Fury/Sae Fury , Corsair, Mustang and MB5

[PMN1]

How did the Hawker Fury (Griffin and Sabre engined prototype versions as well as the actual Centaurus version) and Sea Fury compare to the Vought Corsair (F4U-4 version on) in terms of overall performance at the time and possible development had jets not superseded them.

Similarly how did the Martin Baker MB.5 compare to the P-51 Mustang (from the D version on).

How do all the types compare to each other?

[Ricky]

PMN1 -

Hi, and welcome!

without wishing to sound rude...
Several of the questions you have asked have already been addressed in other topics - I would advise you have a bit of a read-through (admittedly it will take a while...)

Also, as the site only shows a limited number of topics on a page, maybe you could group your questions into fewer topics?

Please don't be put off joining in - I'm just being pernickety!
;)

[Corsarius]

Hi PMN1. You've asked some interesting questions, but I have to agree with Ricky.

No spam, please! I don't think Taglia will take it too kindly, even though your questions have much merit. Perhaps you could regroup them into a single post that we can all address, then remove your others for the benefit of the forum?

[PMN1]

Editing in progress - but it doesn't seem to have reduced the number of posts much!!

[GregP]

Hi PMN1 and welcome.

The Sea Fury was a 1945 airplane while the Corsair was an earlier airplane. Basic comparison looks as follows.

Sea Fury Mk II: 1849 kW, 4193 kg empty, 5672 kg normal gross, 218.1 kg. / sq. m wing loading, 3.1 kg / kW power loading, 740 kph max speed, 1316 mpm rate of climb. 4 x 20 mm cannon.

Corsair F4U-4: 1752 kW, 4238 kg empty, 6592 kg normal gross, 226 kg. / sq. m wing loading, 3.8 kg / kW power loading, 684 kph max speed, 1180 mpm rate of climb. A 1943 airplane. 6 x 12.7 mm MG or 4 x 20 mm cannon.

So basically, the Sea Fury was a bit bigger and heavier, but perhaps turned slightly better, climbed slightly better, and was a bit faster. If the Corsair had the cannons, armament was the same. The Sea Fury could deliver 900 kg of bombs wjile the Corsair could dceliver 725 or so.

In all catgegories the Sea Fury appears just a bit better than the F4U-4, but that is on paper only. How they really stacked up against one another is a guess. They were probably close enough so that the "better" plane depended on the pilots at the time of employment.

The MB-5 versus Mustang is another story.

MB-5: 1719 kW, 4192 kg empty, 4994 kg normal gross, 204.4 kg./ sq. m wing loading, 2.9 kg / kW power loading, 740 kph top speed, 1158 mpm rate of climb.

P-51D: 1111 kW, 3176 kg empty, 5263 kg normal gross, 241kg. / sq. m wing loading, 4.1 kg / kW power loading, 708 kph top speed, 1060 mpm rate of climb. 907 kg bombs.

P-51H: 1029 kW, 2988 kg empty, 5016 kg normal gross, 231 kg. / sq. m wing loading, 3.1 kg. / kW power loading, 784 kph top speed, 1113 mpm rate of climb. 907 kg bombs.

So the P-51D appears to be the bottom of the heap of three, with the MB-5 in the middle, and the P-51H appears to be faster, climbs better, and hauls some bombs (can't say for the MB-5 ... they never got that far in testing).

Also, the MB-5 had a complex contra-prop that might or might not have been OK in combat. It had cannons while the P-51s had 6 x 12.7 mm MG armament.

All in all, the MB-5 looks on paper like a good plane that was right with the P-51H and slightly better than the P-51D. Again, they are all pretty close in employment, but the MB-5 looks to be able to out-turn either P-51 by a slight margin. None of them were able to turn with a Spitfire.

[BuzzLightyear]

quote:Originally posted by GregP

Corsair F4U-4: 1752 kW, 4238 kg empty, 6592 kg normal gross, 226 kg. / sq. m wing loading, 3.8 kg / kW power loading, 684 kph max speed, 1180 mpm rate of climb. A 1943 airplane. 6 x 12.7 mm MG or 4 x 20 mm cannon.



Those look like F4U-1 specs, not F4U-4 performance specs.

