Spitfire Combat Radius (range) evolution, limitations?

[GregP]

Hi Zipper.

There was a war on and taking a working Spitfire (or anything else) from the front line to fit a new fin and rudder or to recontour an elevator or stabilizer, etc. likely wasn't high on the priority list. Sure, they COULD have been modified, but they were flying and fighting at the time and changes were generally cut in at some point and not always retrofitted. Things like the dorsal fins fitted to P-51D and some B/C models as well as dorsal fins for P-47s WERE sometimes field-fitted, as were things like P-38 dive flaps.

Here's a good study of four P-51Ds. Only one, the 2nd one, has the dorsal fin extension:

So, the dorsal fun mod was either field-installed or the change was cut in somewhere between 44-1310 and 44-13926 (the two serial numbers of the nearest two). I'd have to look that up to be sure which. Somewhat obviously, these are early D models.

Here's a 2-seat TR IX in formation with an XIV. Note the different vertical tails since the Griffon had quite a bit more horsepower. The XIV has more chord, for sure, and a bigger fin:

 

[Wild_Bill_Kelso]

Giving that one a like just for the photos. That XIV is some sexy...

 

[GregP]

I was looking for my book on the 23rd Fighter Group, which I failed to locate, but i did find the 2012 Osprey "Air Vanguard' book "Allison Engined P-51 Mustang" by Martyn Chorlton. There are a few interesting tidbits of operational history in there, which I'll repeat here in no particular order

*During the Dieppe raid RAF Mustangs (I believe it says RCAF 400 Sqn) claimed a Fw 190 destroyed. They also comprised 11 of the 119 RAF aircraft lost that day, from 26, 239, 400 and 414 sqds. I didn't see any other claims.
*On Oct 22 1942 RAF Mustang Mk1 and 1As escorted Wellington bombers on a raid into Germany - against Dortmund and Essen. The raid was considered a partial success though the targets were obscured by clouds. All the aircraft returned to base. [It's unclear to me why they didn't do more of these escorted raids.]
*An RAF mission on June 29, 1943, a pair of Mustangs (one I and one IA) flown by Archibald MacLachlan and Geoffrey Page (the former flying with a prosthetic arm) flew a daylight raid all the way to Paris. They destroyed six enemy aircraft (four HS 126s and two Ju 88s).
*Twenty three (23) RAF Squadrons were equipped with Allison Mustangs (Mks I and IA)
*On June 6 1944 three RAF Mustangs were active over the D-Day beach, two flying cover for a Tac-R fighter, when they were attacked by four plus then another two FW 190s. One Mustang was destroyed and the other two managed to disengage. Three Mustangs were lost that day in total out of 86 Tac-R and spotting sorties.
*A-36 aircraft flew 23,000 sorties and claimed 86 enemy aircraft in combat (this would be both in USAAF service both in China / India and the MTO)
*311 FBG based in India attempted to use A-36 as transport and bomber-escort but found that (this is a direct quote from the Osprey book) "the deficiencies of the A-36 in one-on-one aerial combat were soon highlighted. On one of the early sorties to provide fighter protection for a formation of C-47s flying from India to China, three A-36s were lost, presumed shot down."
*This unit flew both A-36 and P-51A. Both types were used for transport and fighter escort.
*Operations with P-51A began in Oct 1943 for both 23rd FG and 311 FBG
*On Oct 18 1943, P-51A of the 530 FS, 311 FG flew escorts for B-25s in a raid against Rangoon. This was a 450 mile trip coming from Kurmitola, India, the P-51A were using two 75 gallon drop tanks. They were attacked by four Ki-43 from the 64th Sentai, 2nd Chutai based out of Mingaladon. Quoting from the Osprey book: "A frantic low-level combat ensued at very low altitude, resulting in two Mustangs being shot down." There were no claims against the Japanese.
*A second raid (no date given) to Insein in Burma resulted in the Mustangs being bounced by Ki-43s from the 64th Sentai again, one mustang shot down in the initial bounce, then 3 more including the 311 FG CO, Colonely Harry Mehon. One Ki-43 was shot down and another made a forced landing.
*On Dec 1, 1943 31 FBG escorted B-24s to Rangoon. Mustangs were bounced again and one was shot down by a Ki-43, another ran out of fuel and crashed on the return trip.
*Feb 14 1944, 1st Air Command Group (ACG) under Philip Cochran (with 30 x P-51As) escorted a formation of B-25s against Zaundaing. They were bounced by Ki-43s of the 50th Sentai while strafing the target. Two Mustangs were shot down and three more damaged, for no claims.
*ACG 1 had a successful raid from forward Burmese base at Chowringee" (no date given) against the bases at Shwebo and Onbauk with "several" Ki-43s claimed shot down and "more than 30" on the ground for no losses.
*On March 16, 1944 however the same unit was bounced by 50th Sentai and 3 x Mustangs were shot down, with no claims against the Japanese.
*On April 4, 1944 1st ACG encountered 50th Sentai again and "enjoyed complete success", resulting in 50th Sentai being moved to Saigon for a refit. No figures for claims / losses are given here.

