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

[davparlr]

T They weren't trying to make their aircraft 'look good', they were trying to find out the actual performance so as to either develop new models or develop tactics for existing models.

This is a very good point that needs to be reiterated. Flight test are rarely used to promote the performance of the aircraft and it is even more rare for a user force test to promote the performance. Most test are for the tasks identified by Shortround. Overstating an aircraft performance by the user force was very dangerous to the combat pilot, expecting more from the aircraft than it will provide. Knowing the limitations of one's aircraft is one of the vital requirements of successful air combat. It is, however, not unusual to find that the aircraft has been "cleaned up" by filling gaps, polishing and/or taping gun ports. This is probably done for several reasons, one of which is to provide max performance possible, another may be to minimize aircraft variables such as manufacturing tolerances. Most test reports identify the condition of the aircraft at the time of the test.

There may be some test that indeed are meant for the aircraft to "look good". These are usually limited to subcontractor test to sell the aircraft to the military or foreign governments, or for the military to get more funding from the government.

Several type of data sets are usually available on-line. One is manufacturers estimates of performance. These are usually based on aerodynamic calculations of aircraft performance and generally represent an optimized performance and should be taken as informational unless no other data is available. An example of this is found on this Mike Williams site.

http://www.wwiiaircraftperformance.org/mustang/na-46-130-chart.jpg

The most reliable data set is provide by calculated, or plotted, data verified by actual test points performed. This is a typical, and accepted by industry and military as a valid performance methodology. This can be quickly identified by in the inclusion of an identified aircraft tail number and test weight and often other data such as engine type, fuel type, etc. Also, it often identifies a test engineer. Below is an example of this type of data. Some data may look official but lack identification.
In this case, it should be examined in context, e.g., is it associated with a test report.

http://www.wwiiaircraftperformance.org/mustang/p51b-44-1-level.jpg

Mike Williams site is excellent for the data it provides.

 

[Altea]

Hello M jim

Mr Readie
1) The site you give about Spit IX and Bf 109G is not to be trusted (e.g notice when it says that 1,42 ata was cleared)

I don't understand what du you mean. Wasn't it cleared -or reduced, at leastst for quoted Bf-109 trials?

2)Merlin was a superb effort but you must remember a) in 1940 time combination merlin/spit was inferior to DB/Bf109 .

I don't know if M Williams site is biaised, or that biaised, it's far from being that* unsustainted. Why do you think the airframe/ engine combination was better for the Bf-109 in 1940?

* as your own post...

 

[Shortround6]

Yes, but I believe, after so long repeat, you should put something factual on the table (call it bogus facts) not just argue argue argue.. anyone can argue, in fact most people on internet just argue. But I learn from those who also put fact on table, like I did when you posted about engines now.

You ask and you shall receive. But then I have asked for figures or facts from you and gotten little but arguments. Not actual drag figures but vague comparisons to other aircraft.

You know engine very well, thanks for explanation, very useful. Also thank you for accepting my point. You know see why DB engine fuel effiency improved. So you also see why 109 range improved, with no need for heavier load of fuel.

Thank you for the compliment. I will not deny that DB engine fuel effiency improved, I just don't think it improved as much as you do. I know that is not a fact but I will return to this. Engines can show different 'efficiencies' and different speeds or power outputs. Since "there is no such thing as a free lunch", improvements have to paid for somehow. Like fuel injection, it is more efficient than carburetors but it is more costly and difficult to manufacture and maintain.

Yes, British used aftercooler device, but tell me, from where and what does after cooler cools, and how efficiently, compared to water that evaporate inside engine where heat is generated? Aftercooler cools charge in supercharger, not walls of engine.. anyway DB sheet says this data.

