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).
Blueprint detailing designs for a double piston damper and air vent ball valves.
| Identifier | ExFiles\Box 182\M19\ img080 | |
| Date | 1st June 1931 | |
| HS{Lord Ernest Hives - Chair} 369 1-6-31 DAS SCHEMES L.P. PASSAGE CHAMBERED OUT VALVE DIA REDUCED SPRING CHAMBER AIR RELEASE "DELCO" MAX .005" RADIAL CLEARANCE H.P. VALVE HOLE L.P. VANE HOLES VALUE VARIATIONS DOUBLE PISTON DAMPER AIR VENT BALL VALVES .161 DIA .075 DIA .095 DIA .156 DIA BALLS .1050 LIFT .125 DIA .300" ROLLS ROYCE LTD DERBY ISSUED 1 JUN 31 O.K. B.I.G. | ||