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).
Wing flap in relation to frame frequency on different car body types and axle ratios.
| Identifier | ExFiles\Box 88\2\ scan0079 | |
| Date | 12th December 1934 | |
| To Lp.{Mr Lappin} from Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} c. to Wor.{Arthur Wormald - General Works Manager} Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}4/KW.12.12.34. Trials Car. Replying to Lp.{Mr Lappin}7/LAM.10.12.34. Our experience has been that the alteration to the frame frequency on the open car eliminates wing flap, whatever type of wing is fitted. The same is largely true of drop head cars. It is only stiff Saloon bodies that cause the trouble. We entirely agree with you that higher axle ratios are most disappointing for English conditions. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||