 series conversion - 2 stage, 2 speed.

Mk.III was the prototype with the Merlin XX with 2 speed single stage supercharger.

 

[MiTasol]

Mk IX was Merlin 60 series conversion - 2 stage, 2 speed.

Mk.III was the prototype with the Merlin XX with 2 speed single stage supercharger.

Thank you

I stand corrected.

 

[wuzak]

I will have a read of that!
But, just straight-off the bat, it is not surprising given the basic similarity in the two types. I presume here that the usual V-1710 supercharger was removed and the RR 2-stage did all the supercharge.

Eng

The Rolls-Royce supercharger did all the supercharging, the Allison on being removed or disconnected.

The Rolls-Royce supercharger could not be quickly modified to fit to the Allison, so it was separate and, presumably, driven by another engine.

 

[wuzak]

But even with these excellent fighters, during the period of the most air to air combat, some of those P-40 fighter groups hold up very well. Compare for example, 325th FG with 133 victories in seven months (April-Oct 1943), vs 31 FG with 61 victory claims in the same time period of seven months (November 42-May 1943) and 52nd FG with 86 victories in North Africa during about 9 months (Sept 42 through May 1943). So by that reckoning alone I'd say 325th FG looks a bit scarier for the Germans.

You're still not comparing them at the same time.

The amount of opportunity for the FGs may be completely different.

 

[MiTasol]

The Rolls-Royce supercharger did all the supercharging, the Allison on being removed or disconnected.

The Rolls-Royce supercharger could not be quickly modified to fit to the Allison, so it was separate and, presumably, driven by another engine.

Driving the RR blower with another engine would defeat the purpose to a very large extent as the power to drive the supercharger would have to be calculated/measured and subtracted from the engine output power. I am sure that report covers the whole installation. I am surprised that WJPearce at Old Machine Press has not done an article on this report as he loves investigating oddball engines.

I would suspect the Allison supercharger was disconnected (removing the impeller itself will do that) and the RR supercharger then driven similar to the way the ASB was driven on the ASB Allison's which would have been in development about that time. Due to the large HP required to drive any supercharger any other shafts (like the generator drive) would not have been adequate. The camshaft and generator etc drives are not shown on the second diagram but basically remained unchanged.

The RR discharge would then be connected straight to the normal induction system.

 

[Engineman]

The Rolls-Royce supercharger did all the supercharging, the Allison on being removed or disconnected.

The Rolls-Royce supercharger could not be quickly modified to fit to the Allison, so it was separate and, presumably, driven by another engine.

So, this is mentioned on page 333 of the Vee book, a Wright Field engineering V-1710-91 lash-up with a remote mounted Packard V-1650-3 supercharger and intercooler (aftercooler).
The results were that a very similar FTH and power output was achieved, which must have been taking account of the supercharger power consumption.
The quote says little more, other than the testing consumed 3 of the RR-type superchargers, apparently because the engineers did not get the heating/cooling of the supercharger bearings and housings correctly balanced. This requirement is hinted at by the careful arrangement of coolant passages in the casing of the RR 2-Stage S/C.

Eng

 

[Steamed_Banana]

You're still not comparing them at the same time.

The amount of opportunity for the FGs may be completely different.

Yes, I agree, in fact I believe I pointed that out in my last post. The quality of the opposition in terms of training was also changing, and very likely not as good by the second half of 1943.

You can only get a very 'broad strokes' idea of it based on this limited data.

 

[Shortround6]

Yes, I agree, in fact I believe I pointed that out in my last post. The quality of the opposition in terms of training was also changing, and very likely not as good by the second half of 1943.

You can only get a very 'broad strokes' idea of it based on this limited data.

And that is why trying to compare the combat record of the 225 P-51A's Built as fighters (Number deployed overseas???) and used by the US compared to the 1902-1911 P-40F and Ls built (many of which went to the British0 and several hundred stayed in the US as trainers needs a very careful analysis as to numbers of combat missions flown, what types of missions, numbers of aircraft involved and numbers of enemy aircraft encountered. And that does not include training and experience of the Allied Forces and Enemy forces.
Records do not even agree as to the number of P-40Fs built.

