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).
Front axle tests concerning the effect of tyre contact offset on steering when braking on four-wheel brake cars.
| Identifier | WestWitteringFiles\P\October1926-November1926\ Scan006 | |
| Date | 1st October 1926 | |
| To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} c. to BJ. Wor.{Arthur Wormald - General Works Manager} c. to Rg.{Mr Rowledge} E.{Mr Elliott - Chief Engineer} c. to Da.{Bernard Day - Chassis Design} By.{R.W. Bailey - Chief Engineer} ORIGINAL Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}3./T1.10.26. FRONT AXLES. X7420 X8430 With reference to Da{Bernard Day - Chassis Design}3/M24.9.26. We have carried out tests on two front axles having the tyre contact arranged 2.6" and 5.75" out of centrepoint respectively. As a means of indicating the relative importance of various features of the axle, we wish to enumerate some of the results which we obtain with the present standard arrangement. Normally, there is never the slightest feeling on a RR. four-wheel brake car that the steering is affected when pulling up. In a crisis, however, when the brakes are applied with the steering on a lock, if the pivots lean forward, the wheel is wrenched out of the driver's hand and the steering runs over on to full lock. Naturally, the efficiency of the front brakes has a considerable influence on this phenomena. Nevertheless, even knowing what is likely to happen, experimental and test drivers have been off the road a number of times due to this feature of thebrakes. Several accidents to customers cars have been brought to our notice which, in our opinion, may have been attributable to the steering taking charge. The instruction book tells the customer that the brakes should not be applied when rounding a corner. It is a fact, however, that there are several cars on the market, among them the Lancia, with which the most violent brake application on a lock does not have the slightest effect on the steering. Contd. | ||