The after cooler cools in the intake charge, not the engine, you are quite correct in this. But consider this, intake heat goes right through the engine. By this I mean that if you increase the temperature of the air going into an engine by 100 degrees you will increase the peak temperature inside the cylinder by 100 degrees and the exhaust temperature by 100 degrees. R-R figured (measured) that the evaporation of the fuel in supercharger of the early Merlins lowered in the intake charge temperature by 25 degrees C. This is what some of the MW/50-ADI-water injection does for an engine. At any given pressure, the lower the temperature the denser the gas/air/intake charge. The denser the more power.
There is a limit for any given fuel on the amount of boost, cylinder compression ratio and intake charge temperature that can be used before detonation sets in. Change one factor and you can/have to change another. Every model of engine responds a bit differently so the limit on one model is not the limit on another. The Germans had no fuel evaporation in the supercharger except on a few select engines. Some of their engines in the 1400-1600hp category could pick up around 100hp by using water injection WITHOUT increasing boost just due to the lower charge temperature as could certain models of the JU 211 engine that used an after cooler on their single stage supercharger (I think the ONLY aircraft engine in WW II to use an aftercooler on a single stage supercharger?) The after cooler on the two stage Merlin allowed for a much lower intake temperature than would other wise be the case for an manifold pressure that high. This not only allowed for a higher boost level to be used but lowered (or traded) the thermal load. More fuel burned means more heat generated but if the air in the cylinder is lower in temperature to begin with the peak temperature in the cylinder may not be that much different. That is the theory anyway.
The DB engines used a low level of boost for most of the war and didn't need such tricks as after coolers and ADI until they went for the 1.8-1.98 AtA levels of boost. I notice that they didn't try to increase the RPM any more after the DB601E. Back to the " there is no such thing as a free lunch". The Merlin gained a little bit of weight in the block and other parts at time went on. It gained a lot of weight when it went to the two stage supercharger. The DB engine went from 590KG in the 601A-0 model to 745KG in the 605DC model. First 605 model went 720KG. The increased RPM and bore size were not "FREE". They cost over 100kg of engine weight or about 22%. Which is about the same (with in a couple of %) as the weight increase from a Merlin III to a Merlin 61 not including the intercooler radiator and fluid. But then the Merlin 61 could put out a lot more power than an early DB 605 couldn't it? And do it higher up.

Why are you returning again and again after shown data? Real data for range is at Micheal Rautsch page for F4. http://www.beim-zeugmeister.de/zeugmeister/index.php?id=22

410 km/h at 130 liter/h. Complete tankage 400 liter, 1260 km is possible, but of course its lot less with climbing etc. In cruise, 8.9 mpg is possible.

Ok, Lets look at that data.

Bf109F-4 at 1000meters

315kph/196mph for a fuel burn of 120liters/26.4imp gal, 101 miles per 100lbs of fuel
425kph/264mph for a fuel burn of 215liters/47.3imp gal, 76 miles per 100lbs of fuel

Spitfire MK V at 2000ft/606 meters
.
327.4kph/203mph for a fuel burn of 140.9liters/31imp gal, 89.8 miles per 100lbs of fuel
377.4kph/234mph for a fuel burn of 159liters/35imp gal, 91.7 miles per 100lbs of fuel
411.3kph/255mph for a fuel burn of 191liters/42imp gal, 83miles per 100lbs of fuel

Bf109F-4 at 3000meters

370kph/230mph for a fuel burn of 130liters/28.6imp gal, 109.7 miles per 100lbs of fuel.
465kph/289mph for a fuel burn of 210liters/46.2imp gal, 85.5 miles per 100lbs of fuel.

Spitfire MK V at 10,000ft/3048 meters.

362kph/225mph for a fuel burn of 132liters/29imp gal, 106.2 miles per 100lbs of fuel.
452kph/281mph for a fuel burn of 191liters/42imp gal, 91.5 miles per 100lbs of fuel.

Bf109F-4 at 5000 meters

400kph/248mph for a fuel burn of 145liters/31.9imp gal, 106.5 miles per 100lbs of fuel.
505kph/314mph for a fuel burn of 250liters/55imp gal,,, 78 miles per 100lbs of fuel.

Spitfire MK V at 20,000ft/6096 meters.