F4U-4
Powerplant: Pratt and Whitney R-2800-18W
HP: 2,450 hp (combat power/wet) (1,827 kw)
Weight: 12,480 lbs in fighter loadout (5,660 kg)
Wing area: 314 sq feet (29.17 m sq)
Power loading: 5.09 lb/hp (3.10 kg/kw)
Wing loading: 39.75 lb/sq ft (194.03 kg/ m sq)

Top speed: 452 mph (727 km/h) @ 21,000 feet

Rate of climb:
4,770 fpm @ sea level (1,454 mpm)
4,810 fpm @ 10,000 feet (1,466 mpm)
4,250 fpm @ 15,000 feet (1,295 mpm)
3,800 fpm @ 20,000 feet (1,158 mpm)
2,000 fpm @ 30,000 feet ( 609 mpm)

4.9 minutes to 20,000 feet.

In my estimation, the F4U-4 is a little slower, but climbs significantly better, and probably turns as well if not better.

The F4U-4 should be considered a 1945 aricraft. It was evaluated in November 1944 at the Joint Figher Conference, but did not see combat until the Okiunawa campaign in April 1945.

[GregP]

Hi Buzz,

My specs come from a couple of places. What is your source?

I am not claiming you are wrong, only asking for the source. I have been wrong enough times in this forum already! [B)]

OK ... I looked it up again.

I show 446 mph, not 450. And I show 3870 fpm rate of climb. These figures are, of course, military power ... not war emergency power. Any plane that used WEP needed and engine change when it got back to base, and it wasn't used very often. So, my feeling is that the WEP performance figures were just that, emergeny resouces.

Also, many people claim the Corsair, particularly the F4U-4, was the best bomb carrier of the war.

I say the Sea Fury was. The numbers certainly favor the Sea Fury.

The real question is, "Does the Sea Fury qualify as a WWII airplane?" I say yes ... though jusy barely.

[Paolo Tagliaferri]

quote:Originally posted by Corsarius
No spam, please! I don't think Taglia will take it too kindly
I just think that it would have been better if he didn't post all the questions in a single row :D
BTW I think that this is not really SPAM, but a bad usage of the forum ... anyway since it seems to me that he understood this I think there will not be many problems anymore.

P.S. my english is really awful :D It will be better when I will do my english exam for the university (somewhere in next 6 months) ... :)

[Ricky]

Taglia,

I work at a University in England -
your English is better than most of our British students, let alone our students from 'overseas'.

Please do not apologise for it!

[BuzzLightyear]

quote:Originally posted by GregP

Hi Buzz,

My specs come from a couple of places. What is your source?

I am not claiming you are wrong, only asking for the source. I have been wrong enough times in this forum already! [B)]

OK ... I looked it up again.

I show 446 mph, not 450. And I show 3870 fpm rate of climb. These figures are, of course, military power ... not war emergency power. Any plane that used WEP needed and engine change when it got back to base, and it wasn't used very often. So, my feeling is that the WEP performance figures were just that, emergeny resouces.

Also, many people claim the Corsair, particularly the F4U-4, was the best bomb carrier of the war.

I say the Sea Fury was. The numbers certainly favor the Sea Fury.

The real question is, "Does the Sea Fury qualify as a WWII airplane?" I say yes ... though jusy barely.


A couple of sources:

1) WEP Horsepower: The American Fighter Enzo Angelucci, page 443

2) Dimmensions: America's Hundred Thousand Francis Dean, page 508

3) Performanc Data: Naval Aviation News / May - June 1986 / F4U Corsair article by Harold Andrews, page 28

http://members.cox.net/rowlandparks/dash4_1.jpg

http://members.cox.net/rowlandparks/dash4_2.jpg

[Corsarius]

Taglia, I live here in Australia, and you speak English as well as most people I know and work with. Don't worry about it. I'd say that if you fail your English course, it's because your lecturer can't speak Italian.[:p]

[GregP]

Hi Buzz,

Thanks for the sources.

I don't believe that rate of climb graph was done at gross weight and military power. The power loading doesn't support it very well except at war emergency power which, again, was not to be used except in dire emergencies, or at a raduced weight. Looks like a good "wish graph," though.

Also, I have not located any other source that says it went 393 knots. Most are 5 - 8 knots slower. Not a lot, I admit.

