P-47, 1943 in ETO: achivements?

[tomo pauk]

What was real importance of the P-47 to the Allied war effort, in 1943, in ETO? How much it was a hindrance to the LW fighter arm that was trying to tackle the heavies?
IIRC one of our British members posted translated LW reports about brawls vs. 'Pigs'?

 

[Mike Williams]

Encounter Reports of P-47 Pilots comes to mind...

 

[tomo pauk]

Thanks for the feedback, Mike.
I'd really love to read again the translated LW reports, though

 

[drgondog]

The LW learned pretty quickly that there are pigs and then there are pigs that should not be underestimated. The P-47C with the thin prop and no WI was a different pig from the P-47D's that quickly added range, paddle prop and WI and became a 'boar' that was embarrasingly tough to corner and kill at 25000 to 30000 feet.

The P-47D that Hans Warner Lerche tested after being captured intact November 7 near Caen was a D-2-RA without WI but the -11's were arriving in England and WI kits were installed on -5, -6 and -10's in November/December. He noted that Roach's ship was not particularly interesting except straight speed, decent roll, dive and firepower. Unstated was that the P-47s soon had the power and blade performance to turn and climb at that same altitude.

 

[tomo pauk]

The German reports metion Pigs in a respecful manner - they were mentioned as a hurdle, or a dam, between LW fighters and USAF bombers. Agreed that P-47 in 1944 was a whole new player in the field, however the 1943 is my interest.

He noted that Roach's ship was not particularly interesting except straight speed, decent roll, dive and firepower.

Seems like a cocky comment from the test pilot?

 

[CobberKane]

I've often wondered whether the comments of the most experienced test pilots might tell us as much about their predilictions as the aircraft they are testing. Posted on another thread somewhere are the comments of a Russian pilot who tested the P- 47 and stated catagorically "this was not a fighter." Not in the vein of a Yak-9 it wasn't, but experience in the ETO would suggest it was pretty good at shooting things down in any case.
The P-47 seems always to have been a love it it or hate it proposition. Those who got it - dive, zoom, firepower - loved it. Those who tried to fly it like a P-40 or Spitfire hated it - or got shot down in short order.

 

[alejandro_]

The P-47 seems always to have been a love it it or hate it proposition. Those who got it - dive, zoom, firepower - loved it. Those who tried to fly it like a P-40 or Spitfire hated it - or got shot down in short order.

I always thought that only a country like the US could afford to produce and deploy the P-47 in such huge numbers. I am not surprised that foreign test pilots were surprised, the Thunderbolt could reached a weight of 8 tons, comparable to a Bf 110.

Seems like a cocky comment from the test pilot?

He did change his mind when he reached a high altitude and the turbocharger started to be felt.

 

[Tante Ju]

German tactical trials of a P 47 made by the German in June 44.

"Die Thunderbolt, in Bodennähe geflogen bis auf 2000 m, macht einem ausserordenlich tragen und müden eindruck. Ihre Geschwindigkeitenwerte liegen unter denen der deutschen Jagdmaschinen. Dabei ist Wassereinspritung nicht verwendet worden. (Ein neuer vergleich wird normals erflogen). Bei dem gleinfalls geschlossenen start mit volleistung auf 3000m blieb sie weit hinter den leistungen der anderen 4 typen zurück. Auch bei einer steigung zwischen 8-9000m blieb sie hinter den Leistungen der Fw 190 zurück. In der kurve in 4-6000m höhe war sie der normalen Bf 109 überlegen, im sturz etwas schneller als die Bf 109."

English.

"The Thunderbolt, flying between near ground level up to 2000 meters, makes extraordinary sluggish and tired impression. Its speed is lower than those of the German fighters. Wassereinspritung has not been used. (naturally a new comparison is flown). At the same start with closed throttle to full power at 3000 m the performance is much lower than the performance of the other 4 types. Also in a climb between 8-9000 m it lagged behind the performance of the Fw 190. The turns at 4-6000m altitude were superior to the standard Bf 109, in dives it was slightly faster than the Bf 109."

 

[Shortround6]

I always thought that only a country like the US could afford to produce and deploy the P-47 in such huge numbers. I am not surprised that foreign test pilots were surprised, the Thunderbolt could reached a weight of 8 tons, comparable to a Bf 110.

Not quite true, the only way you are getting any P-47 except an "N" to 8 tons is with a pair of 1000lbs (or big drop tanks) underneath. But then the P-47 started with 2000hp and the Bf 110 started with 2200hp so the power to weight wasn't that far off?

You were not going to get small fighters with 2000hp engines in 1940/41 when the P-47 was planned. First flight was Mar 6 1941, 8 months before Pearl Harbor. 100/130 octane fuel didn't exist. Just plain 100 octane. The old tooth pick prop went 540lbs.
The British may not have deployed the Typhoon in such numbers but it too shows what size fighter was needed for a 2000hp engine and it could NOT fight at the altitudes the P-47 could.
The P-47 (early) could carry 1230lbs worth of guns and ammo at over 400mph at 30,000ft. Most other countries needed 2 or more fighters to carry that armament load at that speed anywhere near that height or needed a twin engine plane.