These were all the specific combat actions I could find in the book though I might have missed a couple. Now I can compare these actions to those of various P-51 (Merlin), P-40, P-38 and Spitfire units in the Theater and I can promise you they did better, at least in terms of claims made. Hurricanes did not do so well in the CBI and were probably worse than the P-51A / A-36. These are from Osprey books so fairly little effort is made to verify the claims via Axis records. Maybe Bloody Shambles provides a more accurate picture I don't have that book yet.

Overall though, I cannot escape the impression that the Allison Mustang did not reach it's full potential here as a fighter.

You can find many different reports. Usually, when someone was attacked, the attackers had the upper hand by virtue of diving from above or from the sun, or whatever. Find the reports when the P-51A did the attacking and you will find the encounters where the P-5A had the advantage. It DID reach its potential, but the 2-stage Merlin-powered version was produced in WAY higher numbers, flew higher and faster, and got the bulk of the missions where victories over attacking enemy fighters were likely to happen.

Kelso, you are completely free to feel the P-51 wasn't a good fighter and nobody will obviously be able to change your mind. Perhaps we should not try since everyone has an opinion backed by whatever facts they have dug out over the years. You won't likely change anyone else's opinion, either. It's all good. The war is long over, and discussion of the merits of the various aircraft makes these things interesting.

I've sat through maybe a couple of hundred talks with WWII fighter pilots. Almost every single one of them felt the aircraft they were assigned to fly was the best fighter in the world, regardless of which one they flew. Most only flew ONE fighter, so you can draw your own conclusion from that.

Cheers.

 

[drgondog]

My numbers for victory claims are correct. The 973 figure comes from Molesworth among others. The P-40 was the Allied type with the highest number of claims in the CBI by far. I don't think that is exactly news. But the CBI was a tertiary Theater and there weren't a lot of the more high performing Allied types in action there especially early on (in the mid-war).

I'm not familiar with 'Molesworth', or 'among others'. What are the root citations for your sources? USAF 85 is the root for all WWI and II and Korea US Victory Credits - upon which Dr Olynyk expanded via documented sources and were accepted by USAF Historical Research Center. Olynyk was an excellent researcher and got his PhD thesis on this subject many years ago.

RIP Frank.

For US and Commonwealth VCs you should rely on Olynyk and Shores.

The AVG probably had fewer planes operational (less than 100 total) in the CBI than the number of early Mustangs (later) operating there, and the AVG was not operational for that long, nor did the 23rd FG have a massive air contingent either. Nor was there a dearth of targets. The same outfits flew missions with different aircraft and got different results.

It was operational for seven months at Group level strength - that fluctuated. In a target rich environment against late 1930s vintage aircraft mix of fighters and bombers.

Although the Mustang was clearly an excellent design, very fast, long ranged, and quite agile in it's later incarnations, the record of the Allison engined Mustang, as a fighter, wasn't so great. This is worth figuring out, I am not sure precisely why but I suspect it does have something to do with the metal control surfaces, the strengthening of the tail, and / or the rigging of the ailerons. It may have also been other things such a training, maintenance, or specific Theater conditions. Maybe the different configurations of the guns too. Gunsights?

No. The Mustang I and Allison based variants all had fabric control surfaces, as did all the P-51B and D until the D-20/-25 when the metal elevator kits and incidence change kits were delivered to retrofit in early 1945.

The sole 'manuever' deficiency vs P-51B/D was the aileron rigging from +/1 10 degrees to +/- 10, 12, 15 degrees, That said, 'it' (XP-51, P-51, A-36 and P-51A out rolled the P-38, 39, 40 and P-47 at speeds above 300KT TAS. The P-40 our rolled the P-51A in slow, middle airspeed range. The P-51A outclimbed the P-40 and 47 - and climbed with the P-38F/G until 15K+. The P-51-NA (4x20mm) comparison for AAF operational suitability tests vs P-39Q, P-40N, P-38G and P-47D was deemed the 'best fighter below 15000 feet - and it was at least 10mph slower than P-51A across the entire envelope.

