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 of a gravity-operated suction pipe designed to supply oil to an engine during inverted flight.
| Identifier | ExFiles\Box 179b\4\ img062 | |
| Date | 13th April 1933 | |
| To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/Yng. to. Sg.{Arthur F. Sidgreaves - MD} Hor. to. Ag. Hy.{Tom Haldenby - Plant Engineer} to. Ir. EP.{G. Eric Platford - Chief Quality Engineer} to Mr. Jaques. Hs{Lord Ernest Hives - Chair}/Yng.1/KT.13.4.33. x2965. r3389. KESTREL CONNECTING ROD FAILURES. REPORT ON TESTS TAKEN WITH GRAVITY OPERATED SUCTION PIPE FOR INVERTED FLYING. Introduction. The object of this scheme was to provide a supply of oil to the engine immediately the aircraft resumed the normal attitude after inverted flight, without necessitating major alterations to the aircraft installation and the lubricating oil system of the engine. The best results during previous tests (see report ref. Hs{Lord Ernest Hives - Chair}/Yng.4/MJ.20.3.33) were obtained by diverting the scavenge pump oil to the delivery side of the pressure pump until the latter had reprimed itself and functioned normally. Details of scheme and tests. The scheme consisted of a suction pipe housed inside a Hawker Fury oil tank and located by an airtight sleeve or trunnion free to swivel in a vertical plane about a horizontal axis, the full movement of the pipe being restricted by an aluminium casing, see DES.1879. Tests were taken with the tank mounted on the invertable rig in two positions, viz:-- (a) at 90º to the crankshaft, similar to preceeding tests, (b) at 45º to the crankshaft. This condition was imposed in order to put an additional thrust upon the trunnion and note whether the suction pipe had a tendency to jamb for various positions of the tank. Tests were carried out with the engine running at 2250 RPM., an oil inlet temperature of 70ºc, and main oil pressure of 60 lbs/sq.in. On inversion the main oil pressure was maintained for 30 sec. when the engine was reverted to the normal attitude, the oil pressure remaining constant. It would seem that the period of maintaining oil pressure during inversion is solely dependent upon the quantity of oil in the tank. As the oil flow with the standard pressure pump is approx. 3 1/2 galls/min. and the capacity of the tank 4 1/2 galls., the period would be 73 secs. with a full tank. During a "roll" in a clockwise direction, the rig was held momentarily after having travelled through 90º, when the oil pressure quickly dropped to zero, the oil level being | ||