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).
Specifications for 8' static deflection springs with an 850 lbs. normal load.
| Identifier | ExFiles\Box 154a\2\ scan0050 | |
| Date | 13th March 1939 | |
| ATTACHED TO Rm{William Robotham - Chief Engineer}/FWK.11/JH. 13.3.39. 8" Static Deflection Springs, 850 lbs. normal load. Wire diameter. 0.668". Mean diameter of coils. 5.332". Number of effective coils. 5 3/4 Normal load (at length 7.165"). 1495 lbs. Normal deflection. 4.56". Normal stress, uncorrect. 68,150 lb/in2. Maximum load (at length 5.635"). 1996 lbs. Maximum deflection. 6.09". Maximum stress, uncorrected. 91,000 lb/in2 Maximum stress corrected. 107,300 lb/in2 Free length. 11.725 Rate. 328 lbs/in. Rate at wheel (plain leverage assumed) 106 lbs/in. Room for packing. 0.50". | ||