The Tuskegee Airmen are supposed to have had P-40L-1s when they arrived in North Africa in late June of 1943. Most L-1s were known as the "Gypsy Rose Lee" version after the famous stripper. Only four .50 cal guns, Ammo reduced to 201 rpg, Forward wing tank taken out, some armor removed and a few pieces of equipment removed for weight reduction.
How much "stuff" got put back in once they were in combat is subject to question. P-40L-1s were supposed to be about 400lbs lighter than a P-40F with 6 guns with 120 gal of fuel in both. There both long and short fuselage P-40Fs and P-40Ls built but only the first 50 P-40Ls had the short fuselages, they may have been the only ones with 6 guns.
To show the confusion in numbers, just about 100 Merlin powered P-40s were repowered with Allison engines when their engines needed overhaul/replacement. These were all done to US based (trainer) aircraft. It is possible that some overseas aircraft were converted but the records of such aircraft don't exist (?).
For the P-40F, out of the first production order (903) at least 76 were wrecked during training and a further 36 were downgraded to instructional airframes (non-flying).

It seems that at least 58 P-40Fs (first batch) were sent to the Pacific (Hawaii) with 6 different ultimate destinations.
30 (?) from the second batch were sent to the Pacific (New Caledonia) with 9 sent on to Guadalcanal. 2 of the first batch wound up at Guadalcanal.
Others (?) that might have transferred in and not recorded?

The US tried to record fates on Aircraft Record Cards which can include Flak, Enemy action (air combat) and Missing in Action. Also crashes/accidents or written off for other reasons.
These records may not agree with unit records which were thousands of miles away.

 

[Steamed_Banana]

And that is why trying to compare the combat record of the 225 P-51A's Built as fighters (Number deployed overseas???) and used by the US compared to the 1902-1911 P-40F and Ls built (many of which went to the British0 and several hundred stayed in the US as trainers needs a very careful analysis as to numbers of combat missions flown, what types of missions, numbers of aircraft involved and numbers of enemy aircraft encountered. And that does not include training and experience of the Allied Forces and Enemy forces.
Records do not even agree as to the number of P-40Fs built.

It is complex, and I agree confusing, but it looks like about ~1200-1300 F and ~700 L were built. I don't think several hundred made it to the British, who used them in only two squadrons (260 RAF and 3 RAAF), of which only one (3 RAAF) kept them for a really long time, due to both shortages of engines and airframes.

The engine problem as I think you know was apparently partly solved in the Middle East by the British sourcing some Merlin XX and associated spare parts.

I suspect the exact number used by the British is somewhat obfuscated or de-emphasized historically because it was a bone of contention during the war. The British liked the Kittyhawk for North Africa and apparently built their strategy around it to a large extent, but were frustrated by the altitude limitations of the V-1710. They suggested using the Merlin XX, to which suggestion the US finally agreed and it was finally done, but then the US took most of the Merlin P-40s for themselves.

The Tuskegee Airmen are supposed to have had P-40L-1s when they arrived in North Africa in late June of 1943. Most L-1s were known as the "Gypsy Rose Lee" version after the famous stripper. Only four .50 cal guns, Ammo reduced to 201 rpg, Forward wing tank taken out, some armor removed and a few pieces of equipment removed for weight reduction.

The 99th FS (Tuskeegee) flew P-40L for one year, between June 43 and June 44, and claimed 17 victories during that time.

In addition to this and the two British squadrons, the Free French GC II/5 (two squadrons) flew P-40F or L from July-Sept 1943, claiming 8 victories.

How much "stuff" got put back in once they were in combat is subject to question. P-40L-1s were supposed to be about 400lbs lighter than a P-40F with 6 guns with 120 gal of fuel in both. There both long and short fuselage P-40Fs and P-40Ls built but only the first 50 P-40Ls had the short fuselages, they may have been the only ones with 6 guns.

Most of the lightening steps done to the P-40L were simply established field mods to P-40F which were done in the factory for convenience. They could all be undone, from what I understand. The guns in particular were changed depending on the types of missions flown - for strafing 6 guns were preferred, for fighter vs fighter combat, 4 guns were preferred by some units (not all). They didn't change these mission to mission but they might spend 3 or 4 months flying mostly strafing / fighter bombing missions and then spend 3-6 months flying escort missions, which may result in changes. Fuel capacity also varied depending on how far away they were typically flying.

