Design modifications and comparisons for the Wraith servo mechanism.
| Identifier | ExFiles\Box 9\4\ 04-page01 | |
| Date | 20th December 1934 | |
| To EH. from HDY. {William Hardy} C. Messrs. E. {Mr Elliott - Chief Engineer} Hs. {Lord Ernest Hives - Chair} Dev-RHC. {R. H. Coverley - Production Engineer} Wraith Servo. Wraith. N. Sch.4309 herewith shows the servo for the Wraith. The diameter of the friction surfaces is slightly greater than for the 20/25. The alternative methods of securing the friction fabric given on N. Sch.4289 for the Spectre(Codename for Phantom III) are equally applicable (when scaled down) to the Wraith. We have reduced the fork joint pins to .250 dia. in order to diminish the loss due to friction. We may have to modify the servo cam levers at a later date to suit the brake rod layout which has still to be determined. We have recently been asked in Hs {Lord Ernest Hives - Chair} /Rm. {William Robotham - Chief Engineer} 2/KW.17.12.34 to increase the area of the friction surfaces of the swinging arm in the case of the Bentley to secure a more consistent amount of friction. Consequently we shall be altering the schemes for the Spectre(Codename for Phantom III) and the Wraith in due course, to comply with this request, which will no doubt be equally applicable to them. HDY. {William Hardy} | ||
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).