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).
Rating test report for a Spectre engine suspension rubber, detailing load versus deflection measurements.
| Identifier | ExFiles\Box 93\1\ scan0186 | |
| Date | 3rd September 1935 | |
| 3-9-35 SPECTRECodename for Phantom III ENGINE SUSPENSION RUBBER RATING TEST F87575 LEC 4462 INITIAL LENGTH OF RUBBER - 2.00" LOAD - LBS | DEFLECTION - INS 20 | .002 30 | .004 40 | .005 50 | .006 100 | .018 150 | .029 200 | .040 250 | .052 300 | .063 LENGTH OF RUBBER AFTER TEST - 1.998" hB{C. E. Harcombe} | ||