Spitfire Mk. V Performance Testing

Aeroplane and Armament Experimental Establishment
Boscombe Down

29 April 1941

Spitfire Mk. VA X.4922
(Merlin XLV)
Brief Performance Trials

SUMMARY

Results of tests.

.......(a) The top speed of the aeroplane is 375 m.p.h. at 20,800 feet.

.......(b) The maximum rate of climb is 3,140 feet per minute at 14,400 feet. The time to 20,000 feet is 7.1 minutes and the Service ceiling is 37,700 feet.

.......(c) The radiator is not quite suitable for English summer conditions on the climb.

.......(d) The oil cooler is suitable for English summer conditions on the climb.

.......(e) The take-off run in zero wind and standard conditions is 330 yards, and the distance to clear a 50 foot screen is 530 yards.

.......(f) The airscrew setting of 34 deg. to 54 deg. is suitable for the aeroplane under all conditions of flight.

For the full report see X.4922 Report


Aeroplane and Armament Experimental Establishment
Boscombe Down

18 June 1941

Spitfire Mk. VB W.3134
(Merlin 45)
Brief Performance Trials

SUMMARY

.......Brief performance trials were required of a Spitfire Mk VB fully operationally equipped for comparison with two other aircraft of the type not operationally equipped and previously tested at this establishment.

Height
feet
Top
Speed
M.P.H.
Time to Climb mins.Rate of
Climb
Ft/min.
S.L..0.
2,000.0.63240
5,000.1.53240
10,0003313.13250
15,0003514.63250
20,0003716.42440
25,000359..
30,000.12.21170

For the full report see W.3134 Report


Aeroplane and Armament Experimental Establishment
Boscombe Down

8 March 1942

Spitfire Mk. Vc AA.873
(Merlin 45)
Brief Performance and Handling Trials with
4 - 20 m/m guns fitted
.

SUMMARY

Results of tests.

.......(i) The maximum rate of climb is 2,900 feet/minute at 13,400 feet. The time to 20,000 feet is 7.4 minutes, and the estimated service ceiling is 36,400 feet.

.......(ii) The top speed is 374 m.p.h. at 19,000 feet.

.......(iii) There is no noticeable difference between the handling characteristics of this aeroplane and other Spitfire V types.

For the full report see AA.873 Report


Aeroplane and Armament Experimental Establishment
Boscombe Down

15 April 1942

Spitfire Mk. VB (Tropical) AB.320
(Merlin 45)
Position error, and performance with and without
a 90 gallon external overload tank

SUMMARY

.......This report deals with performance trials on a fully tropicalised Spitfire V.b. with a Merlin 45 engine, with and without a 90 gallon external fuel tank. The performance results were as follows:-

Without tankWith tank
Weight6695 lb7485 lb
Maximum rate of climb2660 ft/min.2145 ft/min.
at full throttle height of14,000 ft.14,000 ft.
Service ceiling36,30034,500 ft.
Time to 20,000 feet8.0 mins.10.0 mins.
Maximum speed354 m.p.h.337 1/2 m.p.h.
at full throttle height of17,400 ft.17,400 ft.

For the full report see AB.320 Report


Aeroplane and Armament Experimental Establishment
Boscombe Down

25 November 1942

Spitfire Mk. VC AA.878
(Merlin 45)
Climb, speed, and cooling tests at combat rating

SUMMARY

.......The operational limitations of the Merlin 45 have been increased, the use of 3000 R.P.M. and +16 lb/sq.in. boost being now permitted for periods not exceeding 3 minutes during combat. Tests have been made to determine the performance of the aeroplane at this new rating, and also whether the oil and radiator cooling are adequate.

.......(a) Climb performance.

Combat ratingNormal rating
Maximum rate of climb (ft/min)3710 at 8,800 ft.2650 at 14,900 ft.
Time to 10,000 ft. (minutes)2.73.8
Time to 20,000 ft. (minutes)6.157.9

.......(b) Level speed.
Maximum level true airspeed (m.p.h.)369 at 13,000 ft.359 at 19,900 ft.

.......The results show that the rate of climb is increased by about 1,100 ft/min. below 8,800 ft. by the use of combat rating. Above this height the increase is less, falling to 300 ft/min. at 15,000 ft.

.......In level flight the maximum level true airspeed is higher by about 35 m.p.h. below 13,000 ft.; above this height the increase in speed is less and falls to zero at 19,900 ft., the full throttle height at normal rating.

For the full report see AA.878 Report


Aeroplane and Armament Experimental Establishment
Boscombe Down

2 January 1943

Spitfire (F) Mk. VB W.3322
(Merlin 46)
Performance trials with Rolls-Royce S.U.
fuel injection pump

SUMMARY

.......A Rolls-Royce S.U. fuel pump has been fitted to Spitfire (F) Mk.VB, W.3322 in place of the normal A.V.T.40 float type carburettor and the performance of the aircraft has been measured as part of a general schedule of tests including fuel consumption, carburation and behaviour under negative "g".

.......The principle results at a weight of 6,516 lb. are:-

ClimbMaximum rate of climb (2850 r.p.m.)2,740 ft/min.
Service ceiling (100 ft/min)39,400 ft.
Time to 39,000 ft.27 3/4 min.

Level SpeedsMaximum speed - 368 m.p.h. at 22,500 ft.

.......The aircraft is appreciably better than most other Spitfires, after allowing for differences in weight and wing span, the gain being about 1,500 ft. in ceiling and 8-10 m.p.h. in top speed. Both of these improvements may be attributed to the removal of the carburettor, causing a lower pressure drop of the engine air before entering the supercharger, and thus giving an appreciable rise in boost pressure.

For the full report see W.3322 Report


Aeroplane and Armament Experimental Establishment
Boscombe Down

25 May 1943

Spitfire F. Mk.VB W.3228
(Merlin 50 M)
Climb and level speed performance when fitted with a
Merlin 50 engine with a cropped supercharger impeller

SUMMARY

........Spitfire F. Mk.VB W.3228 has been fitted with a special Merlin 50 engine, on which the supercharger impellor was "cropped" to a diameter of 9.5". On this engine the maximum permitted boost at combat rating was +18 lb/sq.in. instead of +16 lb/sq.in. as on a normal Merlin 50 engine. Climb and level speed measurements have been made at this combat rating and form the subject of this report.

........(a) Climb.

Maximum rate of climb4270 ft/min. at 3850 ft.
Maximum rate of climb at 10,000 ft.3800 ft/min.
Maximum rate of climb at 20,000 ft.2320 ft/min.
Service ceiling35,700 ft.
Estimated absolute ceiling36,400 ft.

........(b) Level Speeds.

Max. level true airspeed at 2,000 ft.334 mph.
Max level true airspeed at 5,900 ft. (FTH)350 mph.
Max level true airspeed 10,000 ft.347 mph.
Max level true airspeed 20,000 ft.336 mph.

For the full report see W.3228 Report


Merlin 46 and 47 Power Chart
Operational Notes for Pilots on Merlin 46 Engines
Merlin engine ratings January 3, 1942
Spitfire V, Merlin 45, Performance Chart - RAE
Merlin XLV - Operational Limitations
Measurements of the Flying Qualities of a Supermarine Spitfire VA Airplane - NACA
Stalling Characteristics of the Supermarine Spitfire VA Airplane - NACA
Comparison of Spitfire V and Me 109 F1/2

WWII Aircraft Performance