 

[tomo pauk]

<snip>

Thanks for the effort to post the report.
The following is telling:

Wassereinspritung has not been used.

Water injection (Wassereinspritzung), together with paddle blade prop enabled the P-47 to be competitive in climbs. It was already faster than German fighters above 25000 ft, the WI made it faster at lower altitudes, too. Especially when cleared to 2600 HP.

 

[Tante Ju]

I agree Wassereinspritzung was very important to make P-47 competitive, which as dragondog says it received at end of 1943.

However at same time Luftwaffe aircraft also got essential same upgrades... Wassereinspritzung and broader propellers of /AS aircraft and C3 injection for Fw 190.

 

[drgondog]

German tactical trials of a P 47 made by the German in June 44.

"Die Thunderbolt, in Bodennähe geflogen bis auf 2000 m, macht einem ausserordenlich tragen und müden eindruck. Ihre Geschwindigkeitenwerte liegen unter denen der deutschen Jagdmaschinen. Dabei ist Wassereinspritung nicht verwendet worden. (Ein neuer vergleich wird normals erflogen). Bei dem gleinfalls geschlossenen start mit volleistung auf 3000m blieb sie weit hinter den leistungen der anderen 4 typen zurück. Auch bei einer steigung zwischen 8-9000m blieb sie hinter den Leistungen der Fw 190 zurück. In der kurve in 4-6000m höhe war sie der normalen Bf 109 überlegen, im sturz etwas schneller als die Bf 109."

English.

"The Thunderbolt, flying between near ground level up to 2000 meters, makes extraordinary sluggish and tired impression. Its speed is lower than those of the German fighters. Wassereinspritung has not been used. (naturally a new comparison is flown). At the same start with closed throttle to full power at 3000 m the performance is much lower than the performance of the other 4 types. Also in a climb between 8-9000 m it lagged behind the performance of the Fw 190. The turns at 4-6000m altitude were superior to the standard Bf 109, in dives it was slightly faster than the Bf 109."

You are correct about this particular P-47. It did not have WI, and was too early to get the WI kits that were installed in December.

Lieutenant William Roach was flying P-47D-2-RA 42-22490 on November 7, 1943. The 355th had delayed return home because the 352nd FG was late getting to R/V. As a result, hampered by 90kts headwinds, three 355th pilots ran out of fuel. Two near Liege and one in the Channel. Roach's YFU "Beetle" spent the rest of the war in Rosarius Zirkus

 

[alejandro_]

You were not going to get small fighters with 2000hp engines in 1940/41 when the P-47 was planned. First flight was Mar 6 1941, 8 months before Pearl Harbor. 100/130 octane fuel didn't exist. Just plain 100 octane. The old tooth pick prop went 540lbs.

I was also referring to the fact that P-47 used a turbocharger, which were very expensive in the 1940s. The US built thousands of P-47 (and other aircraft), equipped with one.

I was reading Lerche's book. He was impressed by the performance at hight altitude (9000 meters). The Luftwaffe also captured another sample in working model (pilot landed near Rome by mistake). This one had the extra HP due to water injection.

 

[tomo pauk]

I agree Wassereinspritzung was very important to make P-47 competitive, which as dragondog says it received at end of 1943.

Yep, it also needed the paddle blade props (introduced at same time), of bigger diameter, to convert all that power into the thrust. The 'mid range' D models, despite being 1000 lbs heavier than early D models when tested, climbed some 10% faster, both when using WI (2300 HP for both Ds). Per charts at US hundred thousands, pg. 278 and 281.

However at same time Luftwaffe aircraft also got essential same upgrades... Wassereinspritzung and broader propellers of /AS aircraft and C3 injection for Fw 190.

The AS and ASM engined Gustavs were introduced half a year later than P-47s with WI and paddle blade props, so not same time. By the time ASM Gustavs were flying, the Allies have already won the air war at ETO, landed in Normandy and about to launch Operation Bagration. So the ASM was, as far as ww2 was concerned, too late in game. They still cannot beat the contemporary P-47 and P-51 above 25000 ft. By the time ASM is in the game, the P-47 was cleared for 2600 HP.

The advantages of C3 injection for the Fw-190s were canceled by A-7's and A-8's heavier weight, and the fact that BMW-801 was featuring only a single-stage supercharger. So the 1944 Antons were fine with C3 injection at ~20000 ft, however, for higher altitudes, where they are likely to encounter the 4 mots and escorts, it still does not help them.

And the thread drifts in 1944

 

[Shortround6]

You don't get performance at high altitude without paying for it at low altitude. Allison Mustangs could run with the Merlin powered ones at low altitude despite having less power. The Mig-3, a 1941 high altitude fighter, carried very light armament and didn't do well at low altitudes.

With combat in the BoB starting at 25,000-30,000ft ( almost always finishing much lower) nobody could predict what altitudes combat would be fought at in 1943. Single stage superchargers would not work at those higher anticipated altitudes ( give the desired performance).

Choices are use the turbo, build two stage mechanical superchargers, carry supplemental oxygen in tanks for the engine (nitrous oxide) or use a small engine to drive a supercharger that feeds air to the propulsion engine superchargers.

