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).
Graph showing torsional oscillation test results for a B.80 No 3 engine without a damper.
| Identifier | ExFiles\Box 132\1\ scan0135 | |
| Date | 28th March 1939 | |
| TORSIONAL OSCILLATION TESTS ON B.80 NO 3 (2.75" DIA SHAFT) NO DAMPER AMPLITUDE DEGREES ENGINE R.P.M. FIG. 2 JRS 28.3.39 | ||