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).
Summary table documenting spring failures, including position, fracture details, and material properties.
| Identifier | ExFiles\Box 119\2\ scan0249 | |
| Date | 7th April 1925 guessed | |
| -3- SUMMARY OF SPRING FAILURES. Ref. No. | Running time. | Position on chassis. | Position of leaf. | Position of fracture. | Compression | Rebound | Thickness | Brinell. | Type. ---|---|---|---|---|---|---|---|---|--- 044 | 20 - 4 | N/S | Top | 2½" to rear | 1.750 | 2.000 | .284 | 388 | Firth F.71980 045 | 21 - 34 | O/S | Top | 2" to rear | 1.750 | 2.000 | .290 | 388 | Firth F.71981 046 | 26 - 36 | N/S | Top | Rear of rear 'D' clip. | 2.250 | 2.562 | .283 | 383 | Firth F.71980 047 | 55. - 25 | O/S | 5th. from top 3rd. from top. | 4½" to rear 3¾" to rear | --- --- | --- --- | .234 .209 | 388 363 | Firth F.71981 048 | 36 - 20 | N/S | Top | 4" to rear | --- | --- | .289 | 388 | Firth F.71980 049 | 43 - 23 42 - 13 | O/S | Top 2nd. from bottom | 1¾" to rear 1" to rear | 2.000 --- | 2.200 --- | .290 .230 | 363 388 | Firth F.71981 050 | 13 - 50 | N/S | Top | 2½" to rear | --- | --- | .284 | 341 | Woodhead F.71790 051 | 13 - 50 | O/S | 3rd. from bottom | 6" to rear | --- | --- | .226 | 388 | Woodhead F.71791 052 | 39 - 25 | N/S | Top 4th. from top. Bottom | 2" to rear 2" to rear 1" to front | --- --- --- | --- --- --- | .288 .228 .205 | 388 415 388 | Firth 71980 | ||