Obviously all four solutions have weight, bulk and cost issues as well as varying performance.

 

[tomo pauk]

I was also referring to the fact that P-47 used a turbocharger, which were very expensive in the 1940s. The US built thousands of P-47 (and other aircraft), equipped with one.

<snip>

Was the turbocharger really very expensive in 1940s?

 

[Tante Ju]

The AS and ASM engined Gustavs were introduced half a year later than P-47s with WI and paddle blade props, so not same time. By the time ASM Gustavs were flying, the Allies have already won the air war at ETO, landed in Normandy and about to launch Operation Bagration.

They were out earlier, by spring of 1944 (March-April I believe), so just couple of (critical) months later than the first P-47 conversions. Non-ADI AS machines appeared perhaps earlier, they were tested in the automn of 1943 already and entered production by the end of the year.

OTOH I do not believe either at all that suddenly all P-47 just had paddle props and ADI goodstuff overnight. Such things need months.. They may have started it in December, but probably took many months. Apart from that, a new prop and a bit more power did not do away with seven tons of take off weight... the P-47 suffered less at altitude at others, but it was far from nimble.

So the ASM was, as far as ww2 was concerned, too late in game.

In fact they arrived just at the same time as Mustangs and improved P-47s...

They still cannot beat the contemporary P-47 and P-51 above 25000 ft. By the time ASM is in the game, the P-47 was cleared for 2600 HP.

Of course they could, the AS machines were good at altitude. In the meantime, a considerable number of GM-1 G-6s and G-5s were produced, though I am not sure how regularly they were employed with boosters in late 1943.. The P-51 had what exact magic property over 25 000 feet? Its engine was no better, perhaps even worse (-7) at altitude than ASM engines.

The advantages of C3 injection for the Fw-190s were canceled by A-7's and A-8's heavier weight, and the fact that BMW-801 was featuring only a single-stage supercharger. So the 1944 Antons were fine with C3 injection at ~20000 ft, however, for higher altitudes, where they are likely to encounter the 4 mots and escorts, it still does not help them.

I absolutely agree in that.

 

[gjs238]

Lieutenant William Roach was flying P-47D-2-RA 42-22490 on November 7, 1943. The 355th had delayed return home because the 352nd FG was late getting to R/V. As a result, hampered by 90kts headwinds, three 355th pilots ran out of fuel. Two near Liege and one in the Channel. Roach's YFU "Beetle" spent the rest of the war in Rosarius Zirkus

Too bad he couldn't destroy the plane before it was captured.

 

[drgondog]

Too bad he couldn't destroy the plane before it was captured.

He and his flight leader strayed off course. 10/10 cloud cover. When they were about out of fuel they believed they were over England and landed in a field - Walter Kossack belly landed and Roach landed wheels up. The field was occupied by German soldiers. That Jug survived the war. Both POW's also survived but the pilot who bailed out off the coast (F/O Watson) did not turn up. He was reported POW in January 1944 but never heard from again.

 

[tomo pauk]

They were out earlier, by spring of 1944 (March-April I believe), so just couple of (critical) months later than the first P-47 conversions. Non-ADI AS machines appeared perhaps earlier, they were tested in the automn of 1943 already and entered production by the end of the year.

The availability of AS/ASM machines seem to deserves a thread on it's own? The chart I've posted further down (ASM, despite the AS caption) was made in June 1944, that of course does not mean one or two staffels did not have those earlier

OTOH I do not believe either at all that suddenly all P-47 just had paddle props and ADI goodstuff overnight. Such things need months.. They may have started it in December, but probably took many months. Apart from that, a new prop and a bit more power did not do away with seven tons of take off weight... the P-47 suffered less at altitude at others, but it was far from nimble.

The installation of new prop and WI gear was far easier thing than producing the new engines. The R-2800 in P-47 have had the provision for WI from P-47C-5, ie. late 1942. The power-to-weight ratio at take off meant nothing for every day tasks of P-47, and yes, they were nimble where it was needed.

In fact they arrived just at the same time as Mustangs and improved P-47s...

Here we disagree.

Of course they could, the AS machines were good at altitude.

We again disagree. The chart compares the ASM with P-47 (2300 HP, red line), data for P-47 is from Williams' site.

MEMORANDUM REPORT ON
P-47D-10 Airplane, AAF No. 43-75035

653 km/h at 6100 (20 kft)
678 km/h at 7620 (25 kft)
697 km/h at 9144 (30 kft)
692 km/h at 10060 (33 kft)

In the meantime, a considerable number of GM-1 G-6s and G-5s were produced, though I am not sure how regularly they were employed with boosters in late 1943..

We, again lack the decisive numbers here?

The P-51 had what exact magic property over 25 000 feet? Its engine was no better, perhaps even worse (-7) at altitude than ASM engines.

You know perfectly well that magic of the P-51 was the low drag, plenty-of-fuel airframe, along with two stage Merlin. So even if the engine was not making 2000 HP, the low drag was there to enable good turn of speed.

added: the chart posted here gives even less speed for G-14ASM, some 10 km/h less, plus another drop once the MW-50 is turned off at 9 km.