Material properties for Wraith and Phantom III fan blades.
| Identifier | ExFiles\Box 8\9\ 09-page28 | |
| Date | 19th February 1938 | |
| To By. {R.W. Bailey - Chief Engineer} From Rm {William Robotham - Chief Engineer} /Std. c. Da. {Bernard Day - Chassis Design} c. RHC. {R. H. Coverley - Production Engineer} c. Roy. {Mr H. Royce - Buyer} Rm {William Robotham - Chief Engineer} /Std.3/MH. {M. Huckerby} 19.2.38. WRAITH FAN BLADE MATERIAL AND PH.III. 624 Further to our Rm {William Robotham - Chief Engineer} /Std.9/AP.4.2.38 we have examined the Wraith fan fitted with aluminium blades (drg. specification A.223.A) and the blades showed no sign of distortion. However, an examination of the fan, sent herewith, will show these blades are very soft and would be distorted if the fan were at any time used to turn the engine. We have now, however, obtained a sample of the material in which the suppliers (Coventry Radiator and Press Works Co. Ltd.) will make the blades to our drawing EW.1514 and send you same herewith. It will be seen that this material is very much stiffer and stronger than the material we have tested (although presumably to the same specification) and is generally similar to the first aluminium fan blades which we tried. We think this material will be quite satisfactory from all points of view for these fan blades and accordingly the current order need not be held up any longer. We think, however, that our Laboratory should examine the sample and specify a minimum strength or hardness figure to ensure that the standard of the sample is maintained. This should be added to the detail drawing. We expect to use the same material for Ph.III fan blades, but would like these held up if possible until we have completed further tests on same. Rm {William Robotham - Chief Engineer} /Std. | ||
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).