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).
Page 4 of an experimental report critiquing the braking test methodology used by 'The Motor' magazine.
Identifier | ExFiles\Box 32\2\ Scan066 | |
Date | 23th March 1925 | |
R.R. 493A (50m) (D.B. 175 25-9-24) J.H.D. EXPERIMENTAL REPORT. -4- Expl. No. REF:Hs{Lord Ernest Hives - Chair}/Rml/LG23. 3. 25. on dry concrete, we may take it that for pull ups from 40 m.p.h. and below the retardation should be uniform. Therefore for any given distance to rest there is a definite time which should be taken and can be easily calculated mathematically. It would appear that 'The Motor' representative is aware that the time to rest should be proportional to the speed from which the pull-up is made, and so he measures his distances and plots them out in a straight line against a time base as in Graph C. or a gentle curve as in 'A'. Actually from the distances which are given to bring the car to rest, the times taken should correspond to the dotted lines we have inserted, which give a more accurate idea of the uneven nature of the results obtained. We have endeavoured to indicate that 'The Motor' tests are not a really accurate indication of a cars' braking capabilities by selecting these few tests for criticism. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||