Fw-190 vs Spit/P-51/P-47

[drgondog]

First when comparing these aircraft you need to look at their actual roles! I have the unique insight from two of my Uncles who each flew Spits and Mustangs... The P-51 D was designed to escort long range bombers and gave up performance in order to be more heavily built.

The P-51 was first and foremost designed and built to be a better fighter than the P-40, by NAA which proposed such to the Brits in April 1940. The 'keys' to the P-51 were a.) exceptional airframe with the best (lowest) drag of all WWII fighters except the P-80 and b.) enormous (for that time) fuel capacity. The original Allison engine was a no-go for 'long range bomber escort' for the US because escort altitudes were 10,000 feet above the Allison Critical Altitude.

The Spit and most other fighter/interceptors of WWII were built to dogfight and intercept other aircraft... In most cases the American Aircraft were underpowered at first and had more stringent building requirements which is why they were heavier... The P-51D did its job better than any other aircraft; And so did the spitfire! The later variants of the Spitfire, XIV etc. all had more powerful Griffon and Merlin engines in them. So, in combination with the lighter weight its no wonder it outperformed the "D".. However, if you look at the final Variant of the P-51, P-51G/H which was designed more as a fighter/interceptor where they shaved of weight and added the more powerful Merlin and Griffon engines the P-51 performance now tops all the other Spits and I believe all other prop fighters in top speed and rate of climb...

The entire P-51 line evolved as the missions dictated. Primary evolution was the Packard Merlin 1650-3 and -7 which extended top performance into the 20000 to 35000 feet of altitude realm mating the exceptional aerodynamics with a high altitude engines, adding wing rack and fuel capability to external tanks, and later adding an internal fuselage fuel tank to extend cruise range another 450 miles.

The P-51D MAX rate of climb was approx. 3,600 ft/ min, Spitfire Mk 21 4,800 ft/min, the MK XIV 5,000 ft/min, and the P-51G/H 5,200 ft/min
Top speed for the P-51G 495 mph, H 487 mph, Mk 21 455 mph, Mk XIV 443 mph, P-51D 437 mph...

They were both great aircraft and we were lucky they were fighting on the same side... In conclusion I would think PILOT ability and experience would win the day...

The dominant weight growth stages occurred when the Packard Rolls added 300 pounds in plumbing and engine over the Allison (P-51A to P-51B), then another 300 pounds for two extra 50 cal plus ammo (P-51B to P-51D).

In summary - the superiority of the aerodynamics coupled with internal fuel capacity is what separated the Mustang from the other ships named in this thread - the engine change enabled it to fulfill its potential.

The 600 pound decrease in weight of the P-51H from the D along with the 1650-9 engine made it very competitive with the Spit in all areas and superior to the FW 190D and all FW 190 subsets... plus parity more or less depending on altitude with the Ta 152.

 

[grampi]

Hi Everyone,

Soren requested I join this thread.



Do you have documentation showing this blanket de-rating of the BMW801? I certainly do not. However I have a numerous Beanstandungen's which show both JG2 and JG26 operating "de-rated" motors right alongside "normal" motors in June 1942. This makes sense as neither BMW or Focke Wulf list any other settings beside the "normal" ratings.

De-rating is tool to manage engines serviceability. All air forces operate "de-rated" motors. The most common reason for "de-rating" an engine is to burn stocks of inferior grade aviation fuel. All engines are "de-rated" for a period of time when they are brand new. It is called the break in period. BMW801's were de-rated for their first 10 hours of operation. The "de-rating" consists of pre-threaded holes in the throttle mount in which a screw is placed limiting the advance of the throttle. To return the engine to "normal" you remove the screw.

Here is an excerpt from an upcoming magazine article I am writing:



Motors that were modified were not restricted to overland flights.

This exactly what the FW190A1 Flugzeug-Handbuch instructs for the overhaul instructions for the BMW801C2 motor:



Teilüberholung instuctions can be found in the BMW Flugmotoren BMW801 MA, ML, C, u. D Handbuch und Teilüberholungsanleitung.

All new designs experience some teething troubles. I fear if WWII had started in 1937, the R-2800 would have the reputation as being very unreliable alongside the BMW801!



http://www.enginehistory.org/NoShortDays/Development of the R-2800 Crankshaft.pdf

I loathe getting into a performance comparison discussion. They are in fact very silly undertakings given the facts of the science behind aircraft. All aircraft performance comes from the manufacturer not as absolute performance but rather as a mean average over a guaranteed performance range. Additionally atmosphere was not standard during WWII and testing procedures certainly were not either.

