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).
Procedure for conducting a safety test on an engine, focusing on provoking and observing backfires.
| Identifier | ExFiles\Box 179\2\ img192 | |
| Date | 16th January 1932 guessed | |
| COPY. 7 - SAFETY TEST - (a) The inlet valves of one cylinder are set to remain open from 1 to 3 mm. (.040 to 120"). The engine is run from extreme slow running R/3 to nominal speed N. at speeds regularly increasing and remaining one minute at least on 6 points of the power consumption curves at various RPM. as determined in test No.6. The engine is then run for five minutes at the worst speed for backfires; this run is followed by an acceleration test. The time taken for acceleration and the backfires produced are noted down. (b) a similar test is carried out with two high tension wires of one magneto crossed over any of two cylinders, the other magneto being switched off. (c) Attempt to provoke backfires are made for 5 minutes as follows :- (1) - By weakening the mixture, either by reducing the fuel supply or by operating the altitude control. (2) - By switching off and on again without moving the throttle. The following results should be obtained - (1) - No flame should develop outside in the course of the above tests. (2) - The engine inspection carried out after these tests should not show any signs of damage, strain, overheating, gumming up, which might upset the good running. (3) - A one hour verification test is carried out at 9/10 of nominal power. | ||