Two graphs comparing spring rating tests, one showing the effect of shackle angle and the other comparing spring systems.
| Identifier | ExFiles\Box 43\2\ Scan160 | |
| Date | 27th May 1926 guessed | |
| TOP GRAPH: (1) SPRING RATING TESTS (β) AND (α). EFFECT OF SHACKLE ANGLE. WIDE PADS. Y-AXIS: RATING LBS/IN. X-AXIS: TOTAL LOAD LBS. LEGEND: α - 21° FORWARD SHACKLE β - VERTICAL SHACKLE. ANNOTATIONS: WORKING, RANGE, 1100 LBS BOTTOM GRAPH: (5) SPRING RATING TESTS. (δ) AND (β) COMPARISON OF SPRING SYSTEMS. Y-AXIS: RATING LBS/IN. X-AXIS: TOTAL LOAD LBS. LEGEND: δ - NARROW PAD. 21° SHACKLE β - WIDE PAD, VERTICAL SHACKLE. ANNOTATIONS: 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).