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).
Technical memorandum discussing chassis stiffening to address issues like fuss, roar, boom, and shimmy.
| Identifier | WestWitteringFiles\V\March1931-September1931\ Scan105 | |
| Date | 9th April 1931 | |
| FROM E.{Mr Elliott - Chief Engineer} Copy to Mr. Wor.{Arthur Wormald - General Works Manager} Hs.{Lord Ernest Hives - Chair} BY.{R.W. Bailey - Chief Engineer} DA.{Bernard Day - Chassis Design} [Stamp, faint: ORIGINAL] E1/T9.4.31. [Handwritten: 4634] FUSS, ROAR, BOOM AND SHIMMY. Assuming that no one would wish to use the engine for stiffening the frame, if it could be dispensed with, the deeper stiffer side channel offers a possibility of solution along these lines. We would suggest that the special significance in the use of the deep side channel lies in its ability to utilize the stiffness of the body to control the front axle. The use of deeper side members should not add particularly to the torsional rigidity of the chassis frame, but when the body is mounted a different state of affairs comes into being. The Maybach might be quoted in support of this argument, both the examples tried by us being reported as free from shimmy. On our own P.II chassis, a frame with side channels of double the present thickness, (with the existing dies, appears to be a considerable improvement. [handwritten] made Again, as negative evidence in favour, experiments to stiffen the front of the frame with a rigid cross using the existing side channels proved of very little benefit. Assuming body stiffness to preponderate, an increase of 50% in frame depth should increase the rigidity of the forward part of the frame about three times. [Stamp: RECEIVED 10 APR 1931] [Initials: H.S. E.{Mr Elliott - Chief Engineer}] | ||