Pacific Fighters John Muszala II is one of the Rare warbird pilots who has flown all the primary Allison/Merlin Mustang variants including the P-51A/B/C/D and he will tell you that the P-51A is more agile than B/D- which it Should be in every domain except roll - because of excess HP to drag and lower W/L

But it's pretty clear the P-51A / A-36 and various British Allison Engined Mustang variants did not perform as well as fighters as they could have. As the later merlin-engined variants did. This is why they were used more for recon and as dive-bombers. And I don't think that is entirely down to the merlin engine either.

You can argue 'did not SCORE as well' but not 'did not Perform as well as fighters as they could have' - had they been in-theatre in quantity with their P-39D/N, P-38F/G, P-47C/early D counterparts for 1942 and 1943. Scoring was a function of quantity deployed in combat at the same time period.

I don't know if you are familiar with Mike Williams' spitfireperformance.com website. If not, you should take a deep dive into test pilot reports for the various marks as well as comparisons. If so, you should spend more time studying them.

 

[GregP]

Nice post, Bill.

Have you published your work on the MTO yet with victory tally? If so, where can I get a copy?

 

[drgondog]

Hi Zipper.

There was a war on and taking a working Spitfire (or anything else) from the front line to fit a new fin and rudder or to recontour an elevator or stabilizer, etc. likely wasn't high on the priority list. Sure, they COULD have been modified, but they were flying and fighting at the time and changes were generally cut in at some point and not always retrofitted. Things like the dorsal fins fitted to P-51D and some B/C models as well as dorsal fins for P-47s WERE sometimes field-fitted, as were things like P-38 dive flaps.

Here's a good study of four P-51Ds. Only one, the 2nd one, has the dorsal fin extension:
View attachment 662093

So, the dorsal fun mod was either field-installed or the change was cut in somewhere between 44-1310 and 44-13926 (the two serial number of the nearest two). I'd have to look that up to be sure which. Somewhat obviously, these are early D models.

Here's a 2-seat TR IX in formation with an XIV. Note the different vertical tails since the Griffon had quite a bit more horsepower. The XIV has more chord, for sure, and a bigger fin:
View attachment 662094

Greg - the Factory DF was installed on 44-13903. 953 is a factory dorsal fin inst'l. 953 arrived at 361st around very late July/early August. Dad was shot down by flak (and rescued by Priest) in 950 on August 18th. The kits began rolling in in early September, so I'm guessing that pic was in August/September 1944.

 

[tommayer]

I'd say the super basic definition of a fighter is an aircraft which destroys enemy aircraft. Which is the criteria I have been applying here.

Does that mean B-17s-24s etc were fighters? They destroyed enemy e/a.

 

[drgondog]

Nice post, Bill.

Have you published your work on the MTO yet with victory tally? If so, where can I get a copy?

Greg - I'm currently working on P-51D/Lightweights. I have the Olynyk database.

As you probably know he passed away about two weeks ago. He was working on an Opus with Christopher Shores to integrate Commonwealth/US Victory credits.

 

[Wild_Bill_Kelso]

I'm not familiar with 'Molesworth', or 'among others'. What are the root citations for your sources? USAF 85 is the root for all WWI and II and Korea US Victory Credits - upon which Dr Olynyk expanded via documented sources and were accepted by USAF Historical Research Center. Olynyk was an excellent researcher and got his PhD thesis on this subject many years ago.

Carl Molesworth who wrote about a dozen or so books on the P-40, including most of the Osprey books, and some on other aircraft including P-51. But this same number was also found in several other sources.

Publications — Carl Molesworth

www.carlmolesworth.com

I'd like to understand better what you are getting at here. It's quite possible that 973 is off slightly, I believe it is correct however sometimes incorrect statistics get repeated by many fairly reputable sources. But I really doubt it's off a lot, and seeing as the next highest victory claim total is about 1/3 of that, overturning the overall conclusion that P-40s got by far the most VC in the CBI does not seem to be likely to me. Do you have a substantially different figure?

For US and Commonwealth VCs you should rely on Olynyk and Shores.

I do have several of Shores books, though he isn't immune to mistakes (his books don't all agree with each other for one thing). But he's a good researcher and I've learned a lot from his work.

It was operational for seven months at Group level strength - that fluctuated. In a target rich environment against late 1930s vintage aircraft mix of fighters and bombers.

Yes and the 23rd FG, though operational far longer, didn't have that many aircraft either. We know AVG did face Ki 43s and the 23rd FG certainly did. Basically the same aircraft that P-51A (etc.) had a lot of trouble with. I think you can compare like with like in the CBI in terms of number of aircraft available in a given period, sorties flown against basically the same opponents, and what the outcomes were.

