Spitfire Mk.XIV vs P-51D Mustang

[pbehn]

This is interesting about the Specifications possibly being adjusted to fit the prototype. Seems backwards

Actually happens often in oil field engineering. All specifications are written in cooperation with manufacturers, otherwise you specify what cannot be done, then you issue a new spec for what can be done, if you catch my drift.

 

[Glider]

Wasn't the Supermarine 300 submitted to the same specification? I may be wrong. My main point being that the Spitfire wasn't specifically built to be an interceptor.

The Spitfire and Hurricane were designed for speed and climb which in my view is the basis of an interceptor. Clearly the Spitfire was far ahead but remember that when the Hurricane first entered service, there was nothing anywhere to touch it.

 

[Clayton Magnet]

Also from wiki...
" On 3 January 1935, they formalised the contract with a new specification, F10/35, written around the aircraft. "

 

[Clayton Magnet]

The Spitfire and Hurricane were designed for speed and climb which in my view is the basis of an interceptor

It would be interesting to see if time to altitude requirements were incorporated into the specification.
Anyway, would you still consider the Hurricane to be an interceptor? Certainly not by 1942, but again, I may be wrong.
As far as I remember, both aircraft (Hurricane and Spitfire) were designed to be fast monoplanes, with retractable gear, and able to destroy an enemy aircraft in one pass.
EDIT:
With eight .303 Brownings being almost unheard of firepower in 1935

 

[Shortround6]

Maybe not initially, but that's what it was developed into, the Mustang was never developed into that role...

Ah, did it need to be?
P-51Bs without drop tanks could go from sea level to 20,000ft in under 7 minutes (one test 5.9 minutes) which if not quite as fast as a contemporary Spitfire is several minutes faster than the Spitfires of 1940.
How fast did a 1943 "interceptor" need to get to 20,000ft in given the improvement in radar warning in 1943 vs 1940?

If, in 1943, the difference between on fighter making it to 20,000ft 5 minutes and another making it 6 minutes actually affected the success of the intercept then something was wrong with radar warning or the vectoring from fighter control.

 

[Glider]

It would be interesting to see if time to altitude requirements were incorporated into the specification.
Anyway, would you still consider the Hurricane to be an interceptor? Certainly not by 1942, but again, I may be wrong.
As far as I remember, both aircraft (Hurricane and Spitfire) were designed to be fast monoplanes, with retractable gear, and able to destroy an enemy aircraft in one pass.
EDIT:
With eight .303 Brownings being almost unheard of firepower in 1935

The specs for the Hurricane and Spit were designed around the aircraft. Re the question on the Hurricane remember we were discussing the design and I have no doubt that both were designed as interceptors.
A personal view is that the Hurricanes time as an effective interceptor was mid / late 1940, by 1942 it was well past its best when compared to other nations, but when it entered service, it didn't have to apologise to anyone. It just shows how technology was speeding up.

My brother often points out that Gloster went from the Gladiator to the Meteor. They did other designs in betwee,n but none that I can think of entered serious production.

 

[Shortround6]

The specs for the Hurricane and Spit were designed around the aircraft. Re the question on the Hurricane remember we were discussing the design and I have no doubt that both were designed as interceptors.
A personal view is that the Hurricanes time as an effective interceptor was mid / late 1940, by 1942 it was well past its best when compared to other nations, but when it entered service, it didn't have to apologise to anyone. It just shows how technology was speeding up.

My brother often points out that Gloster went from the Gladiator to the Meteor. They did other designs in betwee,n but none that I can think of entered serious production.

By the fall of 1940 the Hurricane was in trouble and they knew it, which is why the Hurricane got the Merlin XX engine. It was an attempt to keep the Hurricane competitive while newer fighters (Typhoon?) were built. Since the Spitfire was faster and climbed better it could make do with a 2nd best engine a bit longer.
The plan went to pot when the Germans didn't just stick a more powerful engine in the 109E but developed the F with much lower drag and then the Germans frosted the cake with the FW 190. The Hurricane, useful as it was in other roles or other theaters was toast as an interceptor/air superiority fighter over NW Europe by the end of 1941.

 

[pbehn]

My brother often points out that Gloster went from the Gladiator to the Meteor. They did other designs in betwee,n but none that I can think of entered serious production.

From 1934 Gloster was part of Hawker Aviation They produced Hurricanes and Typhoons as a sub contractor and developed the Gloster "Whittle" and Meteor Jets.

