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).
Proposed wind tunnel experiments on streamlined car bodies to reduce windage for high-speed motoring.
| Identifier | ExFiles\Box 12\6\ 06-page059 | |
| Date | 4th August 1931 | |
| 87830 To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/Am. c. Sg.{Arthur F. Sidgreaves - MD} c. Wor.{Arthur Wormald - General Works Manager} Da.{Bernard Day - Chassis Design} c. E.{Mr Elliott - Chief Engineer} Ry. Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}2/AH 4.8.31. STREAM LINED BODIES - R.R. CARS. X5330 Recently, conditions of motoring have so altered that we believe it is now worth while our carrying out some experimental work on reducing the windage of car bodies. There are at present, arterial roads under construction which permit of speeds of 80 m.p.h. being indulged in without danger, and at the same time the silent 3rd with an easy change enables a high rear axle ratio to be used because the desired acceleration can be obtained on the silent 3rd speed. This means that 80 m.p.h. road speeds may be utilized without over-revving the engine. With a view to seeing what such experiments would cost and how they could be carried out, we visited Messrs. Vickers who have a wind tunnel and have carried out the majority of the experiments on stream-lining for such cars as Parry Thomas's Leyland, the Bluebird and the Golden Arrow etc. They stated that they liked to work on models about 2 feet long - this would be about 1/8 scale for our cars. They would prefer that the model did not weigh more than 5 lbs. From their point of view, the most economical procedure was to have a model with the features which it was proposed to alter made detachable with alternative shapes. They could then carry out a series of tests very quickly once the model was fixed up in the wind tunnel. A provisional estimate for the cost of wind tunnel work is £5 a day. If we do not ask them to do any work as regards plastercine or other alterations to the model, they say that in two days they would be able to cover a lot of ground. Obviously, it is desirable as far as possible not to depart from utilitarian alterations to the body which might reasonably be expected to be acceptable to the public. The features which we should consider might be susceptible to alteration are :- (1) The front and rear wings. (2) The running boards. (3) The back end of the car. (4) Windscreen and top thereof, angle of slope, vee etc. (5) The underside of the car generally. | ||