F4U in Europe

[Schweik]

How much does lift coefficient vary between Spit, F6F, F4U, Bf 109, P-51 etc.? How much of a difference does it typically make compared to Wing Loading?

The Soviets always made a significant distinction between 'horizontal' (turns) and vertical (loops etc.) maneuvering, and rated aircraft according to these factors. The latter has to do with climb rate.

Every anecdotal account I know of, and every test seems to place the Spitfire V, VIII or IX as a superior turner to almost any other aircraft it was compared to, with the exception of the A6M and Ki-43, and as previously noted here Spitfire (like several other Allied types) could out-turn A6M in high-speed turns. Not sure about the Ki-43 on that specific.

The issue of using flaps in turns is significant of course. Many aircraft had maneuvering flap settings, like Bf 109s I believe did, some had automatic maneuvering flaps like the Ki-43 and N1K1. From what I understand, most US Navy aircraft including specifically F4F and F6F, had flaps which could not be deployed above a certain speed, and which would automatically close. The Spitfire also seemed to have only two flap settings from what I remember reading - basically landing or up. They seemed to have such a turning advantage over German fighters that a combat flap setting wasn't thought necessary. The preferred strategy for dealing with Japanese fighters also tended against trying to improve turn rate.

The other factor in turns is power, which you can measure in power to weight ratios.

I was surprised to learn how relatively poor the roll rate for the F6F was. I always had a pet theory that most really successful fighters had pretty good roll. Maybe I need to rethink that.

Here are 'standard*' wing loadings and power / mass ratios for several fighters under discussion. Obviously this is very 'back of the envelope', it's just meant a kind of quick reference.

Fighter ------ Weight*----- Wing Area ---- Wing Loading ---- Horsepower --- Power Loading ---- Full throttle height (Not certain about these numbers)
F6F-3 -------- 12,500 ---------- 334 ----------- 37.4 --------------- 2000 ----------- 0.16 ------------------ 22k
F4U-1 ------- 12,000 --------- 314 ----------- 38.2 --------------- 2000 ----------- 0.17 ----------------- 22k
Spit V -------- 6,400 ---------- 242 ----------- 26.4 --------------- 1478 ----------- 0.23 ----------------- 20k
Spit V (Clipped)6,400 -------- 231 ------------ 27.7 -------------- 1478 ------------ 0.23 ----------------- 18k
Spit IX -------- 7,200 ---------- 242 ----------- 29.7 --------------- 1600 ------------ 0.22 ----------------- 25k (and 14k)
P-51C --------- 9,000 ---------- 235 ----------- 38.2 --------------- 1490 ----------- 0.16 ----------------- 25k
P-51D --------- 9,500 ---------- 235 ----------- 40.4 --------------- 1560 ----------- 0.16 ----------------- 25k
BF109G2 ------ 6371 ---------- 177 ----------- 35.9 --------------- 1450 ------------ 0.22 ----------------- 22k
Bf109G6 ------ 6940 ---------- 177 ----------- 39.2 --------------- 1550** ---------- 0.22 ----------------- 25k

Fw 190A5 -----9700----------197--------- 49.2 ------------ 1800 --------- 0.18 -------------- 19k

* for weight I put combat weights I found on WW2Aircraft performance. This is supposed to be 'normal combat weight' not max gross.
Mustang on wing area I saw 233 or 235, I'm not sure which is right.

** G-6 has 1800 hp under MW/50 boost from what I understand, which makes power-weight of 0.25

Clipped wing Spitfires seem to have only marginally heavier wing loading but anecdotally, they didn't turn as well from what I understand.

Added Fw 190

 

[Schweik]

Greetings VA 5124,

This is a provocative topic and has come up before on the forum. Here are a couple links to earlier threads:

Corsair and Hellcat in Europe

The Chance-Vought (actually Vought-Sikorsky ... all the drawings start with "VS" anyway) F4U Corsair gave the Japanese a nasty surprise. I was a very good fighter and, in its later versions, was simply outstanding by any measure of success of fighter prowess. What do you think might have...

ww2aircraft.net

Was the corsair as good a fighter as the spitfire or the FW?

