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).
Steering tests and modifications for the 'E' Series Phantom III, addressing low-speed wobble.
| Identifier | ExFiles\Box 95\1\ scan0495 | |
| Date | 27th June 1938 | |
| 350 To By.{R.W. Bailey - Chief Engineer} c. to Da.{Bernard Day - Chassis Design} Rm{William Robotham - Chief Engineer}/FJH.{Fred J. Hardy - Chief Dev. Engineer}16/JH,27.6.38. 'E' Series Phantom III Steering. As a result of the last 15,000 miles test on Phantom III, adjustable cross steering tubes were standardised for E series Phantom III. Actually, the parts that were standardised were for use with the existing standard suspension and are unsuitable for use with Wraith wheel movement suspension which is coming on at E series. We therefore need new details for adjustable tubes to suit the new suspension. We have now run a considerable mileage on 32 & 35.EX. with yokes to Rm.{William Robotham - Chief Engineer}383 given a castor angle of ½° instead of the standard 1°. The objects of this are to reduce the tendency to low speed wobble and to make the steering lighter on corners. These results have been obtained to a small extent and no disadvantages have been discovered. As low speed wobbles are a serious complaint on Phantom III we suggest that when Wraith wheel movement is introduced the castor angle should be made zero. This is the same as the angle we have tested within manufacturing limits. Rm{William Robotham - Chief Engineer}/FJH.{Fred J. Hardy - Chief Dev. Engineer} | ||