Thunderbolts and Mustangs versus the Jagdwaffe (split topic)

[Franek Grabowski]

Juha
Yes, please, but I do not see any reason why an operational range should be very different.

Ruy
Just a short comment concerning Japanese aircraft - most popular types were Zero and Hayabusa, then perhaps Shoki. They were used through the whole war of 'Pacific'. I consider other types both not significant and not really mature. Problems were not limited to poor quality fuel, though it was doubtless one of the factors.
Going back to Mustang vs T-bolt, one of the principles of aerial tactics is to keep own bases out of reach of enemy forces. Introduction of T-bolt pressed Germans to the Netherlands, then look what was a real impact of Mustang. And the latter was not only better in range.

Artie

1. Allison P-51s: “But by 1944 there were no jigs available and no production run was possible”. I cannot comment on the tooling being destroyed, but the engineering of V-1710 engines in Mustangs continued through the war.

It appeared only in form of XP-51J lightweight Mustang.

IIRC, the final development of the Mustang lineage, the P-82, did have V-1710 engines. Certainly, It was within the capability of WWII US aircraft industry to tool up quite rapidly for production changes. It should also be noted that the P-82 was also a heavier a/c than either the P-51 or P-47 in any version (BTW, a squadron was based near my home in the late 1940s and IMHO they were the most exciting piston fighter ever to see and hear make a low pass).

I am not sure if we can discuss P/F-82 here, it was a quite different aircraft.

2. P-47N: “ This aircraft was specifically designed for the SWP and having increased weight had little chance with lighter German types.” IIRC, by the beginning of 1945, the Eighth Air Force had made the decision to standardize on the P-47N as it’s long range escort fighter and some had been delivered to England in early 1945, but did not make it to squadron service prior to V-E day.

The source please. By the way, if true, was not it due to planned use of 8 AF against Japan?

3. Weight: “Such aircraft like P-47 or B-17 were simply overdimensioned, thus overweighted, thus stronger than comparable designs - performance suffered.” I really believe your opinion on that issue also needs to be questioned. EVERYTHING ELSE BEING EQUAL, it is true that lighter is better! But in the real world of aircraft design almost nothing is equal between two designs (unless they share some major components, like the engines, then they diverge).

Climb speed is approximated to be a proportion of difference of power available and power required to a mass multiplied by gravity. Try to proove me then, that weight is not an important factor in aircraft's performance!
Of course this increasing weight may be compensated by increase of power but this also means increase of engine's weight and fuel consumption. The latter results in loss of range - increase of tanks volume leads again to increase of weight, not only of extra fuel but also of extra tanks and construction around them. This becomes further complicated if dimensions are affected as this results with aerodynamical changes - evolution of P-35 is a very good sample.

This meant tradeoffs in some areas, but from everything I have been able to learn, the P-47 was really a pretty good handling machine and aerodynamically clean for a WWII piston fighter.

T-bolt had significantly lower critical Mach number comparing to Mustang or Spitfire. Not a very good proof of aerodynamic cleanless.

If just being smaller and lighter were the only criteria, then the Caudron 714 should have been the best fighter of WWII, hands down.

Polish pilots who flew Cyclone considered it a very pleasant aircraft, hands down. Cyclone's problems were not in weight itself but in aerodynamics, strenght and armament. Quality and performance is extrapolation of several factors, that is correct. T-bolt with a Cyclone's weight would be doubtless a designer's dream.

IMHO, neither the B-17 or P-47 were overweight, but had very sturdy, easy to maintain airframes that could accept severe combat damage and make it home with crew survival (In a war of attrition, not a performance parameter to be ignored).

While aircraft is designed, maximum loads are calculated and then multiplied by a safety factor. Then the airframe is designed to sustain those gross loads. Most commonly 1,5 factor is used in aviation (for a comparison in cars it is 8 IIRC), but sometimes other, usually higher factors were used, especially in older designs when theory of strength was not so well known. Of course use of higher safety factor results in stronger construction but also greater weigth. Longevity of such designs like DC-3 is a direct result of this approach.
By the way, comparison of bombload of B-17 to other, I would say more matured, 4 engined aircraft like Lancaster or Liberator is not very favourable towards the former. I think there was a wartime song about it.