I was reading this article about best fighter aircraft. Here it is http://home.att.net/~historyzone/F4U-4.html Chance Vought's F4U-4 came about as a development of the F4U-4XA, which was first flown in early April 1944. It was fitted with an up-rated Pratt Whitney R2800-18W or -42W...

ww2aircraft.net

My feeling is that the Corsair would have equalled or bettered potential opposing Axis fighters within its best operating envelope below 20,000 ft. While you mention the ETO, I suspect that the F4U-1 would have had great value in the MTO during the North Africa, Sicily, Italian campaigns especially in CAS and TAC. If the F4U had found its way to extensive use in the MTO/ETO I'm certain that we would have seen a variant appear that embodied the weight savings and performance modifications applied to Marine Corsairs in the Pacific. Ultimately, if the Corsair were being used as a strictly land based fighter, you would see a new non-folding wing further lightening and improving the basic design. (I was looking for a citation here, as I recall seeing reference to this proposed for Marine aircraft.)

The Corsair was an outstanding combat aircraft an assessment that is reinforced by the fact that it was produced well after the war and was used in Korea with distinction.

I think it would have been an outstanding air superiority fighter for the MTO, better than what they were using (Spit V, P-40F, P-38G/H)

The 109Fs and (early) Gs weren't super high altitude performers either, it seems like the F4U could keep up with them if it's still doing over 380 mph at ~25k

The DAF had plenty of good fighter bombers for that role.

 

[FLYBOYJ]

. It's an interesting issue about stringing the ailerons to 10 vs 12 or 15 degrees.

You "string" model boats, you "rig" ailerons.

 

[Schweik]

You "string" model boats, you "rig" ailerons.

I stand corrected.

From this 1944 test, it seems like the F4U-1 could do well over 400 mph at 26,000 ft at Military power

http://www.wwiiaircraftperformance.org/f4u/17930-level.jpg

I assume that means no water injection. Weight listed is 12,162 lbs which is like 'beginning of a sortie' in a fighter configuration.

And still doing over 420 mph at 23,000 ft at WEP (with water injection)

That obviously is very good.

Interesting that the Boscombe down test seems to show far lower performance, but they seem to be using a fairly low power setting 32.8" (or are they referring to something else?)

This test shows it at 388 mph at 24,000 ft, I think that is still quite competitive with anything else flying around the MTO in 1943 - mid 1944

 

[BiffF15]

I might also remark that Very Few Warbird pilots today even Know that P-51B/D are rigged for 10/12 and 15 degrees and are flying the Merlin Mustang at 10 degrees for ailerons. My father flew both 12 and 15 during WWII. Four of six 109s and one Ju 87 were shot down in contested manuevering fights, including on the deck with no real margin for error. I know that the P-51D that Corky Meyer flew in his comparisons was a D with only 10 degrees aileron rigging and also had Reverse Rudder Boost tabl installed - rendering that D to diminished manueverabilty against even a P-51A.

Bill,

I apologize in advance if I've asked this before. Would you please explain what you are referring to by 10, 12 and 15 degrees on the ailerons. I'm assuming it's how much aileron you get per inch of stick travel or how much total aileron you get with max lateral deflection of the stick.

Also please explain why current warbirds are flown at 10 vice the other two settings.

Mucho Gracias,
Biff

 

[drgondog]

Bill,

I apologize in advance if I've asked this before. Would you please explain what you are referring to by 10, 12 and 15 degrees on the ailerons. I'm assuming it's how much aileron you get per inch of stick travel or how much total aileron you get with max later deflection of the stick.

Also please explain why current warbirds are flown at 10 vice the other two settings.

Mucho Gracias,
Biff

Aileron deflection setting for max throw. 10/12 or 15 Degrees. I still haven't found out what the factory setting was in 1943-1945 as deleivered - but believe 15-
IIRC the USAF re-set to 10 degrees post war and many P-51s that went into civilian market were at 10. Of all the Warbird piots I know, only John Muszula II was aware before I mentioned it - and flies his B/D Mustangs at 15. I think he is rigging dada's rebuilt P-51D-20-NA 44-72253 WR-B JANE VI at 15 degrees.

 

[pbehn]

You "string" model boats, you "rig" ailerons.

You also string guitars, at some stage you must string race horses because I am told they are highly strung.

 

[Schweik]

I know there was a problem with the ailerons on the early NA-73 / A-36 / P-51A Allison-engined types, and I think that was actually the issue, which they addressed with the first Merlin types.

 

[drgondog]

I stand corrected.

From this 1944 test, it seems like the F4U-1 could do well over 400 mph at 26,000 ft at Military power

http://www.wwiiaircraftperformance.org/f4u/17930-level.jpg

I assume that means no water injection. Weight listed is 12,162 lbs which is like 'beginning of a sortie' in a fighter configuration.

