P-47: We could easily out-turn the Jerry

[HoHun]

Hi Widewing,

>The P-47s typically didn't reach their best speed until 32,000 ft. Up there, they out-climbed, out-turned and easily out-ran the 190A and 109G-6 subtypes they generally encountered. Even later German fighters, such as the 190D-9 and 109G-10 fell short in performance up that high.

True. The Dora only got competetive with the Jumo 213E, and only a handful of these were actually installed. The Me 109 probably was in a better situation since it was very light and I'd expect it to be competitive in climb, but there's no doubt the P-47 was an excellent performer.

I'd love to see an actual wartime test report, though - I have seen only two data sets for the P-47 (F4U-4 comparison and AHT's chart), and I think both are simplified. The AHT chart actually looks a bit more convincing - maybe it's just that I haven't fully understood things.

>Mustangs performed better at medium altitudes (15k to 25k).

Yes, that's a direct result of replacing the V-1650-3 with a V-1650-7. It has been claimed that medium altitude performance was more useful than high altitude performance, but I'm still not sure whether I should believe that :-)

Regards,

Henning (HoHun)

[Angus]

Hehehe, Merlin 61 equipped Spitties cruising at 43K in late 42 probably beat the lot.
Must have been uncomfortable though....

[Glasses]

I agree the Juggie out performed the LW fighters aboive 25k. Below 20k it was a different story, however I think AH is a bit too generous in the lo alt handling of the Jug, but whiskey tango foxtrot .

Hoepfully when the twittlers get the unfockring maybe we shall something better I don't expect it though.


BTW if you're going above 30k why the hell are you going in a G10 or D-9 what's the Ta152 for?

I remember back a couple of months ago or maybe a year can't remember  I saw ammo and a wingman trying to bounce me and I was going about 300indicated and I out zoomed them.

everytime they repositioned themselves I out zoomed them again and again. Yet I got some hits I didn't kill either.

[bunch]

Originally posted by Angus
Hehehe, Merlin 61 equipped Spitties cruising at 43K in late 42 probably beat the lot.
Must have been uncomfortable though....

IIRC, WingCo (formerly S/L) Lyne Shute put something about that in his autobiography

[Kurfürst]

Originally posted by Widewing
P-47C-5-RE, circa April of 1943: 433 mph at 30,000 feet. It's a whole lot faster than what the Luftwaffe had to oppose it at the time. Toothpick prop too....

Check data chart 30 in Dean's America's Hundred Thousand, page 278.

I`ll check out it, when I find those curves...
But I doubt the toothpick prop, if it`s already so fast, how could it be equally fast with the paddle paded one? No improvement at all? unlikely...

Meanwhile you check out this :



No Gm-1 or such. That would give *some* (+120km/h) extra at high altitudes for the Gustav.

[tikky]

P-51 IS THAT SLOW???????????????????????????????????????????????????????????????????

NOW THAT TEST IS RIGGED!

[gwshaw]

Originally posted by tikky
P-51 IS THAT SLOW???????????????????????????????????????????????????????????????????

NOW THAT TEST IS RIGGED!

It is an Allison Pony, not a Merlin one. But, even at that is probably about 30 km/hr to slow.

Greg Shaw

[Widewing]

Originally posted by Kurfürst
I`ll check out it, when I find those curves...
But I doubt the toothpick prop, if it`s already so fast, how could it be equally fast with the paddle paded one? No improvement at all? unlikely...

Listen, there's a wealth of data on the P-47, all of which establish it performance without question. Toothpick prop or paddle-blade, speed remained unchanged. Climb, however, was considerably improved with the high-activity prop. Meanwhile, I'll go with the data out of Langley and Eglin.

My regards,

Widewing

[HoHun]

Hi Widewing,

>Listen, there's a wealth of data on the P-47, all of which establish it performance without question.

Do you have a set of data which lists speed, climb and power/critical altitude for one specific aircraft along with the weight? In analyzing P-47 performance, I have only found partial sets so far, which were partially contradictory.

Regards,

Henning (HoHun)

[HoHun]

Hi again,

I've found the following engines listed for the major P-47 variants:

R-2800-21 for P-47B/C
R-2800-21W for P-47D
R-2800-51W for P-47D
R-2800-59 for P-47C/D
R-2800-63 for P-47D
R-2800-57(C) for P-47M/N
R-2800-77 for P-47N

Power seems to have been either:

2000 HP
2300 HP
2535 HP (contradictory mentions)
2600 HP (only in F4U-4 report)
2800 HP "C" engines

The "C" engine is rated:

2600 HP @ 63" Hg at 2800 rpm, critical altitude 27000 ft (climbing)
2800 HP @ 68" Hg at 2800 rpm, critical altitude 24500 ft (climbing)
3000 HP @ 73" Hg at 2800 rpm, critical altitude 22000 ft (climbing)

Does anyone have a clue which engine produced which power rating in which subtype? It all seems very confusing from internet sources.

Regards,

Henning (HoHun)

[Rino]

I know this is annecdotal, especially since I cannot remember
the book I read it in, but the Jugs were able to use a "trick" to
outturn 109s and 190s as well.

     It was called the lag pursuit roll, basically you roll opposite
the bandit's turn 270 degrees, then pull in behind him using
your elevators.  Because it allowed more seperation between
the aircraft, the P-47 was able to slow a bit and turn inside
the german aircraft.

[bozon]

Johnson claims his D-5 was boosted up to 72". I wonder how it translates into HP. If it's anything resembling the "C" figures posted here than it would be 2800-3000 HP !

That would give his jug some crazy preformance for a 1943 early 44 plane. I can almost hear the whines had the AH D-11 would have a paddle blade prop and 600HP to spare.

Bozon

[Kweassa]

475mph at over 35k, IIRC Johnson's last interview.

 IIRC also Hohun's theory, it is highly likely a misreading due to pitot tube problems.

[BaDkaRmA158Th]

No,its most likely due to him being pushed WITH the wind flow.

[Kurfürst]

Originally posted by gwshaw
It is an Allison Pony, not a Merlin one. But, even at that is probably about 30 km/hr to slow.

Greg Shaw

It`s an actual test afaik, and results are what they are. Certainly quite a few P-47s were received by the Red Air Force, and they tested them of course. I`d like to see some evidence to the contrary, because it`s seems to me very unlikely that despite the stronger engines, better propellors, etc., the speeds were the same in 1942 as in 1944. All sources I have seen so far shows the early P-47s at 663kph max.