4. Other participants in this discussion: “Sorry, performance figures are clear, it is just only most authors have no slightest idea what thery are telling about.” My question is; does this statement refer to others who have contributed to this thread? If that was your intent, then I would like to ask, what is your background?

My intent is clear. I just only state that very few of authors of published aircraft monographs have any engineering background, thus more than often their conclusions are wrong and misleading. This leads to such a nonsenses like attributting clipped wings to LF Spitfire variants for example.

Six Nifty .50s

Which performance figures?

All!

Unless the authors personally engaged P-47s in combat, their opinions are unnecessary. Based on their practical experience, several German fighter pilots suggested the Thunderbolt was a more dangerous and troublesome opponent than the Mustang.

I do not see any reason to believe the personal engagement's experience is a decisive factor when discussing those matters. And while we are at German pilots' opinions, by 1944 they believed every aircraft was a US one and not able to distinguish RAF types.

Some enemy pilots assumed that was true of the older Thunderbolt, because of its immense size, but they paid for that mistake with their lives.

Well, it seems not so apparent, when getting through 8 AF narratives.

I will not forget that many people once used the same excuse about German records. Certain Japanese loss reports have survived, and probably these are no less honest than their opponents. Like every other air force, RAAF Spitfire units inflated shootdowns substantially. One figure quoted amounted to about 7:1 overclaiming. I'll look into it more on next trip to the library.

Based on my research concerning Polish losses in WWII, I consider German records highly unreliable, especially as practically only source are GQ6 returns.

One cannot escape common knowledge that liquid-cooling systems were easily knocked out with one bullet or shell splinter.

Never claimed anything different, nonetheless I talked to several Polish 2 TAF Spitfire pilots and I never heard them complaining a lot about the problem. Well, if you have any particular questions, put them here - a good excuse to call one of them by phone.

Another factor is that Spitfires and Merlin Mustangs had persistent structural problems, especially when put into high speed dives. Both planes showed an alarming tendency to shed their wings or tail on pullout. It was an adventure to plug all of the coolant leaks on the P-51B. In 1942, 36 Spitfires were under investigation for structural failures and in 24 cases the tail unit broke off in flight. By 1944, the Spitfire was often used as a fighter-bomber and another hazard was found in that the engine mounting U-frames would buckle in dive pullouts.

IIRC through the whole WWII one Polish pilot was killed due to Spitfire's structural failure, while another was forced to bail out. Both did it 'on their wish'. Indeed several aircraft returned damaged but this was not that very common and more a myth than a problem. Otherwise, Spitfire's design was sturdy enough to allow pilot to return home on a write off - in case of other aircraft pilots had no position to complain, being already 6 feet under.

The A-36 at least had dive brakes to control descent, so these were safer to fly while vertical bombing. But otherwise, I cannot imagine why anyone would want to pilot a Mustang or Spitfire with a ground attack unit.

Due to excellent aerodynamics, Mustang accelerated pretty quickly thus making some trouble in dive bombing but I never claimed it was an excellent ground attack aircraft! More, T-bolt was better, hands down, just only useless as a fighter.
By the way, while we are discussing ground attacks, why not to discuss effectiveness of aerial support in general? It does not look impressive at all.

Well the main interest of Jagdwaffe (B-17s and B-24s) did not dive down to drop bombs from low altitude, so the German response is a relevant point.

Yes, but USAAF considered it is easier to not to allow Germans to climb rather than to escort bombers. Mustang did it possible.

The best part of the Merlin was the 2-stage supercharger attached to it; not the engine itself which was fragile. Main bearings were weak, and the carburettor was worthless until replaced with the American type.

I have never heard pilots complaining on reliabilty of their Merlins but there were several cocnerning Allisons - ORB of 309 Sqn notes frequent visits of Allison engineers trying to rectify experienced problems.
What do you mean by American carburettor?

On average the Allison lasted three times longer before rebuild, even though manifold pressure was often overboosted to about 20 lbs. -- not recommended by the manufacturer, but the engine held together reliably.

What fuel was used?

Note that air racing teams flying P-51Ds installed Allison connecting rods to prevent their Merlins from blowing up. Without this modification, the Mustangs could not compete with the speedy Bearcats at Reno.

