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).
Calculation of the theoretical cornering speeds for a touring car and a bodied car before turning over.
| Identifier | ExFiles\Box 41\3\ Scan336 | |
| Date | 21th June 1923 guessed | |
| To estimate the theoretical speeds at which a touring car and bodied car with centre of gravities as found could negotiate a corner of 100 ft. radius if their springs were chocked up. This is assuming that they turn over about their outside track before skidding - (in point of fact, in this case they would skid first). m = wt. of car (lbs.) v = velocity of car (f.p.s.) r = radius of corner (ft.) x = ht. of centre of gravity (ins.) y = half track (ins.) g = 32 f.p.s² The car will turn over when the moment of the centrifugal force about its outside track just becomes greater than the moment of its weight about the outside track. or when x m v² / r g becomes m y or v² becomes v r g / x or v becomes √(y r g / x) Touring car y = 27 x = 24 r = 100 ∴ v (greatest speed) = √( (27 X 32 X 100) / 24 ) = √3600 60 f.p.s. or 40.9 m.p.h. Bodied car. y = 27 x = 28 r = 100 v (greatest speed) = √( (27 X 32 X 100) / 28 ) = √3080 55.5 f.p.s. or 37.8 m.p.h. It will thus be seen that it requires a large amount of top heaviness to make a material difference in cornering as regards actual turning over of the car. Our figures show a bodied car would only have to be 3 m.p.h. slower than a touring car to be safe round a corner of 100 ft. radius. This is, of course, a much more accute bend than is encountered on a normal road. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||