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).
Engine tests with different airscrews to investigate and reduce gear rattle periods.
| Identifier | ExFiles\Box 179\2\ img261 | |
| Date | 18th February 1932 | |
| -2- Hs{Lord Ernest Hives - Chair}/Yng.4/SJ.18.2.32. Cont'd.{John DeLooze - Company Secretary} (3) For this Series of tests the engine was rebuilt with spring blades E.30827 and mounted on a hangar test stand. A 'light' airscrew was fitted and the engine run up to 3000 R.P.M. in order to see if there were any periods which could possibly be met with in an aircraft. No periods were found. A Fairey Metal Airscrew was then fitted and the gear rattle period located. This proved to be at approx. 760 RPM. An endurance test of ten hours was then run off. This was carried out in two parts, eight hours at 2250 RPM. using an airscrew absorbing 472 H.P., followed by two hours on gear rattle period 800 - 840 RPM. with the same airscrew. Strip. When the drive was stripped it was found to be in excellent condition except for slight fretting on the spring blades where they had been in contact with the driving side of the drive tongues. SUMMARY. As regards the alteration of the torque characteristic. We have a direct comparison of this using the same Fairey airscrew on Kestrel 11 - S - 25. On the standard engine gear rattle occurred at approximately 850 RPM. whilst with the engine having the spring drive fitted the rattle period was reduced to approximately 750 RPM. The gear has now been approved by the A.I.D. for tests in the air, and so will be fitted to an engine and tried out at Tollerton at the first opportunity. Ra/H.R.Young. Attached 281 "F". 284 "F". 285 "F". Also one photograph. | ||