Two graphs comparing spring rating tests, one showing the effect of pad width and the other comparing different spring systems.
| Identifier | ExFiles\Box 43\2\ Scan163 | |
| Date | 27th May 1926 guessed | |
| (5) SPRING RATING TESTS. (δ) AND (α) EFFECT OF PAD WIDTH 21° SHACKLE RATING LBS./IN. TOTAL LOAD. LBS. α = WIDE PAD δ = NARROW PAD WORKING RANGE 1100 LBS. (6) SPRING RATING TESTS. (α) AND (E) COMPARISON OF SPRING SYSTEMS RATING LBS./IN. TOTAL SPRING LOAD. LBS. α = WIDE PAD 21° SHACKLE E = NARROW PAD VERTICAL SHACKLE WORKING RANGE 1100 LBS. | ||
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).