Nothing against the Corsair, but it just wasn't quite that good in service. Ask the pilots who flew them. I have and they weren't.

The Sea Fury was a better fighter, but came later than the F4U-4. It carried more ordnance and was faster. However, if you'll check my post above, I DID state that in real life, there was little to choose between them in effectiveness. Both were at or near the top of their game.

[BuzzLightyear]

Well, it's not a "wish graph." It's true performance taken from flight testing. The weight is listed.

Your speed is clearly for a plane with zero-length rocket rails.
Per that report I posted, "Addition of 8 MK5-1 lauchers decreases Vmax at s.l. of condition (2) to 318 knots and Vmax/ACA to 384 knots/20,400 feet."

Whether or not the Sea Fury was better is a subjective call. However, I disagree that the Sea Fury is a WWII plane. It didn't fly until early 1945. I don't think it made it into service until 1946. And I know it wasn't approved for carrier service until 1947. In 1947, we should be comparing to the F4U-5, which was faster and more performant yet than the F4U-4.

[GregP]

Perhaps you are right and we shouldn't be considering the Sea Fury at all in a WWII discussion. I can't say with any certainty, so I'll bow to your proposed timetable.

I also won't argue the performance of the F4U-4 any further, but we all have our own opinions. Mine are already stated, as are yours.

In my sources, the configuration of the aircraft that generated the quoted performance numbers is not given, so I can't say what it might have been. I simply haven't seen a credible spec with the numbers you show ... and I have seen several dozen specs.

Let's just say that you are a Corsair fan, and have found a good source that may or may not be representative of an actual in-service aircraft.

The North Americab P-51D is often quoted as being a 437 mph airplane at a certain height, but that was a standard air corps aircraft. One flown without armament or armament fittings, without drop tanks, with careful attention to fit and finish, at low weight, with gap seals, and with a well-tuned engine and a perfectly balanced and true-pitch propeller might easily have exceeded 460 mph in level flight. They just didn't in general squadron service as delivered from North American.

The Corsair was known far and wide as 430 mph airplane in the later models, so 450 is a stretch for me to believe. In fact, I don't, graph or no graph. But, my opion here is unimportant.

Personally, I flew Cessnas for 6 years, but I can't recall the exact maximum speed of a 1980 Cessna 182 ... and that was less than 15 years ago. Of course, I hardly ever FLEW at top speed, if I ever did at all, so maybe it's not too surprising that I can't recall it.

Cruise speed, now that's another story altogether. I recall that since that's where I spent all my time. Rate of climb varied depending on load (no passengers or all 4 seat full ...) ... and rate of climb ALWAYS depends on load, even in a brand new F-22 Raptor.

Does anyone else out there think the F4U-4 Corsair was 450 mph in level flight?

How about a real live F4U-4 Corsair pilot. Chime in here you Corsair drivers. And don't tell me about a factory-fresh, brand new Corsair that was the pet personal aircraft of the stateside base commander. Tell me about a plane in fleet service for at least 3 months that actually flew operations in the real Navy.

Great fighter, but was it a 450 mph unit that could climb at 4350 fpm? For real? And not need an engine change when it landed? And if it COULD fly that fast, was the configuration one taht could actually carry armament? Or was it as clean as possible and newly waxed after a careful wash and polish job?

[BuzzLightyear]

Apparently the Navy was satisfied it was a 450mph+ fighter that climbed in excess fo 4,350fpm,. Here is another page from a Navy doc I have:

http://members.cox.net/rowlandparks/F4U4CP.jpg

[GregP]

Hey Buzz,

I found a source that claims the F4U-5 could do 470 mph! Unfortunately for me, it is a source I normally trust. Since that is the case, I now seriously wonder why that level of performance wasn't seen in other fighters using the R-2800 engine and propeller combination.

In particular, the Grumman Hellcat used the same R-2800 engine and the same 3-blade propeller as the F4U-1 and, despite claims by most sources to the contrary, Corky Meyer says they had almost exactly the same level performance when flown side-by-side.

So ... this begs the question, did the F6F-5 ever use the same engine and 4-blade propeller combination as the F4U-4 or F4U-5?

