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).
Secret internal memorandum regarding the hydraulic brake specifications for the 'Myth' project.
| Identifier | ExFiles\Box 110\1\ scan0006 | |
| Date | 3rd September 1940 | |
| SECRET. Rm{William Robotham - Chief Engineer}/Rigby from Ev.{Ivan Evernden - coachwork} c. to Rm.{William Robotham - Chief Engineer} c. to Rm{William Robotham - Chief Engineer}/FJH.{Fred J. Hardy - Chief Dev. Engineer} c. to Rm{William Robotham - Chief Engineer}/EAG. c. to Ev{Ivan Evernden - coachwork}/DB.{Donald Bastow - Suspensions} re Hydraulic brakes - Myth. As requested by Rm.{William Robotham - Chief Engineer} we are contacting you on the question of hydraulic brakes for Myth. It is essential that we should co-ordinate our views and finalise our requirements before Mr. Parnell of Lockheeds pays us a visit next week. Below we give a table of the characteristics of the car to enable you to form your conclusions. It must be realised that figures for such items as the weight and the position of the centre of gravity are estimates based on E.V. Wheelbase 99.000 ins. Track front. 50.000 ins. Track rear 51.500 ins. Rolling radius of wheel - tyre 13.000 ins. Weight of car - unladen 2240 lbs. Height of C of G (laden 4 passengers) 24.000 in. above ground. Longitudinal position of C. of G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 55.500 in front of rear wheel Pedal length 10.000 ins. Maximum pedal stroke brakes worn at centre line of plate 4.500. We have projected 10 ins. dia. drums and shoes 1.500 wide. We hope to place the master cylinder, which we suggest should be of the tandem type, in front of the brake pedal operated by a compression rod from some point on the pedal lever between the fulcrum and the pedal plate, see PL.301 size 5. It is suggested that the hand brake should consist of a plate type toggle lever operating the shoes and pulled by a cable, using the American type equalisers. We shall welcome your recommendations. | ||