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).
Issuing altitude power curves for the F.S. engine in Fairey 111F machines.
| Identifier | ExFiles\Box 36\2\ scan 213 | |
| Date | 6th May 1929 | |
| To Lr.{Mr Ellor} from Lr.{Mr Ellor} c. to RG.{Mr Rowledge} Ey. c. to Hs.{Lord Ernest Hives - Chair} Ey. c. to EF. Wor.{Arthur Wormald - General Works Manager} X2934 Lr{Mr Ellor}4/LG6.5.29. FAIREY 111F. MACHINES R.A.E. Replying to Lp{Mr Lappin}5/AV/Dl.5.29. We have decided to issue altitude power curves for the F.S. engine based upon the recent type test figures corrected according to A.M. instructions Appendix I of Addendum A.{Mr Adams} (AP.840). Although the rated altitude is fixed at 11,500 ft., it has been agreed between RG.{Mr Rowledge} and Major Ross that these engines may be subjected to a maximum boost pressure of + .8 lbs/sq.in. (15.5 lbs/sq.in. abs.) in the air. I have therefore prepared a set of altitude curves shewing the max. B.HP. available at various r.p.m. It will be noted that the full throttle height varies with r.p.m. and as the max. HP. is developed at 10,000 ft. (2500 r.p.m.) at + .8 lbs/sq.in. boost pressure, the airscrew should be designed for this altitude and not for 11,500 ft. which is the rated altitude. I personally think the power corrections asked for by the A.M. furnish slightly greater power than actually obtained in the air, but it is thought better to adhere to figures approved by A.M. for issue. Enclosed is a set of six prints for distribution Lr.{Mr Ellor} | ||