Aircraft races are so specific matter, I do not think any experience applies here. Otherwise, I do not have any objection against admitting that some parts were better here rather than there. The fact is that Merlin was most common Allied V-12 engine, however.

Not many air combats took place over towns inside Normandy. The Luftwaffe did not often penetrate the fighter cover surrounding that part of France -- at least not when the sun was shining.

Several managed to the beaches through June 1944 but indeed several more found their fate on the way to. But it does not change the fact all the combats were low level ones.

Besides, the Luftwaffe was short of petrol by the autumn of 1943, so the Focke Wulfs and Messerschmitts usually did not bother with Allied fighter-bombers, medium bombers and their escorts, or other fighter patrols that were not tied to B-17s and B-24s. What little avgas remained on tap was needed for training.

When I used a lack of fuel argument in an another discussion, Don Caldwell gently expressed remarks that fuel deficenties started during or after Normandy Campaign.

It is widely believed by fighter pilots that in tens of thousands of engagements, the overwhelming majority of pilots shot down were hit by gunfire from another pilot who was not seen by the victim. Thus, I would challenge you to identify the number of combats in which a difference in 'maneuverability' made a difference in the outcome.

Indeed most pilots were downed in the first attack but judging by combat reports and other relevant documents of PAF, I would say several downed pilots were awared of danger but simply unable to undertake successfull evasive action.

Regards

[Jens]

Of course the figures i have posted are claims and not confirmd kills. On the other side they show the relative comparsions between the types. So it's notable for the statement to say, mustangs got much more.

Don Caldwell's site is a little bit... one third of all Luftwaffe planes were destroyed at Eastern Front, all over the war.

[Ruy Horta]

Originally Posted by Franek

Just a short comment concerning Japanese aircraft - most popular types were Zero and Hayabusa, then perhaps Shoki. They were used through the whole war of 'Pacific'. I consider other types both not significant and not really mature. Problems were not limited to poor quality fuel, though it was doubtless one of the factors.
Going back to Mustang vs T-bolt, one of the principles of aerial tactics is to keep own bases out of reach of enemy forces. Introduction of T-bolt pressed Germans to the Netherlands, then look what was a real impact of Mustang. And the latter was not only better in range.

The Japanese discussion although interesting, should be continued elsewhere, needless to say I do not share your overall lacking assessment of operational Japanese fighter types. You seem to draw most of your conclusions on the CBI front and extrapolate them beyond said narrow base.

WRT to the Tbolt vs Mustang debate, we seem to continue flying around the same light bulb, like moths in the night.

1. The Mustang was a very capable fighter, as stated before.
2. The Thunderbolt could have done the same job, being in some areas superior (high altitude escort) or at least equal, and in others playing catch up (like range).
3. In service of the US VIII. AF, the Thunderbolt engaged the Jagdwaffe when it was relativly speaking an equal adversary, hence its achievements must be waged accordingly.
4. The Battle over the Reich (daylight) was basically lost by Big Week, or at best the spring of 1944, when the Mustang was only starting to replace the Thunderbolt as the main escort type.

These are generalizations, but they need be, if this discussion isn't lost in (minor) detail and related subjects, like Japanese fighters and their engines.

Originally Posted by Jens

Of course the figures i have posted are claims and not confirmd kills. On the other side they show the relative comparsions between the types. So it's notable for the statement to say, mustangs got much more.

Don Caldwell's site is a little bit... one third of all Luftwaffe planes were destroyed at Eastern Front, all over the war.

You should offset the number of US claims against a number of variables.

Number of operational a/c, number of encounters, type of a/c claimed, quality of opposition etc etc etc. Whereas 1943 Thunderbolt claims will be versus mainly well trained and well equipped Jagdwaffe units, 1944/45 Mustang claims will cover the whole range of Luftwaffe spectrum, including trainers, and generally far less trained pilots. So although the Mustang claim might be (dramatically) higher, the value might actually be substancially lower.

Don Caldwell in his assessment also focuses on numbers alone, and forgets the qualitative drain of the earlier Eastern Front attrition (1941 to mid 1943).

That's why these stats only proof to be half of the picture if taken at face value.

[Graham Boak]

I don't believe that your points 2 and 4 are valid.