423kph/263mph for a fuel burn of 164liters/36imp gal, 100 miles per 100lbs of fuel.
483kph/300mph for a fuel burn of 209liters/46imp gal, 89.3 miles per 100lbs of fuel.

Bf109F-4 at 7000 meters

410kph/255mph for a fuel burn of 130liters/28.6imp gal, 121.6 miles per 100lbs of fuel.
510kph/317mph for a fuel burn of 210liters/46.2imp gal, 94 miles per 100lbs of fuel.

Bf109F-4 at 9000 meters

490kph/305mph for a fuel burn of 185liters/40.7imp gal, 102.7 miles per 100lbs of fuel.
540kph/336mph for a fuel burn of 220liters/48.4imp gal, 95.2 miles per 100lbs of fuel.

Spitfire MK V at 30,000ft/9144 meters.

455kph/283mph for a fuel burn of 186.4liters/41imp gal, 94.6 miles per 100lbs of fuel.
539kph/335mph for a fuel burn of 214liters/47imp gal, 97.6 miles per 100lbs of fuel.

You know, I am just not seeing the huge advantage of the 109 here. Sometimes it is better and sometimes it is not. On average I guess it is better but we are talking an advantage in the single digits and low single digits at that most of the time.

Where is the extra drag of that 1930s airframe? where is the low efficiency of the Rolls-Royce engine?


Your arguments about the increased armament of the Soviet fighters are hollow. Replacing one 42kg gun and two 25kg guns with three newer 25kg guns may be more effective but it certainly doesn't increase the weight of the installed armament does it? Some LA-7s received three 25kg guns instead of the older two 42KG guns. More effective but the weight of the installed armament posed no penalty to the aircraft did it? Apparently the room was there for three guns, why didn't the Soviets install a third 42kg gun if adding weight of guns doesn't affect performance?

Entire history of WW II Soviet fighters was a search for more firepower balanced against what weight the planes could carry without loosing too much performance.

 

[tomo pauk]

Tiny questions: when was the 109F-4 1st used in combat, and in what time frame it was produced? Thanks in advance?

 

[Shortround6]

One book says it reached the front lines in June of 1941, about 1840 (?) produced. First "G"s show up in June of 1942. How long it took to replace the "F" of for the "F" to fade from service?????

 

[Milosh]

Tiny questions: when was the 109F-4 1st used in combat, and in what time frame it was produced? Thanks in advance?

As Shortround said. One of the first losses was WNr7020 piloted by Oblt. Lossnitz of 8./JG52 on July 1 1941 when it truck the ground, killing the pilot.

WNr 6999-7660 5.41-12.41 WNF
WNr 13001-13391 12.41-4.42 WNF
WNr 8267-8399 6.41-8.41 Erla
WNr 8400-8806 8.41-12.41 Erla
WNr 10001-10290 1.42-5.42 Erla

for operations see The Luftwaffe, 1933-45

from the Prien/Rodieke 109 book

 

[tomo pauk]

Thanks, people

 

[CORSNING]

davparir,
I read this thread and saw your post #221. You posted figures for the F4U-4, Fw-190D-9 and Spitfire XIV that show the F4U-4 at a disadvantage to the Fw-190D-9 at lower levels. My sources show this is not so.
An official document in Dietmar Harmann's book show that the 190D-9 performance was 380mph/S.L at W.E.P and Max Climb of 3,641fpm at military power. I think 4,430fpm at W.E.P. is very believable. Spitfire XIV at sea level you listed at 389mph and 5,000fpm. However these figures for the Spitfire were reached at +25 lbs. boost. I have read that it is not known if +25 was used in actual combat during WW2. At +21 the Spitfire reached 366mph at S.L. Climb rate for the Spitfire 14 at +18 was 4,700fpm. I haven't seen any document at this time for +21 boost. Please post if you have one. The military document I have on the F4U-4 give S.L. figures as 383mph and 4,770fpm. Your statement "Very late in the war when the F4U-4 appeared, it was slightly inferior to the Fw-190D-9 at lower altitudes" doesn't seem right. I am not an authority on German fighters so please let me know where your figures came from on the Fw-190D-9. It would be much appreciated. Thanks in advance, Jeff.

