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).
Aero engine starting motors, comparing Bijur and Bosch models and emphasizing reliability.
| Identifier | ExFiles\Box 23\2\ Scan054 | |
| Date | 29th May 1930 | |
| Contd. -2- R5/G29.5.30. You will remember that in all the aero engine work the engines were started by turning them at an exceedingly slow speed and we have received no complaints about the difficult starting of R-R aero engines, so I should like you to follow our standard practice asnear as possible. Apparently we can have the Bijur motor either wound to a slower speed or a slightly higher ratio of gear. One might think that probably the Bijur is wound for too high a speed, and the Bosch for too slow a speed. Therefore, in using the Bijur one would stick to the gear ratio of not less than 23.3 to 1. Above all things we feel this electric appar- atus must be thoroughly reliable, which may necessitate even a larger number of parts used in the construction. R.{Sir Henry Royce} | ||