 

[CORSNING]

It would be interesting to see if time to altitude requirements were incorporated into the specification.
Anyway, would you still consider the Hurricane to be an interceptor? Certainly not by 1942, but again, I may be wrong.
The Hawker Hurricane Mk.I in early 1940 using 100 octane fuel and engine
boost of +12 lb. was calculated at an initial climb of 3,445 fpm. at a combat
weight of 6,750 lb. take-off. I would say that made it a decent interceptor
in 1940.
The Hurricane Mk.IIA was capable of 2,710 fpm./S.L. at 7,397 lb. (+9.8 lb.).
It was cleared for +12 lb.

 

[CORSNING]

Ah, did it need to be?
P-51Bs without drop tanks could go from sea level to 20,000ft in under 7 minutes (one test 5.9 minutes) which if not quite as fast as a contemporary Spitfire is several minutes faster than the Spitfires of 1940.
How fast did a 1943 "interceptor" need to get to 20,000ft in given the improvement in radar warning in 1943 vs 1940?

Shortround, I will never grow tired of reading your posts sir. They
are always very interesting.
Since Warbirds forum closed down, I had to do some serious digging
to find the information I needed to complement your post.
My personal opinion is the Spitfire Mk.XIV was the best all round high
altitude and possibly medium altitude interceptor of WW2. The following
information is purely just to show the skeptics just how close the Merlin
powered Mustang actually compared to Great Britain's aircraft that set the
standard.
Spitfire Mk.XIV prototype on 27 October 1944 report using +18.3 lb. of
boost and weighing 8,400 lb. was capable of a maximum climb rate of
5,110 fpm and reached 20,000 ft. in 5.1 minutes. THE STANDARD.
The production Mk.14 using +18 lb. had an initial climb of 4,700 fpm.
This was calculated to increased to 5,080 fpm. using +21 lb. boost.
The following information comes from Mike Williams and Neil Stirling's
exceptional site wwiiaircraftperformance.org
P-51B-1 (8,430 lb.): 3 June 1943, V-1650-3/60.5" (+15 lb.), 20,000 ft./5.9 min.
P-51B-5 (9,205 lb.): 20 May 1944, V-1650-3/67" (+18 lb.), 20,000 ft./6.22 min.
Mustang III (9,200 lb.): 25 June 1944, -3/60.8" (+15.5 lb.), 20,000 ft./6.1 min.
P-51B-15 (9,335 lb.): 20 May 1944, V-1650-7/67", 20,000 ft./6.0 min.
P-51B-15 (9,335 lb.): 20 May 1944, V-1650-7/75" (+22.5 lb.), 20,000 ft./5.3 min.
Merlin III (9,260 lb.): Feb-May 1944, Merlin 100/80.9" (+25), 20,000 ft./5.25 min.
P-51D-15 fully loaded and all pylons using 9,760 lb./67", 20,000 ft./6.6 minutes.
No, the Mustang was not designed to be a high altitude interceptor...But,
should we now start comparing ranges for the two? How about level
speeds at sea level, 5,000 ft., 10,000 ft. or maybe 15,000 ft.?

 

[Clayton Magnet]

Are there any reports on the climb rates with the Griffon 65 boosted to 21 or 25"?
EDIT:
I mean PSI, not in/Hg

 

[CORSNING]

This doesn't really count because we are not talking about
the P-51H. Which from what I have read actually flew a few
sorties during WW2, no actual firing its guns though.
Sandard Aircraft Characteristics 22 March 1949.
Interceptor Mode (8,740 lb.): 473 mph./22,700 ft.
Initial rate of climb: 5,480 fpm.
At 9,585 lb. climb to 25,000 ft./6.7 minutes.
At 8,740 lb.: ?, Jeff

 

[CORSNING]

This graph has been graciously given to the public by Mr. Mike Williams.

Clayton, I have not seen any climb graph of the Spit 14 being tested at +21 lb.
The Spitfire MK.XIV was never cleared for +25 lb. boost.

 

[Clayton Magnet]

fair enough, thank you. I asked because of this chart, but perhaps the 25psi boost is a typo for the Mk.XIV?

 

[Vincenzo]

This is the famous K-4 climb curve with Gondalas?

talking of Corsning post

 

[CORSNING]

Clayton,
No sir, it is not a typo. The Griffon 65 was tested at +25 lb.
It just was never cleared for combat at that level of boost.
It was an engine failure vs.performance gain kind of thing.

I can tell you this. If Mr. Edgar Brooks was still here, that
good old boy could have explained the reasons why way
better than I will ever be able to.

 

[CORSNING]

This is the famous K-4 climb curve with Gondalas?

talking of Corsning post

WHAT?

 

[Vincenzo]

WHAT?

Kurfürst - Articles - Notes for "Spitfire Mk XIV versus Me 109 G/K A Performance Comparison"

 

[CORSNING]

Wing gondalas: Bf.109K-6

 

[Glider]

a blast from the past