And still doing over 420 mph at 23,000 ft at WEP (with water injection)

That obviously is very good.

Interesting that the Boscombe down test seems to show far lower performance, but they seem to be using a fairly low power setting 32.8" (or are they referring to something else?)

This test shows it at 388 mph at 24,000 ft, I think that is still quite competitive with anything else flying around the MTO in 1943 - mid 1944

This is a Specification with stated performance utilizing the P&W R-2800-8 (no water injection). Military Power for this airplane/engine is 2000HP at 54. MP at take off.

 

[drgondog]

I know there was a problem with the ailerons on the early NA-73 / A-36 / P-51A Allison-engined types, and I think that was actually the issue, which they addressed with the first Merlin types.

All Allison Mustangs were rigged at 10 degrees, The test ship for A-36 AM-118 had the first 15 degree rigged aileron, the XP-51B was so rigged and all Merlin P-51B/C/D/K were so rigged for +/-10, 12 qnd 15 degree. The XP-51F/G/J/H were rigged with +/- 10 only but each had ~10% more aileron area.

The changes were instigated at both NAA in spring 1942 as well as NACA Langley on the XP-51 41-038 (#1), and implemented on AM-118 in June/July 1942.

 

[Schweik]

B/C/D had the same aileron size as P-51A / NA 73 / A-36?

 

[NTGray]

You "string" model boats, you "rig" ailerons.

Ignorant, naive, but genuine question:
Since a ship has "rigging" and a submarine "rigs" for dive, your statement seems backward to me. Or at least halfway backwards, since I don't know any comparable references for airplanes. Can you expound further?

 

[pbehn]

Ignorant, naive, but genuine question:
Since a ship has "rigging" and a submarine "rigs" for dive, your statement seems backward to me. Or at least halfway backwards, since I don't know any comparable references for airplanes. Can you expound further?

Rigging is both a noun and a verb.

 

[DerAdlerIstGelandet]

Ignorant, naive, but genuine question:
Since a ship has "rigging" and a submarine "rigs" for dive, your statement seems backward to me. Or at least halfway backwards, since I don't know any comparable references for airplanes. Can you expound further?

Its called "rigging" when you adjust the flight control cables. You adjust them to a specific tolerance, such degrees of upward or downward, or left to right movement.

You "rig" ailerons, trim tabs, rudders, and elevators. You utilize "rig" pins and adjust turnbuckles for example to "rig" the flight control system.

 

[DerAdlerIstGelandet]

Rigging is both a noun and a verb.

Ding, ding, ding…

Tell pbehn what he's won Vanna!

 

[pbehn]

You string a toy boat with string because it is a toy boat, the string is decorative, because the main mast wont snap without it. A ships rigging was of tarred rope, shackles, capstans, block and tackles and other "stuff". When all this was made ready it was rigging the ship and when completed it was rigged. But there were many ways to rig a ship, to set sail, for light winds, for trade winds or for a storm. This is why people can claim elections and sports matches are rigged as well as aircraft.

To complete the pedant's revolt, all submarines are boats, not ships.

 

[FLYBOYJ]

Ignorant, naive, but genuine question:
Since a ship has "rigging" and a submarine "rigs" for dive, your statement seems backward to me. Or at least halfway backwards, since I don't know any comparable references for airplanes. Can you expound further?

You "rig" aircraft by adjusting control surfaces that may be actuated by cables or pushrods and in doing so you use rig boards or a dial protractor to acquire the correct deflection of the control surface being rigged.

Sorry if image is upside down

 

[NTGray]

To complete the pedant's revolt, all submarines are boats, not ships.

Now, that I already know. The rest of it was good info. Learned something today, from you and the others. Thanks.

 

[pbehn]

Now, that I already know. The rest of it was good info. Learned something today, from you and the others. Thanks.

I also just thought, use of the terms "string" and "stringing" may have been discouraged when longerons and "stringers" became part of an aircraft structure.

 

[GrauGeist]

In the early days of aviation, many naming conventions were applied from the nautical realm as the technology evolved.
Vertical control surfaces were "rudders", they had "rigging" (a term from sailing ships, which were still in use at the time), the left side was "port" and the right was "starboard" (the red and green marker lamps were eventually applied as time went by), groups of aircraft were called "squadrons" and even some nation's air groups were called "flotillas" early on.