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).
Record of a vibration test on a '1400 type' engine, listing engine RPM, MPH, and observed vibration levels.
| Identifier | ExFiles\Box 25\3\ Scan010 | |
| Date | 25th January 1939 | |
| R.R. 148 (20m)(P. 689.14.11.10) G 1939. [Illegible crossed out text] John & Iles a Test 25/1/'' 4160 Vibrations on list engine as shown X6324 on water in a tin fixed to cylinder on 1400 type engine 22 gear Engine revs M.P.H [Crossed out: 880-780.] 26 - [Crossed out: slight] decided 920 33 N. slight 1000 36 [Crossed out: bad] [Crossed out: Very decided] 1150 41.5 V Slight. 1200 43 - Very Decided. 1300 & 1350 46.5 Bad. 1400 50.5 1600 & 1700 57 V.{VIENNA} Bad. (over rev for 1600) [Sideways text in left margin:] on [Illegible text] John by feel Rest (doubtful) | ||