F4U-4 vs YaK-9U

[Soren]

Been a long time since we one of these excellent debates, so we'll start with te below



F4U-4 vs Yak-9U

So which one is the best ? And in a one on one fight with equally skilled pilots which will come out the victor ??

[FLYBOYJ]

Without going into each aircraft's performance specs, I'd give maneuverability to the YAK, speed and probably climb to the Corsair. A four cannon Corsair would demolish a Yak but I think the Corsair would survive a few 20mm rounds from the Yak. Overall I'd take the Corsair.

[DerAdlerIstGelandet]

Im with Joe, but this is ofcourse without looking further into performance, etc.

I dont believe these two aircraft have ever been compared in tests. Is that true?

[Soren]

IMO the F4U-4 is the best, esp. seeing that it's faster, has a higher climb rate and offers allot more protection. As to maneuverability, well I think they're pretty close here, and the F4U-4 should, with 2,800 HP, be able sustain a slightly tighter turn.

[drgondog]

Always hard to make these manueverabilty judgements on paper.

On paper, with no consideration for individual flight characteristics in a hard turn the W/L for the Yak-9U is close to 38#/ft>>2 at max weight, while the Corsair is 20% higher at 46.

The Yak-9 had less Hp but a lot less weight. I's power to weight loading is around .2 while the F4U was lower at .15 for max weight.

The F4U-4 had a higher rate of climb and presumably could dive faster - both had excellent speed at 20,000 feet and below, the F4U probably faster at 30,000 feet.

Speculatively the Yak 9 could out turn the F4U and out accelerate it, had less armor and firepower, less range, less high altitude speed and less diving speed.

I suspect the F4U was better in vertical and Yak 9 better in horizontal all pilot skill being equal.

[parsifal]

Some basic stats about each A/C
Yak-9U
Powerplant: 1650 hp Klimov VK 107A V Piston engine
Performance: Max Sp 434 mph at 16000 ft, service ceiling 39040 ft, range 541 miles, initial climb unknown (well, from the one source I looked at
Weights: 5988 lb (empty), max T/O weight 6830 lb
Dimensions: span 32.25 ft, length 28.5 ft, Wing area 185 ft
Armament: 1 x 20 mm MP-20 Cannon and 2 x 0.5 in UBS MG
F4U-4
Powerplant: 2250 Hp Pratt & Whitney R-2800 Double Wasp Radial
Performance: Max Sp 415 mph at 19500 ft, service ceiling 34000 ft, range 1562 miles, initial climb unknown (well, from the one source I looked at (same as the Yak)
Weights: 9100 lb (empty), max T/O weight 12100 lb
Dimensions: span 39.75 ft, length 33.33 ft, Wing area 305 ft
Armament: 4 x 0.5 in Browning MG

At a guess I am going to say the Yak can outclimb the F4U, but the wing area (which surprised me), probably means the Corsair out turns the YAK. I
also believe that the Corsair will outdive the the Yak. The Yak appears to have the altitude advantage. Speed is also slihtly in the YAKs favour. There is very little to choose from in terms of the firepower each plan can generate, but the much heavier weight of the Corsair suggest that it has the ability to absorb a much greater amount of punishment.

Tentatively, I would back the Corsair, but its much closer than I had thought

[marshall]

I think that there are some mistakes in the stats posted by parsifal.
F4U-4 max speed is rather closer to 450mph at alt than 415mph and it had 4 20mm cannons or 6 .50s. Initial climb rate around 4800fpm.

I voted for Corsair.

[FLYBOYJ]

parsifal - your source for the Corsair's armamant - 4 x 0.5 - try 6 or 4 20mm.

From Wiki...

F4U-4
Performance
Maximum speed: 446 mph (388 knots, 718 km/h)
Range: 1,005 mi (873 nm, 1,618 km)
Service ceiling 41,500 ft (12,649 m)
Rate of climb: 3,870 ft/min (19.7 m/s)

Yak-9U
Performance
Maximum speed: 417 mph at altitude (672 km/h)
Range: 420 miles (675 km)
Service ceiling 35,000 ft (10,650 m)
Rate of climb: 3,280 ft/min (16.7 m/s)

[buzzard]

I only checked one of my references, and it gave the Yak an initial climb rate of 4528 fpm. The F4U-5 (yeah, I know...) initial climb rate was 3780 fpm. The other specs corresponded closely with parsifal's.