The same was also done in the field with P-40E, K, M, and N types, by US and Allied units, going all the way back to Java and continuing to the end of the war.

To show the confusion in numbers, just about 100 Merlin powered P-40s were repowered with Allison engines when their engines needed overhaul/replacement. These were all done to US based (trainer) aircraft. It is possible that some overseas aircraft were converted but the records of such aircraft don't exist (?).

The Allison conversions were designated as P-40R, it looks like 70 were converted, all back in the US and used for training as you noted.

For the P-40F, out of the first production order (903) at least 76 were wrecked during training and a further 36 were downgraded to instructional airframes (non-flying).

It seems that at least 58 P-40Fs (first batch) were sent to the Pacific (Hawaii) with 6 different ultimate destinations.
30 (?) from the second batch were sent to the Pacific (New Caledonia) with 9 sent on to Guadalcanal. 2 of the first batch wound up at Guadalcanal.
Others (?) that might have transferred in and not recorded?

The Pacific use is a bit of a mystery for me so far. Enough were sent to fully equip the elite 44th FS for about 6 months, after which they were replaced by P-40M. There appears to have been at least one other unit flying P-40F/L in the Pacific but I haven't been able to nail it down yet.

The US tried to record fates on Aircraft Record Cards which can include Flak, Enemy action (air combat) and Missing in Action. Also crashes/accidents or written off for other reasons.
These records may not agree with unit records which were thousands of miles away.

I'm trusting Shores research here, at least provisionally, to give us a reasonably accurate look at these loss numbers. I don't even try to estimate loss type in any serious way, because we don't know what the losses were caused by because fairly often the units themselves didn't know. Many were just missing or 'FTR'. But we can see that losses took place at the same time and place as (or after) combat, which definitely tells us something.

And indeed, knowing the operational history, as you are alluding, is difficult and cannot be ascertained with the certain accuracy of a time-machine / video camera, but the same can be said for much more concrete and prosaic numbers, like for example speed.

What was the true top speed of a P-40F or L with field equipment and using whatever engine settings and fuel, tropical filters etc. they used in combat missions, and including bomb shackles, radio direction transponders, and other drag inducing additions. And including drag alleviation such as by filling holes, sanding, waxing, etc. which was also done by some units when they had time. I have seen anywhere from 350-375 mph from tests.

What was the true top speed of the P-39 in field conditions? How about the Spitfire V (Trop)? Bf 109F (Trop) or G2 or G4 or G6 (Trop)? MC 202 and 205? P-51A?

We get a range of numbers and have to guess which is accurate. But we can still obviously make provisional estimates and use that as a basis to try to gain a sense of what was really going on. These estimates change as more data emerges.

 

[Frog]

P-40 from the 110th Tactical Reconnaissance Squadron - South Pacific (from a Missouri ANG publication).

 

[Shortround6]

It is complex, and I agree confusing, but it looks like about ~1200-1300 F and ~700 L were built. I don't think several hundred made it to the British, who used them in only two squadrons (260 RAF and 3 RAAF), of which only one (3 RAAF) kept them for a really long time, due to both shortages of engines and airframes.

The engine problem as I think you know was apparently partly solved in the Middle East by the British sourcing some Merlin XX and associated spare parts.

I suspect the exact number used by the British is somewhat obfuscated or de-emphasized historically because it was a bone of contention during the war. The British liked the Kittyhawk for North Africa and apparently built their strategy around it to a large extent, but were frustrated by the altitude limitations of the V-1710. They suggested using the Merlin XX, to which suggestion the US finally agreed and it was finally done, but then the US took most of the Merlin P-40s for themselves.