No. The Mustang I and Allison based variants all had fabric control surfaces, as did all the P-51B and D until the D-20/-25 when the metal elevator kits and incidence change kits were delivered to retrofit in early 1945.

The sole 'manuever' deficiency vs P-51B/D was the aileron rigging from +/1 10 degrees to +/- 10, 12, 15 degrees, That said, 'it' (XP-51, P-51, A-36 and P-51A out rolled the P-38, 39, 40 and P-47 at speeds above 300KT TAS. The P-40 our rolled the P-51A in slow, middle airspeed range. The P-51A outclimbed the P-40 and 47 - and climbed with the P-38F/G until 15K+. The P-51-NA (4x20mm) comparison for AAF operational suitability tests vs P-39Q, P-40N, P-38G and P-47D was deemed the 'best fighter below 15000 feet - and it was at least 10mph slower than P-51A across the entire envelope.

I'll take your word for that, as I acknowledged earlier, I don't know what the details of the precise issue was. But i believe there was an issue - and I have spoken to several pilots from the CBI including two who flew both P-40 and P-51 in the CBI and they told me as much. Admittedly one of them only had a single flight in a P-51 and was badly injured during that flight so he was probably biased.

Pacific Fighters John Musula II is one of the Rare warbird pilots who has flown all the primary Allison/Merlin Mustang variants including the P-51A/B/C/D and he will tell you that the P-51A is more agile than B/D- which it Should be in every domain except roll - because of excess HP to drag and lower W/L

You can argue 'did not SCORE as well' but not 'did not Perform as well as fighters as they could have' - had they been in-theatre in quantity with their P-39D/N, P-38F/G, P-47C/early D counterparts for 1942 and 1943. Scoring was a function of quantity deployed in combat at the same time period.

I don't know if you are familiar with Mike Williams' spitfireperformance.com website. If not, you should take a deep dive into test pilot reports for the various marks as well as comparisons. If so, you should spend more time studying them.

I see different units with different aircraft types flying on the same missions (for example with 23rd FG) and getting markedly different results. I don't know why this is such an unpopular observation but it's not arising from my imagination, or any malice or prejudice on my part. Frankly i was surprised.

Not that anyone cares, but I actually like the Allison Mustang, it just seems like there was some kind of issue with it. It could have been just a training issue but there is some evidence against that. It could have also been a maintenance, leadership or tactics issue. But there seems to have been an issue.

And I know which one the test pilots liked the best, but I'm talking about operational history here. Not tests.

 

[Wild_Bill_Kelso]

You can find many different reports. Usually, when someone was attacked, the attackers had the upper hand by virtue of diving from above or from the sun, or whatever. Find the reports when the P-51A did the attacking and you will find the encounters where the P-5A had the advantage. It DID reach its potential, but the 2-stage Merlin-powered version was produced in WAY higher numbers, flew higher and faster, and got the bulk of the missions where victories over attacking enemy fighters were likely to happen.

Kelso, you are completely free to feel the P-51 wasn't a good fighter and nobody will obviously be able to change your mind. Perhaps we should not try since everyone has an opinion backed by whatever facts they have dug out over the years. You won't likely change anyone else's opinion, either. It's all good. The war is long over, and discussion of the merits of the various aircraft makes these things interesting.

I've sat through maybe a couple of hundred talks with WWII fighter pilots. Almost every single one of them felt the aircraft they were assigned to fly was the best fighter in the world, regardless of which one they flew. Most only flew ONE fighter, so you can draw your own conclusion from that.

Cheers.

I appreciate the sentiment, and agree for the most part, but I never said this:

"you are completely free to feel the P-51 wasn't a good fighter"

Why do people keep putting words in my mouth here? Haven't I literally said the opposite of that several times?

 

[GregP]

Hi Bill.

Since last emailing you, I have a new email: will PM.

Would love to acquire your work when completed or help review anything you like. As you know, I'd also love to help with databases, should that happen to be of any assistance. If not, I'll take ... err ... buy a copy when it is finished.

Manually inputting Frank's database is something that will have to wait until I am no longer restoring aircraft. Currently working on various components in a G-73 Grumman Mallard and am starting to help restore a pair of teardrop Erco turrets from a PB4Y Privateer with partner Phil Laidure. Same Erco as made the Ercoupe. The aim is to make them able to function except, of course, non-firing guns, and to perhaps get them back in the PB4Y at Yanks Air Museum. They're just about finished with a Bell P-63A and it is nearing first flight. Frank Wright's team (Randy Purdey and Casey Wright, mainly) have done an amazing job. It looks quite factory-fresh. These guys are good.