 

[CORSNING]

The Corsair held an edge in speed to both the Spitfire and 190D-9 up to 24,000ft. It definitely held a brute power advantage (2,760hp.WEP). It had no problem out climbing or climbing with either to that altitude (20,000ft/4,9min.) It could carry more than twice the load of the others. Ruggedness, no contest. All off the deck of a carrier if needed. That about puts it in the same league (at least or better).

 

[Vincenzo]

here F4U Performance Trials i can see, at best
F4U-4 speed a s.l. wep 328 knt (378 mph) climb s.l wep 4360 fpm
And the F4U-4 is the younger of the group

edit 2760 hp i think it's too high

 

[CORSNING]

Vincenzo,
The R-2800-18W was rated at 2,450hp.W.E.P. and the later R-2800-42W was rated at 2,760hp.W.E.P. I haven't found any documents that say when the -42W began to be installed. For the performance figures I quoted, go to the sight you listed above and scroll to the bottom. Click on F4U-4 PERFORMANCE SUMMERY. In the foot notes (on page 3, I think) it gives maximum speeds in CLEAN CONDITION without pylons. If your going to compare two interceptors against the F4U-4 you have to deck the Corsair out in the same mode. Notice the performance figures are with the R-2800-18W engine.

 

[Vincenzo]

R-2800-42W was commonly reported installed from august 1946.
ty for the indications
strange that the actual test show lowest performances

 

[NeilStirling]

F4U-4B Bu No. 97486 onwards, constructed after 16th August 1946 were built with the R-2800-42W as standard. Vought F4U Corsair, page 116, by Martin W Bowman.

 

[CORSNING]

Thanks Neil and Vincenzo.

 

[davparlr]

davparir,

An official document in Dietmar Harmann's book show that the 190D-9 performance was 380mph/S.L at W.E.P and Max Climb of 3,641fpm at military power. I think 4,430fpm at W.E.P. is very believable.

This is close to the data I have

Spitfire XIV at sea level you listed at 389mph and 5,000fpm. However these figures for the Spitfire were reached at +25 lbs. boost. I have read that it is not known if +25 was used in actual combat during WW2. At +21 the Spitfire reached 366mph at S.L. Climb rate for the Spitfire 14 at +18 was 4,700fpm. I haven't seen any document at this time for +21 boost. Please post if you have one.

The Spitfireperformance site
150 Grade Fuel
does state at the bottom,

100/150 grade fuel was introduced into Spitfires of 83 and 84 Groups during January 1945: 43

And also implies 25 lb boost was approved for the XIV.

The military document I have on the F4U-4 give S.L. figures as 383mph

Most Navy tests I have seen has the SL speed at 375 mph but this is well within error.

and 4,770fpm.

This is where the data gets interesting. "America's Hundred Thousand", an excellent book on American fighters, shows SL rate of climb of 3700 ft/min at combat power, this is suspect. One official looking source, which you may be using, shows a ROC of 4800 ft/min. This also looks suspect to me, and is confusing. Several flight test shows the F4U-4, at Mil settings, has a rate of climb of about 3700 ft/min, which would explain the error in AHT. AHT shows max hp of the F4U-4 as 2380, or about 300 hp over Mil. This is similar to the P-47D increase from Mil to WEP. Calculating increase in ROC with 300 hp and comparing a similar increase in P-47 power implies a ROC of the F4U-4 at around 4300 ft/min at SL. This is also compatible with the F4U-4 Specification requirements.

http://www.wwiiaircraftperformance.org/f4u/80765-climb.jpg

The Corsair held an edge in speed to both the Spitfire and 190D-9 up to 24,000ft. It definitely held a brute power advantage (2,760hp.WEP)

I think you got the hp rating mixed up with the F4U-5. I could not find any reference that shows the hp of the F4U-4 higher than 2380 (AHT)-2450 (Great Book of WW2 Airplanes).