British use is obscured because they used the name KittiHawk II for both P-40Fs and P-40Ls and Kittihawk III for both P-40Ks (small number) and P-40Ms.
The British were only supposed to get 6000 out of the first 9000 engines that Packard built. What they did with them was up to them. The US was supposed to get the other 3000 engines. Not saying that allocations could not be changed at times but the allocations had been made before the first engines rolled off the Packard line. First XP-40F used an imported RR built engine.
I am sure there were disagreements but the British paid cash for the Kittihawk Is and got 1500 Kittihawk IAs (P-40Es) lend lease.
Planning/procurement was zigging and zagging in 1942. The order for 600 P-40Ks had been placed on Oct 30th 1941. the order for another 700 P-40Ks was placed on June 11th 1942, along with some P-40Ls and P-40Ms to make up for the cancelation of the P-60 program. Curtiss had gotten a contract for 1950 P-60As on Oct 30th 1941 using a turbo Allison V-1710-75 engine. The XP-40F had flown June 30th 1941, 4 months before. I can't find the contract date at the moment but the first production plane with Packard engine flew in Jan 1942. With the cancelation of the turbo P-60A in the spring of 1942 the US was in a bind. The P-39 was not working as hoped for, the P-47 was running months late, The P-38 was not being built in large numbers and the P-51 was pretty much unwanted (soon to change very soon) which left the US Army very short of high altitude fighters, counting a a single stage Merlin as high altitude. Giving hundreds more Packard Merlin's to the British in the summer of 1942 was probably not going to happen.

In addition to this and the two British squadrons, the Free French GC II/5 (two squadrons) flew P-40F or L from July-Sept 1943, claiming 8 victories.

The French got a lot of P-40s in 1943 and early 1944, but they got them in dribs and drabs and since a lot of the first issue P-40s they got were first issue to them but actually used aircraft (well used) they needed a lot of replacements to keep even a few squadrons up to strength.

The Allison conversions were designated as P-40R, it looks like 70 were converted, all back in the US and used for training as you noted.

Curtiss records say just about 100 plans, pretty much an even divide between the Fs and Ls. The Curtiss Fighter Aircraft book (Dean & Hagedorn) has serial numbers broken down by air stations or organizations. Anywhere from 1 aircraft to 21 per organization. At least 3 of the planes had been returned from overseas.

The Pacific use is a bit of a mystery for me so far. Enough were sent to fully equip the elite 44th FS for about 6 months, after which they were replaced by P-40M. There appears to have been at least one other unit flying P-40F/L in the Pacific but I haven't been able to nail it down yet.

It may take quite a bit of research. Some may have stayed in Hawaii for local defense and even some of the planes that went to other places in the Pacific seemed to have disappeared.
At least 7 (?) went to the Southwest Pacific area with not mention (in the book) as to final destination or unit.
there were a lot of code names used for shipping destinations.
Iron and Maestro = Hawaii
Epic (or Poppy) = Noumea, New Caledonia
Bevy = Guadalcanal
Acid (or Roses) = Southwest Pacific area
Some planes went to one destination and then on to another. Now try to figure out which front line airfields got them?

What was the true top speed of the P-39 in field conditions?

Speed may have been as good or a bit better than the P-40s, unfortunately it didn't climb quite as well or had trouble at altitude due the smaller wing (or less lift)?
Also it lacked fuel. A P-39 with full internal fuel held about as much fuel as a P-40 did with the forward tank taken out.
P-39 didn't have a lot to take out. Taking out the four .30 cal guns and 1200rounds of ammo (forget the 1000rpg nonsense) only lightens the plane by
around 140lbs, taking out a pair of .50s and their ammo lightens the P-40 by about 290lbs.
Cutting the fuel to 87 US gallons makes a Hurricane look like a tanker.

 

[Steamed_Banana]

P-40 from the 10th Tactical Reconnaissance Squadron - South Pacific (from a Missouri ANG publication).

View attachment 877758
View attachment 877759

That appears to be an Allison engined P-40 due to the scoop on top of the nose

 

[Steamed_Banana]

British use is obscured because they used the name KittiHawk II for both P-40Fs and P-40Ls and Kittihawk III for both P-40Ks (small number) and P-40Ms.

They designated P-40F and L as II and IIa, but this seems to have corresponded with the length (long tail vs short)

The British were only supposed to get 6000 out of the first 9000 engines that Packard built. What they did with them was up to them. The US was supposed to get the other 3000 engines. Not saying that allocations could not be changed at times but the allocations had been made before the first engines rolled off the Packard line. First XP-40F used an imported RR built engine.

