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).
Hollow-head valves, supercharger designs, and fuel injection systems for aircraft engines.
| Identifier | ExFiles\Box 178\2\ img078 | |
| Date | 4th March 1940 | |
| Serial No 4 page 2 Rm.{William Robotham - Chief Engineer} page 3 OYS/P/Mar 4 40 He obviously believes that an engine (like the R.R. or Allison, which cannot use a hollow-head valve, is missing something of considerable importance. Is having a session of the A.S.T.M. here on Wednesday on valve steels, which Lessels will attend and which will prove informative. I enclose copy of his blueprint. The most startling statement is on page 25, that valve temperatures at full loads are generally much lower in aircraft engines than in automobile engines. The paper appears to be an exhaustive catalogue of existing practice and I am sure will interest Ll. Smith and others. 3) Supercharger He does not know the Bessler supercharger, about which I just wrote you. Doubts whether Cooper-Bessemer have anything suitable for spark ignition aero engines. The Daimler Benz 601 engine has a fluid flywheel supercharger drive in which part of the oil supply to the fluid drive is constant and the other part automatically controlled to give optimum boost at all altitudes, without two speed gearing. Harold Sinclair (whom you know) has had such a design for several years and has been offering it (he believes) to the aero engine industry. D.B. appears to have stolen a march on everyone by producing it. Pratt & Whitney, on the two speed supercharger, use two fluid flywheels to speed up the gears prior to the insertion of the friction clutches for either speed. They ran into immense difficulty with the slipping friction clutch, which, however, appears to work on the right. (Harold Sinclair has probably shown you his synchro-coupling and Fluid-flywheel combination... D.{John DeLooze - Company Secretary} Heron is the only man here who knows anything about Cotal box, saying it has been used successfully with fluid flywheel on French railway cars. 4, Injection S.D.H. explained some of the history behind the concerted attack on Wilkinson in the IAM meeting on Aircraft Diesels. Wilkinson had published some pretty strong accusations of American engine builders for “clinging to gasoline”. General belief is in "safety fuels" rather than Diesel engines, for aircraft. Navy department has said it will use only diesels, but satisfactory diesels are not forthcoming. | ||