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).
Tests to determine if the speedometer shews any lag in following up increase of speed.
| Identifier | ExFiles\Box 113\2\ scan0026 | |
| Date | 24th January 1923 guessed | |
| TESTS CARRIED OUT TO DETERMINE IF THE SPEEDOMETER SHEWS ANY LAG IN FOLLOWING UP INCREASE OF SPEED. Third speed. A.{Mr Adams} Readings. Start 10 m.p.h. Finish 28 m.p.h. Distance 177 ft. By time 3.85 f.p.s2 By speedometer 3.92 Error 2% B. Readings. Start 10 m.p.h. Finish 29 m.p.h. Distance 192 ft. Time 6.8 secs. By time 3.92 f.p.s2 By speedometer 3.96 f.p.s2 Error 1% + C. Readings. Start 10 m.p.h. Finish 28 m.p.h. Time 6.4 secs. Distance 178 ft. By time 4.14 f.p.s2 By speedometer 3.92 f.p.s2 Error 5% - D.{John DeLooze - Company Secretary} Readings. Start 10 m.p.h. Finish 29 m.p.h. Time 6.8 secs. Distance 192 ft. By time 3.988 f.p.s2 By speedometer. 3.97 f.p.s.2 Error 1/2% - Average error for accns. of 4 f.p.s. = 1% too little by speedometer. Second speed. A.{Mr Adams} Readings. Start 10 m.p.h. Finish 28.5 m.p.h. Time 6.6 secs. By time 4.3 f.p.s2 By speedometer 4.06 f.p.s2 Error 6% - B. Readings. Start 10 m.p.h. Finish 29 m.p.h. Time 6 secs. Distance 178 ft. By time 4.7 f.p.s2 By speedometer 4.5 f.p.s2 Error 5% - C. Readings. Start 10 m.p.h. Finish 30 1/4 m.p.h. Time 6 2/5 secs. Distance 192 ft. By time 5 f.p.s2 By speedometer 4.68 f.p.s2 Error 7% - Average error for accelerations of 4.5 f.p.s. is 6% too little reading by speedometer. Rm{William Robotham - Chief Engineer} | ||