What actually happened to the 6000 British Packard V-1650-1 is another thing worth delving into vis a vis this thread. That could have been 4,000 more P-40Ls or Spit III or P-39 XX or P-51A XX or what have you right there. As far as I can tell, most of these engines seemed to end up in Canadian made aircraft which either didn't see action, or when they did finally get shipped over the UK, had their engines replaced. So it seems like a huge waste.

I am sure there were disagreements but the British paid cash for the Kittihawk Is and got 1500 Kittihawk IAs (P-40Es) lend lease.

They got a lot of them. They still wanted more, and as we know, planes that could fight effectively above 12-16,000 ft were very much desired!

Planning/procurement was zigging and zagging in 1942. The order for 600 P-40Ks had been placed on Oct 30th 1941. the order for another 700 P-40Ks was placed on June 11th 1942, along with some P-40Ls and P-40Ms to make up for the cancelation of the P-60 program. Curtiss had gotten a contract for 1950 P-60As on Oct 30th 1941 using a turbo Allison V-1710-75 engine. The XP-40F had flown June 30th 1941, 4 months before. I can't find the contract date at the moment but the first production plane with Packard engine flew in Jan 1942. With the cancelation of the turbo P-60A in the spring of 1942 the US was in a bind.

Interesting point about the anticipated P-60

The P-39 was not working as hoped for, the P-47 was running months late, The P-38 was not being built in large numbers and the P-51 was pretty much unwanted (soon to change very soon) which left the US Army very short of high altitude fighters, counting a a single stage Merlin as high altitude. Giving hundreds more Packard Merlin's to the British in the summer of 1942 was probably not going to happen.

We can maybe say medium high or middling altitude

The French got a lot of P-40s in 1943 and early 1944, but they got them in dribs and drabs and since a lot of the first issue P-40s they got were first issue to them but actually used aircraft (well used) they needed a lot of replacements to keep even a few squadrons up to strength.

This is what I used to think until pretty recently, but I found out that the P-40s which were presented to GC II/5 "Lafayette" in early 1943 were apparently brand new to the Theater P-40Ls, very much in demand by both US and British units. The deal was controversial (very shortly after this unit was in combat against the US and British forces during Torch) and was arranged by Colonel Harold Willis - they upgraded from Hawk 75s.

Curtiss records say just about 100 plans, pretty much an even divide between the Fs and Ls. The Curtiss Fighter Aircraft book (Dean & Hagedorn) has serial numbers broken down by air stations or organizations. Anywhere from 1 aircraft to 21 per organization. At least 3 of the planes had been returned from overseas.

It may take quite a bit of research. Some may have stayed in Hawaii for local defense and even some of the planes that went to other places in the Pacific seemed to have disappeared.
At least 7 (?) went to the Southwest Pacific area with not mention (in the book) as to final destination or unit.
there were a lot of code names used for shipping destinations.
Iron and Maestro = Hawaii
Epic (or Poppy) = Noumea, New Caledonia
Bevy = Guadalcanal
Acid (or Roses) = Southwest Pacific area
Some planes went to one destination and then on to another. Now try to figure out which front line airfields got them?

These are 44th FS in Guadalcanal ... these were holding the line quite well when the early F4U and P-38 were still struggling a bit in this area

Second from the front is White 111, aka the famous "Destitute Prostitute" flown by Jack Bade.

These are also 44th FS from Guadalcanal / "Cactus"

There were some others active in the Solomons. In one of his Pacific War books Claringbould mentions 6 which crash-landed on New Guinea after getting lost which were from another unit. I need to track that book down and find the reference he probably mentions the unit.

Speed may have been as good or a bit better than the P-40s, unfortunately it didn't climb quite as well or had trouble at altitude due the smaller wing (or less lift)?

Been wondering about that (smaller wings at altitude thing) myself. But a more potent engine might correct that I think?

Also it lacked fuel. A P-39 with full internal fuel held about as much fuel as a P-40 did with the forward tank taken out.
P-39 didn't have a lot to take out. Taking out the four .30 cal guns and 1200rounds of ammo (forget the 1000rpg nonsense) only lightens the plane by
around 140lbs, taking out a pair of .50s and their ammo lightens the P-40 by about 290lbs.
Cutting the fuel to 87 US gallons makes a Hurricane look like a tanker.

Yes agreed