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).
Braking curves, comparing theoretical principles with published car performance data.
| Identifier | ExFiles\Box 73\3\ scan0283 | |
| Date | 19th March 1925 guessed | |
| contd :- -3- For the braking curves below 50 m.p.h., the time to pull up from any given speed is directly proportional to the speed. The distance to pull up however, is proportional to the square of the speed. Above 50 m.p.h. the curves are slightly modified by windage which then becomes appreciable. We have noticed a large number of curves of car performances which have been recently published in motor Journals. We are not impressed by these curves. Some of them do not even follow the physical laws to which they must inevitably be subjected. The reason for this may be that the method of conducting the test allows errors to creep in, or that the instrument upon which the results of the tests rely (in most case, the speedometer) from some fundamental characteristic of its own, has a direct bearing upon the results obtained. We have a number of these curves before us and will let you have an analysis of one or two shewing where they are incompatible with the results which should be obtained from cars as they are at present being sold to the public. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||