Given this, and what the experten had to say about the agility of the later Yak-9s, I'd probably put my money on the Yak in a classic dogfight. The Yak may not have had impressive firepower, but a lot of Corsairs were splashed by the similar armament of the Zero.

As an all-round combat AC, I think the Corsair was far superior.

I'm leaving for my fishing trip, so I won't be responding for a few days. I'll be too busy fending off the aerial attacks of the dreaded blackflies

JL

[buzzard]

FBJ,

Just saw your post. Quite the discrepancy in the RoC for the Yak. My specs are from Jane's.

Gotta go find my hip waders...

[renrich]

Michael, the performance figures that FB posted are those for F4U4. Your's are probably for a F4U1a. I don't know which Yak 9 it was or who was flying them but, if memory serves, F4Us met Yak 9s in early going in Korea and shot them all down.

[JoeB]

I dont believe these two aircraft have ever been compared in tests. Is that true?

A North Korean Yak-9P, all metal but basically similar performance to a U, was captured in Korea in September 1950 and tested in the US, but not in head to heads AFAIK, performance of prop planes probably wasn't such a hot issue by then.

Also the the types, F4U-4 and Yak-9, very likely Yak-9P's, met in one daylight combat in Korea April 21 1951. A pair of VMF-312 F4U-4's, one piloted by Phillip DeLong, already an ace from WWII, claimed at least 3 of 4 Yak-9's that jumped them when they were carrying external stores, for some holes in one of the F4U's. The NK side of that combat isn't known but one Yak and its pilot's body were recovered from shallow water nearby. Of course it's only one incident and 'pilots equal' was highly unlikely to have been the case.

Another Yak-9 was claimed in a night action by an F4U-5N whose Marine pilot also already had (F6F-5N) victories in WWII.

Joe

[kool kitty89]

The Corsair also used the High lift NACA 23000 series airfoil (common to the F4F, F6F, F2A, Fw 190, and portions of the P-38 and P-39, all of the Mitchel wing P-3 with 15% thickness at root, 9% at tip. (CLmax decreases with thickness over 16% for this airfoil) The CLmax for the corsair's wing was nearly 1.6 iirc.

The Yak (and almost all soviet fighters) used a modified Clark Y airfoil (YH), the same as the Hawker Hurricane, which is a relatively simple design. (less lift or drag efficient than the NACA airfoils used, though better than the simple Clark Y) With thickness 14% at the root and 10% at tip. I don't have figures for CLmax, but I'd imagine it would be somewhere around 1.3-1.35.

The Incomplete Guide to Airfoil Usage

The AR of both a/c is very similar. (slight edge to the Yak, along with a high taper ratio)

Consdering the airfoil difference they should be about equal in lift loading.

Power loading at low alt goes to the Yak with 1,500 hp for the ~7,000 lb gross weight, compared to 2,450 hp for the F4U-4 (water injection) with 14,000 lbs gross weight.

But if you reduce the fuel load of the F4U to be the Yak's range it would be much closer, along with even better wing loading.

Of course actual aerodynamic test results would be needed to fully clarify the characteristics)

Armament of the F4U is good with 6x .50's with 420 rpg giving heavy firepower for a long firing time. (at 800 rpm ~31 sec) Able to easily tear the Yak apart, while even with the 20mm the Corsair would take a good pounding. I don't consider the 4x 20mm Corsair, as 1. there weren't a whole lot of them made, but more importantly 2. they had freezing problems at altitude, and 3. the 20mm M2 cannon was still not that reliable of a gun. (much better than the M1, but not close to the British Mk.2 Hispano, or the Soviet ShVak or B-20)

The F4U-4 also had an excellent roll-rate at over 100 degrees/s (similar to the P-47N).

[FLYBOYJ]

FBJ,

Just saw your post. Quite the discrepancy in the RoC for the Yak. My specs are from Jane's.

Gotta go find my hip waders...

My numbers were from Wiki and its what they had posted for the F4U-4, I don't rely too much on Wiki but from I seen elsewhere they seem about right.

[parsifal]

it was 5 am down here....was barely functioning at the time