I don't know, but will begin looking into it, as well as looking very hard at the rate of climb numbers. I have the idea that, in order to reach 4000+ fpm at military power (no WEP), the efficiency of the 4-blade proper would have had to be well beyond that efficiency seen in other WWII propos ... but I haven't confirmed that yet in calculations.

If it turns out to be true, then it seems other services would have JUMPED on the new prop for their own fighters and bombers right away ... and they didn't. Or maybe they WANTED to ... but saw the handwriting on the wall and decided jets were just around the corner anyway, and so elected not to make the change.

This has been VERY interesting to me. Thanks! I'm not a complete convert yet but, if the 450 mph and 470mph turn out to be real (seems so at this point unless the coefficient of lift is way out of line), then the F4U-4 and F4U-5 would seem to be the best of the WWII fighters that saw service. Maybe this stuff should go into the "Best Fighter" thread?

So, why didn't the F4U-1 go faster and climb better? Hhmmmmmm ...........

What were the factors that made an aircraft of essentially the same design jump its performance by over 12% with a seemingly minor change to the powerplant system? Some part of the powerplant-propeller system got WAY better or the airframe had a very effective aerodynamic cleanup done to it. Maybe both.

This is a whole new thing to look into!Did you notice in your posted summary that the service celing dropped when they went to combat power? That seems interesting and suggests that combat power needed slightly more Oxygen content in the air than Military power did. Probably means that Combat power ran a slightly richer mixture, so the cylincer head temperatures were probably a few degrees cooler than at Military power.

That, in itself, seems strange to me, but maybe so. I have no experience at all with large radial engines being operated at very high power settings. The engine in a T-6 has no WEP at all, and only generates about 600 hp, and so doesn't exhibit this characteristic. Yet another thing to look into when I get time!

[ickysdad]

GregP, Buzz,
Maybe both of you are right. Over on the mustangsmustangs.com website there are some former Mustang pilots who talked about a standard or stock Mustang hitting around 380 MPH at sea level with the engines drawing 61" on Military Power & 67" on WEP.With the advent of 150 octane fuel USAAF Mustangs in Europe were modified to draw 77" on WEP and RAF Mustangs 81".The USSAF one's hit at just a tad over 400 MPH at SL while the RAF one's hit 410 MPH. I don't know if this applies to your all's argument,but it may show that field modifacations could affect performance significantly. Anyway you just got some new info and I think it should be very reliable sine it comes from some former Mustang pilots.

[GregP]

OK, the original Corsair went 404 mph with 2000 hp. Speed goes up with the square of the horsepower, so 25% more power would yeild about a 12% increase in speed.

The square root of 1.25 is about 1.12, or a 12% increase. 12% of 404 mph is about 48 mph, and 48 + 404 = 452 mph.

So, I would expect 452 mph with 2500 hp. The F4U-4 didn't HAVE 2500 hp. It had 2350 hp. That is a power increase of 17.5%, wihic should yield a speed increase of 8.4% (square root of 1.175 = 1.084).

8.4% of 4004 mph is 34 mph, and 404 + 43 = 437 mph, ahich is what I would expoect from 2350 hp. Since they apparently got more, then the new 4-blade prop could account for some of it, but there MUST have been a slight cleanup of the airframe to get 450 mph from 2350 hp.

[BuzzLightyear]

WEP hp for the F4U-4's R-2800-18W was 2,450, not 2,350. I'm not sure how much the -4's airframe was cleaned up. There was a change in the duct work. The oil cooler was moved from the wing roots to the chin. That chin scoop led to the oil cooler. Therefore, there may have been less drag with this set-up than with previous Corsairs. The new four-bladed prop probably helped as well.

The F4U-5's R-2800-32W was a substantially more powerful engine than the -18W in the -4. The -32W made 2,800 hp at WEP.

Greg, you wrote:
This is a whole new thing to look into!Did you notice in your posted summary that the service celing dropped when they went to combat power? That seems interesting and suggests that combat power needed slightly more Oxygen content in the air than Military power did. Probably means that Combat power ran a slightly richer mixture, so the cylincer head temperatures were probably a few degrees cooler than at Military power.

Those are critical altitudes.

In terms of US planes, fighters had four power ratings: Normal, Military, Take-Off and War Emergency. Each had a different critical altitude. Take-off power is always rated at sea-level so we'll leave this rating out.