In the case of WNr. 313, the performance as tested by the RAE appears to be pessimistic but not outside the realm of possibility. The climb testing was calculated off four datum points gather from partial "saw" climbs at 3500 feet and 17,000 feet. Rough running of the motor was experienced throughout the test and caused one datum point to be completely disregarded by the engineers. The Tactical Trials of WNr. 313 as tested several days later were cut short due to the rough running of the engine. The RAE then removed the motor and bench tested it to determine mixture settings and timing information. Mixture/Timing adjustments and spark plug change allowed that particular motor to run smoothly on the bench. It was never flight tested and in June 1942 the alkane ratio of C3 fuel was adjusted. This prompted new plugs for the motor and a change in the mixture and timing regulations.

Here is Focke Wulf tolerances:

Here is an RAF memo explaining aircraft performance variation:

Here is the order I would rate these fighters:

#1 FW190 if I was Luftwaffe pilot who flew the FW190.

#1 Spitfire if I was an RAF pilot who flew the Spitfire.

#1 P51 if I was a USAAF pilot who flew the P51.

All the best,

Crumpp

Chuck Yeager has stated many times that he would take the P-51 over any other prop fighter...that doesn't mean it's the better plane, just means he prefers it over the others...this goes right in line with your rankings...

 

[grampi]

The dominant weight growth stages occurred when the Packard Rolls added 300 pounds in plumbing and engine over the Allison (P-51A to P-51B), then another 300 pounds for two extra 50 cal plus ammo (P-51B to P-51D).

In summary - the superiority of the aerodynamics coupled with internal fuel capacity is what separated the Mustang from the other ships named in this thread - the engine change enabled it to fulfill its potential.

The 600 pound decrease in weight of the P-51H from the D along with the 1650-9 engine made it very competitive with the Spit in all areas and superior to the FW 190D and all FW 190 subsets... plus parity more or less depending on altitude with the Ta 152.

Most people conveniently forget about the "H" model when getting into these comparison discussions...it would have given even the Bearcat fits...

 

[DerAdlerIstGelandet]

Chuck Yeager has stated many times that he would take the P-51 over any other prop fighter...that doesn't mean it's the better plane, just means he prefers it over the others...this goes right in line with your rankings...

He won't be responding. He has not been a member here for quite some time.

 

[grampi]

He won't be responding. He has not been a member here for quite some time.

I wasn't expecting him to respond...

 

[tomo pauk]

The Fw 190 posessed some distinctive qualities vs. other top fighter of the war, in some features was at least equal, and in some features lagged when Allied designs received improvements. The rate of roll was superb, firepower was heavy for the era, speed and RoC were excellent until Allies deployed 2-stage engined fighters. Visibility was very good, the Kimmandogeraet eased pilot's work load. Nobody regarded the Fw 190 as flimsy, or badly protected (though the protection was over-done with later marks).
Shortcomings were, before late 1942, mostly connected with the engine and it's installation, the reliability was low until refinements in the engine & installation were worked out. The engine istallation have had the flaw in being too squished; the external intake was an afterthought that gave better hi-alt capability, but also a bigger drag (not much of concern in climb).
Where the Fw 190A could not compete vs. later Allied fighters was at altitude above 20000 ft, the single stage supercharger has it's limits. Steve/Stona has kindly provided translations of German radio trafic where Fw 190 drivers prefer to stay clear from 4-mots whenever P-47 is spotted nearby.
Fw 190D upped the performance figures, not just via the small increase in power, but also via reduction of drag, while also using the external ram air intake. Problem with 190D is that it came almost a year after it was feasible, ie. too late to matter.
It did not featured that great combat range/radius, a major shortcoming. As fighter-bombers, I'd rate them higher than P-51 or Spitfire, and equal to P-47. Fw 190A could carry a torpedo, that's not too shabby either.

The Germans dropped the ball with a too late introduction of Fw 190 with a 'big' V-12, whether from Jumo 213 or DB 603 line, or both.

 

[FLYBOYJ]

Chuck Yeager has stated many times that he would take the P-51 over any other prop fighter...that doesn't mean it's the better plane, just means he prefers it over the others...this goes right in line with your rankings...

he also said the P-39 was one of his favorite aircraft to fly...

 

[GrauGeist]

The P-39 was also one of Aleksandr Pokryshkin's favorite aircraft, too.