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).
Results from a rear axle bumper test and subsequent Brinell tests on various springs.
| Identifier | ExFiles\Box 119\2\ scan0105 | |
| Date | 14th June 1920 | |
| Contd. X1331 REAR AXLE ON BUMPER TEST. Total hours run on chassis. 11.6.20 | N.S. Spring - 4th. leaf cracked under clip. | 12 hrs. 14.6.20 | N.S. bolt F.419 main bearing bracket broken. | 13. hrs. 45 mins. | O.S. spring 2nd. leaf cracked 4th. and 5th. leaves broken under clip. | 17 " 15 " BRINELL TESTS. Spring F.7789. 2000 lbs. Leaves. | Brin: | Remarks. | Hrs. run. 1 | 388 | Cracked. | 14 hrs. 35 2 | 375 | O.K. 3 | 363 | Broken. 4 | 401 | O.K. 5 | 363 | Broken. 6 | 415 | O.K. Spring Y.363 1990 lbs. Leaves. | Brin: | Remarks. | Hrs. run. 1 | 401 | O.K. | 17hrs. 15 mins. 2 | 388 | O.K. 3 | 401 | O.K. 4 | 388 | Cracked. 5 | 388 | O.K. 6 | 375 | O.K. Spring F.7790 2100 lbs. Leaves. | Brin: | Remarks. | 14 hrs. 35 1 | 401 | Broken 2 | 363 | Cracked. 3 | 388 | O.K. 4 | 401 | Cracked 5 | 401 | " 6 | 388 | O.K. Spring Z.363 2120 lbs. Leaves. | Brin: | Remarks. | 17 hrs. 15 mins 1 | 415 | O.K 2 | 388 | Cracked 3 | 401 | O.K. 4 | 401 | Broken 5 | 388 | " 6 | 388 | O.K. | ||