Point 2: The Thunderbolt was well behind the P-51 in range, and never caught up - or got anywhere near. As this was the key point in the replacement of the P-47 by the P-51 in the 8th AF, I do feel that to argue otherwise misunderstands the very point under discussion.

Point 4: the daylight battle was not lost before Big Week, or even after. Big Week was a propaganda claim, not a major Luftwaffe defeat in numbers. The daylight battle was lost only when US fighters rendered the whole of German airspace vulnerable (which means the P-51) , and after the heavy losses by the Jagdwaffe over Normandy.

There is a very good point to be made that the Jagdwaffe was previously weakened by the continuous attrition from the P-47 (and P-38!) units. However, to claim more is, in my opinion, not supported by the evidence.

[Franek Grabowski]

Ruy
I agree Japanese aircraft should not be discussed here.
Concerning your other points.
T-bolt superiority in high altitude performance was questioned by some pilots - taken from Il-2 forum.
James Tapp: 8 victories 15FG (PTO)
"Through the end of the war I flew 33 hours in the P-39, 788 in the P-40, 267 in the P-47D, 218 in the P-51D(all 8 kills were recorded in this type) and even 1 hour in a P-38L.
When we transitioned to P-51D's, I was making claims about its superiority over the P-47s we were still flying. An argument rose: "Yeah, but the P-47 outperforms the P-51 above 30,000 feet." The Republic tech was particularly sensitive about this. Our engineering officer, based on what I was claiming, bet the tech that the P-51 could outrun the P-47 above 30,000. The Group CO, Lt.Col. Jim Beckwith, had a P-47D28 with a bubble canopy specially readied to race the Mustang. The Thunderbolt's wing racks were removed and it looked like it had been waxed. The P-47 was flown by vice CO Maj. Emmett Kearney, while I went out to the line and jumped into one of the Mustangs there and taxied out behind Kearney.
I flew on his wing and had to hold the P-51 back while we climbed to 30,000 feet. After we reached altitude and leveled off, he signalled that he was going full power. I stayed with him for awhile and asked, "Is that all you have?", to which he nodded. I then pushed the throttle full forward to 3,000 RPM and ran off and left him. TO rub it in, I dove for base, knowing that because of the P-47's compressability problem, she could not follow. I landed, grabbed a coke and a folding chair, and waited for him to taix in."
Of course you may find opposite statements but it is evident, superiority was not clear.
Concerning demise of Luftwaffe - significant quality drop occured during Spring 1944, still there were several experienced pilots and units like JG2, which performed very well in Normandy. The latter however turned to be a real hecatombe! Look that whole units were dissapearing even several times - losses of eg. JG3 were tremendous, I think that during June alone they lost double or triple number of aircraft entered combat with. In one of most famous battles of PAF, the one over Beauvais on 18 August, 12 Mustangs reduced II/JG26 strenght by 1/4! Allies simply cut down any chance to ressurect Luftwaffe and by annihilating German early warning capabilities, secured victory in the air.
Another point, to follow your argument about superior Thunderbolt role in the Big Week. Following your logic, Spitfire was then the numerically superior aircraft and was taking part in hundreds of sorties covering Northern France, Belgium and the Netherlands. Also, paraphrasing your words, Spitfire engaged the Jagdwaffe when it was relativly speaking an equal adversary comparing to Thunderbolt times, hence its achievements must be waged accordingly. Thus I understand you will claim Spitfire won the airwar over Europe.
Actually, US air offensive so successfull because of Mustang and Spitfire part - Spitfires did short range escort, Thunderbolts - mid one and Mustangs - the longest. As the German tactics was to attack at the limit of range of escort and due to change of US tactics after Schweinfurt disaster, intorduction of even relatively few Mustangs did a major change in warfare. In turn, Thunderbolts alone could do nothing.
Then concerning your reply to Jens, if you claim losses in the East were so significant, you must admit that:
- Luftwaffe in the late 1943 was not an equal opponent to P-47,
- qualitative drain of the earlier Battles of Poland, France and Britain attritions (1939 to mid 1941) was a decisive factor.
A little bit chaotic, sorry.

[Ruy Horta]

I'm trying to restrict the discussion to Thunderbolts and Mustangs, and the Strategic daytime campaign, and have clearly stated so for clearity (you might back track to some of the original comments).

