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 discussing the physics of car handling, focusing on lateral forces, skidding, and stability during turns.
| Identifier | ExFiles\Box 24\1\ Scan044 | |
| Date | 12th December 1931 guessed | |
| 10. usually assumed, the limiting lateral force at which side slip occurs is proportional to the applied weight on the wheel there will obviously be a maximum curvature of path round which a car can turn with safety at each speed and for a given condition of road surface. If turned more sharply skidding or sideslip will occur but the tendency to skid will be equal as between both front and rear wheels, and is entirely unaffected by the distribution of weight along the length of the car. If the position of the centre of gravity is nearer the rear wheels, for instance, the centrifugal force will be greater in exactly the same proportion. Now consider the effect when the car is moving uniformly in a curved path as above and commences to straighten out again for it is this phase of the movement which is the critical one at which tail swing or skidding usually occurs. The effect of turning the front wheels for the purpose of straightening out is to subject the car to an additional lateral force in the plane of the front wheels. A lateral shearing reaction exists between tyre and ground due to centrifugal force and the direction of this new lateral force is to reduce this shearing reaction and therefor the liability of the front wheels to sideslip. Now consider the orthodox car in which K² is much less than AB. In this case if a lateral force is applied to the front wheels a lateral force acting in the opposite direction must simultaneously occur in the plane of the rear wheels. But since the direction of the component of centrifugal force is the same for both front and rear wheels this latter force must increase the lateral shearing reaction in the plane of the rear wheels. If the car is already turning on a curved path with little margin of adhesion this additional force will probably cause a definite | ||