 

[GregP]

I appreciate the sentiment, and agree for the most part, but I never said this:

"you are completely free to feel the P-51 wasn't a good fighter"

Why do people keep putting words in my mouth here? Haven't I literally said the opposite of that several times?

Funny, I have that definite impression. You didn't say it quite in those words, but you strongly convey it. Recall your chosen screen name said, in Animal House, "Did we give in when the Germans bomber Pearl Harbor? I don't THINK so!" or words to that effect. So, maybe John Belushi has something to do with it?

That being said, we all maybe tend to read a bit between the lines. Everyone except ME, that is ...

 

[Milosh]

GregP, are you looking for trouble by posting your e-mail addy?

 

[Wild_Bill_Kelso]

Ok fair enough. My point was that the Allison-engined Mustang seems to have had some issues which restricted it's effective role somewhat, and I suspect these were design issues that weren't fully tweaked, though I acknowledge that may have been really to do with some other factors than the physical characteristics of the aircraft (like training, tactics or maintenance). I think the Mustang in general was (obviously) one of the best aircraft of the war.

This was all part of a point that getting to the 'sweet spot' with a fighter design was quite difficult. I think it took a while to get there with the Mustang, though unlike many other promising designs, the Mustang was in production early enough to have a significant effect on the war.

This is basically the same point I was making, or trying to make about the F8F, vis a vis a longer ranged Spitfire. The devil is in the details and it was certainly hard to make a fast, agile (and combat ready) fighter with long range. Especially one which could excel at higher altitudes. Maybe impossible in the 1930s to 1940 or 41. I think that was becoming more possible as the engines got more powerful, though still clearly very difficult.

 

[Wild_Bill_Kelso]

GregP, are you looking for trouble by posting your e-mail addy?

Yeah i was going to mention that too. Better to send that via PM and edit your post above to remove it.

 

[GregP]

GregP, are you looking for trouble by posting your e-mail addy?

No, but I suppose you have a point. Thanks, Milosh and Kelso. Duhhh ...

 

[GregP]

It certainly is a different world when an email can make trouble for you. But, the reason I have a new email is the old one got hacked.

Open keyboard, insert foot.

 

[Wild_Bill_Kelso]

The interwebs are an amazing resource, but also amazingly treacherous...

 

[GregP]

Sounds exactly like Washington D.C.

 

[pbehn]

That's an interesting observation, but it's an apples to orange one: A Spitfire VII/VIII/IX as described here*(see footnote 1) with the aft tanks filled is tantamount to a P-51B with it's center/aft tank filled as well

Aircraft	P-51B/C​	P-51B/C​	Spitfire VII/VIII/IX​
​ Configuration​	​ All Tanks Filled​	Wing & Center Tanks Filled​	All Tanks Filled​
​ Fuel Load (US Gallons)​	​ 184 Gallons​	269 Gallons​	225.8 Gallons​

​

With externals on a full load, you end up with either 419 gal. for the P-51B and 285.8 or 333.9 gal*(see footnote 2) for the Spitfire VII/VIII/IX.

As for 90 imp. gal slipper tank, it seems like it probably was if they operated routinely above 14000'.

Footnote
1. I was looking through some FM's on avialogs, and there wasn't any mention of the Mk.IX having 13 gallon tanks in the wings interestingly. That might have been something that evolved into being, but the aft tanks were definitely present as described.
2. There was a proposed 50 imp. gal. tank to be carried in lieu of the 90 imp. gal. slipper tank.


I'm not sure if I missed this earlier, but why weren't these backfitted to the VII/VIII models?


Okay, that leaves me with three questions

1. Did the leading edge tanks used on the VII/VIII have 13 or 13.5 gallon capacity?
2. Did the VII/VIII have the aft tanks in any sub-variant?
3. Did the IX have the leading-edge tanks?

I remember it mentioned that fighters were used to cover the bombers during the lead-up to D-Day, as well as mentions made by Leslie "Willie" Hay (RAF, Bomber Command) in his book about fighter sweeps occurring ahead of his position.

From what it seemed, during Korea, fighter sweeps were usually set-up so that they would R/V with the bombers as they'd approach enemy territory, surge ahead and clear-out the way and head-on back. The USAAF largely used s-weaving over the formations, but there were fans, race-track patterns, and some did appear to just surge ahead to plow out the way.

Unfortunately for the Spitfire, the Mustangs aerodynamic advantages were not just in speed. On the same engine the Mustang was approx. 30MPH faster than the Spitfire but the same was true on cruise settings, not just maximum power, so the Mustang went 30miles further per hour as a ball park figure, with the same fuel load, six hours cruising took the Mustang 180 miles further or 90 miles range.