Up to this point there has only been opinion, little else from both sides of the argument. Ironically I've only stated that the Mustang's reputation is somewhat inflated, nowhere did I add that the Mustang wasn't an excellent fighter. However you've repeatedly stated that the Thunderbolt wasn't much of a fighter, but your counter case isn't based on strong evidence. I'm restricting myself to saying that the Thunderbolt could have done the same job and to some extend actually did the job.

Let me clearify that I am not a Thunderbolt fan nor Mustang detractor, the Luftwaffe side interests me more, this argument can be repeated until judgement day without us agreeing (without meaningful figures).

I fault myself for being to lazy to prepare a proper case for my opinions.

[Franek Grabowski]

Ruy
As you wish, specifications of types concerned taken from Joe Baugher's site. I have reworked them to allow direct comparison of parameters. I have ommitted P-47M as it appeared in service only in 1945.
Please show me, where is Thunderbolt superiority.

Speed
P-51B-1-NA
388 mph at 5000 feet, 406 mph at 10,000 feet, 427 mph at 20,000 feet, 430 mph at 25,000 feet, 440 mph at 30,000 feet.
P-51C-10-NT
395 mph at 5000 feet, 417 mph at 10,000 feet, 426 mph at 20,000 feet, 439 mph at 25,000 feet, 435 mph at 30,000 feet.
P-51D-25-NA
395 mph at 5000 feet, 416 mph at 10,000 feet, 424 mph at 20,000 feet, 437 mph at 25,000 feet.
P-47D-25-RE
350 mph at sea level, 375 mph at 10,000 feet, 406 mph at 20,000 feet, 429 mph at 30,000 feet.

Range (note speeds!)
P-51B-1-NA
on internal fuel 550 miles at 343 mph at 25,000 feet, 810 miles at 253 mph at 10,000 feet. With maximum external fuel, maximum range was 2200 miles at 244 mph.
P-51C-10-NT
internal fuel 955 miles at 397 mph at 25,000 feet, 1300 miles at 260 mph at 10,000 feet. With maximum external fuel, maximum range was 2440 miles at 249 mph.
P-51D-25-NA
950 miles at 395 mph at 25,000 feet (clean), 2300 miles with maximum fuel (including drop tanks) of 489 US gallons under most economical cruise conditions.
P-47D-25-RE
950 miles at 10,000 feet. Range with maximum external fuel was 1800 miles at 10,000 feet at 195 mph.

Climb and ceiling
P-51B-1-NA
An altitude of 5000 feet could be attained in 1.8 minutes, 10,000 feet in 3.6 minutes, 20,000 feet in 7 minutes. Service ceiling was 42,000 feet.
P-51C-10-NT
An altitude of 5000 feet could be attained in 1.6 minutes, 10,000 feet in 3.1 minutes, 20,000 feet in 6.9 minutes. Service ceiling was 41,900 feet.
P-51D-25-NA
Initial climb rate was 3475 feet per minute.An altitude of 5000 feet could be reached in 1,7 minutes, 10,000 feet in 3.3 minutes, 20,000 feet in 7.3 minutes. Service ceiling was 41,900 feet.
P-47D-25-RE
Initial climb rate was 2780 feet per minute. Climb rate at 30,000 feet was 1575 feet per minute. Service ceiling was 40,000 feet

Weight
P-51B-1-NA
6840 lbs empty, 9200 lbs normal loaded, 11,200 lbs maximum loaded.
P-51C-10-NT
6985 lbs empty, 9800 lbs normal loaded, 11,800 lbs maximum loaded.
P-51D-25-NA
7125 pounds empty, 10,100 pounds normal loaded, 12,100 pounds maximum.
P-47D-25-RE
10,700 lbs empty, 14,600 lbs normal loaded, and 17,500 lbs maximum.

P-51B-1-NA
One 1620 hp Packard Merlin V-1650-3 twelve cylinder Vee liquid-cooled engine. Wing area was 233 square feet.
P-51C-10-NT:
One 1695 hp Packard Merlin V-1650-7 twelve cylinder Vee liquid-cooled engine. Wing area was 233 square feet.
P-51D-25-NA
One 1695 hp Packard Merlin V-1650-7 twelve-cylinder Vee liquid-cooled engine. Wing area was 233 square feet.
P-47D-25-RE
One Pratt and Whitney R-2800-59 Double Wasp eighteen-cylinder air-cooled radial, war emergency power of 2535 hp. Wing area 300 square feet.

