From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Visit to Martlesham discussing high altitude carburation issues on supercharged engines.
| Identifier | ExFiles\Box 179\2\ img148 | |
| Date | 9th January 1932 | |
| ORIGINAL To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/Lov.{Mr Lovesey} c. Sg.{Arthur F. Sidgreaves - MD} Wor.{Arthur Wormald - General Works Manager} c. Rg.{Mr Rowledge} E.{Mr Elliott - Chief Engineer} c. By.{R.W. Bailey - Chief Engineer} EP.{G. Eric Platford - Chief Quality Engineer} c. Lr.{Mr Ellor} Lp.{Mr Lappin} Hs{Lord Ernest Hives - Chair}/Lov.{Mr Lovesey}3/KT.9.1.32. X1908. X3933. HIGH ALTITUDE CARBURATION ON SUPERCHARGED ENGINES - VISIT TO MARTLESHAM. On Thursday I visited Martlesham on the Fairey J.F. to show them the progress we were making in connection with the troubles they are experiencing in the operation of the supercharged Kestrels at high altitudes, and to see how a similar scheme to the one we have on the J.F. could be applied to the Hawker "Fury". The whole question of high altitude flying and the experience obtained on the supercharged Kestrels was discussed with Sq/Ldr. McKenna, F/Lt. Wincott - who is O/C. the Interceptor Flight - and F/Lt. Boothman. The problem is that in winter temperatures the full supercharged Kestrels, as used in these Interceptors, cannot be relied upon to operate satisfactorily above 20,000 ft altitude. It may occur at first thought that flying above 20,000 ft and at temps. as low as -40 to -50°C is unnecessary, but the Interceptor is the offensive arm against the long distance day bomber, and even as far back as the War, we conducted most of our long distance day bombing at 18,000 to 20,000 ft. It is therefore necessary for our Interceptor to operate satisfactorily up to about 30,000 ft. The highest they have been able to fly the Fury this winter is 28,500 ft (indicated) which with the various corrections is not much more than 26,000 ft actual, and on this occasion a temp of -52°C was recorded. This flight was made with extra water heating to the carburetter using separate pipes for the heating of the chokes and the diffusers. Even with this, the mixture control had to be full rich above 20,000 ft and several periods of partial "cutting out" occurred from 20,000 ft to the maximum altitude. The "cutting out" was coincident with petrol spray from some exhaust ports. Below 20,000 ft. they do not complain, but above this they have no control of the carburation. This point is important because at some time we probably hope to develop an automatic mixture control and such could not be possible unless operation of the mixture control obeys some fixed law with altitude. Therefore any device such as they have tested on the Fury of extra heat to the diffusers, which enabled them to obtain higher altitude, but only at the expense of running full rich, could hardly be used in combination with automatic carburation control. | ||