Now, based on the above information, and calculating F4U-4 ROC based on 4300 ft/min at SL, I have the following performances showing airspeed and ROC at altitudes. I threw in the P-51B (with post May '44 performance, no racks) just for perspective.

SL
F4U-4 375 mph 4300 ft/min
Fw-190D-9 385 mph 4429 ft/m in
Spit XIV 377 mph 5090 ft/min
P-51B 386 mph 4430 ft/min

5k
F4U 394 3700
D-9 405 4134
XIV 395 5000
P-51 400 4420

10k
F4U 417 3600
D-9 428 4134
XIV 414 4450
P-51 420 3900

20k
F4U 451 3300
D-9 423 2902
XIV 433 4000
P-51 442 3200

It is obvious that all four aircraft are comparable at these altitudes, with varying advantages, especially for the XIV in climb (climb data for the XIV specifically from interpretation from Mike Williams site and appear reasonable). However there is a time line issue in that the P-51B and XIV were contemporaries (late '43), the D-9 didn't show up till Fall, '44, and the F4U-4 didn't become operational until about VE day, mid '45.

 

[drgondog]

The M was slightly faster than the M, but was only made in a handful of numbers and didn't make it into service before the end of the European war.
Wonder how fast that went at 39,000ft

Wuzak - the 56th FG flew M's starting in December (with ignition harness issues) and lost their first P-47M-1 in combat on February 4, 1945.

 

[Vincenzo]

davparl i don't think that 25 lbs boos was available fo Spit XIV, almost not in time for effective use in Europe,
in this http://www.spitfireperformance.com/125wing-replacement-aircraft.jpg the 15th march '45 was delivered Spit XIVE with a interim version on 21 lbs boost

 

[davparlr]

davparl i don't think that 25 lbs boos was available fo Spit XIV, almost not in time for effective use in Europe,
in this http://www.spitfireperformance.com/125wing-replacement-aircraft.jpg the 15th march '45 was delivered Spit XIVE with a interim version on 21 lbs boost

I think that most of the data I used was at 21 lbs.

 

[davparlr]

Wonder how fast that went at 39,000ft

The P-47M speed at 39k was about 468 mph.

 

[joedee]

I hope this part of the thread is read again, because I read the account you mention in a library book a long time ago. I can not remember the P-38 pilot's name and I hope someone could tell me his name or even the name of the the book I read the account in. The book was about WWII fighters pilots. In the account you describe, the dog fight ended when the (38 ) finally was able to damage Galland's engine. Fate was on Galland's side because he was able to slip into a cloud bank nearby, and if I remember correctly he was able to land or crash land at an air field nearby. You know sometimes it comes down to one nationality claiming their greatest fighter was the best, even never outclassed, etc, but I believe these great designs, especially the later models whether English, American, German, or Russian were close enough in performance that it was ultimately the skill of the pilot in how he started the fight, or how well he was able to use the positive characteristics of his weapon against his enemy. The P-38 in Europe was not a complete success. It was only when Lockheed finally got it right in the (L) model did they really have a weapon as good as anything flying, but it took someone who was really good to get the most out of it, but then that's the way it is with flying any high performance aircraft. When they finally got the right (38 ) in Europe, the USAAF reduced its escort role greatly. Lockheed should have resolved the Aerodynamic and intercooler problems long before they did. In reality, I believe, in defence of Lockheed the Compressibility/maneuvering flaps units that helped prevent the (38 ) compressibility dive problems were lost when a troop ship they were on that was headed for a Mediterranean P-38 group was sunk by a German TV guided rocket launched by an ME-110. This lost in itself cost about another (6) months in getting them retro fitted on existing models. Yes the P-38 was a climbing fool and had very quick accelleration in comparison to the other top US fighters. In addition, nothing could match it in a zoom climb. In it's later version(J &H) it was a match for anything in capable hands- "Ask Galland". To say it was the best of the best- never get that from me. You guys with more know than I can throw mph, roll-rates, fpm, dive speed, turn rates, accell., etc at each other till dooms day and there won't be a definitive winner.
Joedee