And additionally another comment from Il-2 site.
William Whisner: 21 victories (14.5 P-51) 352FG (15.5 WWII and 5.5 Korea)
"We exchanged our Thunderbolts for Mustang B's in Aprill 1944. The P-51 was the better of the two fighters. It was faster, had a smaller turning radius, had better acceleration and rate of climb, far outclassed the P-47 below 25,000', and a longer combat range."
"Even in a dive, for which the Thunderbolt was renown, the Mustang could hold its own. In the initial pushover into the dive the Mustang was faster, and thereafter it could keep up with the heavier Thunderbolt, which fell like a rock. The P-47 did have a better rate of roll, and with its high altitude supercharger was slightly better at altitudes above 25,000'. Although it was more heavily armed with eight .50 cal. machine guns to the Mustang B's four, in aerial combat this was no problem, as most kills were from 10 degrees or less deflection and within 250 yards - can't miss territory."
"Our guns were a continual source of frustration. Anytime we pulled more than 1.5 to 2 Gs they would jam. [We] had to take our chances with the guns whle manuevering in combat, or confine our firing to straight and level flight!"
"The flight characteristics of the Mustang were great. It gave ample warning of a stall, and generally had no sever handling faults.
(After converting to P-51D's)
"The K-14 gunsight, introduced in the fall of 1944, enabled me to shoot down six (actually seven, but my gun camera film ran out) FW-190's on 21 November 1944."
"The D had numerous modifications that made the aircraft heavier without a matching increase in engine power. In my opinion this factor subtly decreased the D's performance compared to the B."

[Juha]

Hello Franek
the reason is that N had clearly greater fuel load (556gal. internal+440gal external = 996gal vs. 269gal+150gal = 419gal for P-51D).
The mission profile was climb to 25000ft at normal rated power, cruising at 25000ft at 210mph IAS , external tanks were dropped before entering combat, in combat 5min at WEP and 15min at military power, return flight at 25000ft at 210mph IAS, allowance for 30min reserve at minimum cruise power plus some other assumptions but these are the most important ones. The combat radius of action for P-47N is given as 1000mls and that for P-51D 700mls. From another graph one can read that if the cruise was at 10000ft and other variables same as above the combat radius of action for P-51D was 750mls no info for P-47N range at 10000ft.

On P-47 vs. P-51 speeds. According to Dean's book P-47D-25 was a bit slower than P-51B but appr. as much faster than P-51D at 30000ft.

And IMHO a claim that P-47 was "just only useless as a fighter. " is rather extreme. After all one of the two most successfull FGs at ETO (there is some argument which of the two was the most successful) was 56th FG, which flew all it's time P-47 and it was a couple short times grounded because of troubles with the engines of its P-47Ms and it was also some times handicapped because of the lack of range of its P-47Ds.


Six Nifty .50s

äIn 1942, 36 Spitfires were under investigation for structural failures and in 24 cases the tail unit broke off in flight.

IIRC the structural failures were mostly confined to early Spit Vs and the problem was firstly cured by installing bobweights to elevators control cables and then more elegantly by local strengthening.

Juha

[Franek Grabowski]

Juha
Yes, perhaps my words sound too strong but I would like the people to show real, documented advantage of Thunderbolt. As yet we are discussing myths.
Have to get through the data you posted, will let you know what I think tomorrow.

Six Nifty .50s

In 1942, 36 Spitfires were under investigation for structural failures and in 24 cases the tail unit broke off in flight. By 1944, the Spitfire was often used as a fighter-bomber and another hazard was found in that the engine mounting U-frames would buckle in dive pullouts.

What is the source of your information?

[Ruy Horta]

Franek you act as if you are presenting some great case, quoting (quite selective I must add) some figures from a website that can be found on the average bookshelf. There are no myths here, there are no great thruths either, just a discussion getting slightly out of wack.

Perhaps it is time to end the debate on a disagreement, not on a so called "myth busting crusade" which to me sounds a bit too much like self applauding.

At which note I'll bow out of this debate and leave the arena to you.