Normal power, military power and war emergency power all had their own critical altitudes. A critical altitude is the maximum altitude that any given power rating can be maintained. As you know, power decreases as altitude increases. The supercharger compensates for this to a degree, but sooner or later not even the supercharger can maintain rated power.

So, if you are climbing at full throttle, or at WEP, sooner or later you will reach a point where WEP power rating can not be maintained and power begins to fall off. You're still climbing at full throttle, but making less than WEP power. Climb higher and at some point you will only be making military-power. Soon, you are only making normal-power. Soon after that, you can't even maintain normal power. And you are still at full throttle. The maximum altitude at which each power rating can still be maintained is known as the critical altitude.

It's easier to maintain a lower power rating up high. That's why WEP has the lowest critical altitude, military power is next, and normal power the highest.

[GregP]

Buzz,

I was looking at your second set of performance numbers, near the bottom where it says "Service Ceiling." Service ceiling is not a critical altitude ... it is the altitude at which the rate of climb has fallen to 100 fpm ... at least in US military technospeak.

But ... yes, I am aware of power drop-off with altitude since I am a pilot.

I had always concentrated on the Corsair's earlier versions since they were the primary weapon, and had not realized that they had fitted a 2,800 hp engine to the airframe in the F4U-5.

It could also be true that improving the engine to 2800 hp also meant a slight improvement in the supercharger design, resulting in maintaining more power at higher altitudes, and THAT could acocunt for extra speed as easily as anything else.

Until now, I always considered the F4U-5 to be essentially a post-WWII airplane like several others that were good performers. Good piston fighters after WWII wereusually not produced since jets were the "new wave" of the future, though at laeast one more generation of prototypes were designed an built in case the jets experienced major teething problems. Some did.

The Swiss Doflug 3802/3803 come to mind. They were designed and built, but never bought since American P-51s were avilable at bargain prices in the post-WWII timeframe.

Anyway, thanks for bringing up the marked improvement of the F4U-4 and -5 over the F4U-1's performance numbers. I have never been a Corsair fan in particular, but am now much more interested in looking into it considering the performance improvements over older versions.

This makes me wonder what an F6F-7 Hellcat with 3000 hp might have been like!

[BuzzLightyear]

I was looking at your second set of performance numbers, near the bottom where it says "Service Ceiling." Service ceiling is not a critical altitude ... it is the altitude at which the rate of climb has fallen to 100 fpm ... at least in US military technospeak.
But ... yes, I am aware of power drop-off with altitude since I am a pilot.

OK, I thought you were looking at the critical altitudes. Sorry.





It could also be true that improving the engine to 2800 hp also meant a slight improvement in the supercharger design, resulting in maintaining more power at higher altitudes, and THAT could acocunt for extra speed as easily as anything else.

The F4U-5 had a completely different supercharger than did the F4U-4. The Supercharger on the F4U-4 was of essentially the same design as on the F4U-1. The F4U-5 was completely different.

The R-2800-32W engine utilized the integral main stage supercharger like earlier Corsair engines, but the auxillery stage utilized the so-called "Sidewider" blowers. This was a variable speed unit (as opposed to a 2 speed unit). It used 2 impellors on a common shaft. Here is a picture of it:

http://members.cox.net/rowlandparks/32w.jpg

BTW, that blower you see on the side - there is another one just like it on the other side.

And no question about it, the F4U-5 WAS a post-war plane. I don't think it went into service until 1947. But it was a viable fighter even in 1950. The only non-jet ace in the Korean War flew a night-fighter version of the F4U-5.

[GregP]

Thanks for the photo, Buzz. 2800 hp from 2800 cubic inches is almost unheard of, so I hadn't really considered it. That output is similar to the output from the Wasp Major of 4360 cubic inches! WOW!

Bet the engine service life was short if you ran it at 2800 hp for any extended time though. Maybe not, but 1 hp per cubic inch is difficult even today in a piston engine ... unless you talk motorcycles.

Phenomenonal, and would definitely account for a hose-nose going 470 mph.

Usually I stick to metric units, but 1 hp per cubic inch is a noble goal to achieve and doesn't quite sound the same in metric units.