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).
Two graphs showing spring rating tests, one for the effect of shackle angle and the other for the effect of pad width.
| Identifier | WestWitteringFiles\O\2April1926-June1926\ Scan164 | |
| Date | 27th May 1926 guessed | |
| TOP GRAPH: (2) SPRING RATING TESTS (S) AND (€) EFFECT OF SHACKLE ANGLE NARROW PADS WORKING RANGE S = 21° FORWARD SHACKLE € = VERTICAL SHACKLE Y-AXIS: RATING LBS/IN. X-AXIS: TOTAL SPRING LOAD. LBS BOTTOM GRAPH: (3) SPRING RATING TESTS (B) AND (€) EFFECT OF PAD WIDTH. VERTICAL SHACKLE WORKING RANGE 1100 LBS B = WIDE PAD. € = NARROW PAD. Y-AXIS: RATING LBS/IN. X-AXIS: TOTAL SPRING LOAD. LBS | ||