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).
Failure of the 'Goshawk II' hand brake and a proposed design change to the brake shoe.
| Identifier | WestWitteringFiles\G\October1921\ Scan68 | |
| Date | 19th October 1921 | |
| To HS.{Lord Ernest Hives - Chair} from R.{Sir Henry Royce} Copy to CJ. " " WOR.{Arthur Wormald - General Works Manager} " " DA.{Bernard Day - Chassis Design} " " BY.{R.W. Bailey - Chief Engineer} ORIGINAL. R1/G17/10/21. RE "GOSHAWK II" HAND BRAKE. X4253 With reference to the brake strap belonging to the hand brake being destroyed, we notice that this has come about due to the Ferodo crushing or wearing at the end of the brake strap, this causing a very heavy bending strain to fall on the brake shoe. Unless the testing of the brake is excessive, it would be advisable to make this brake shoe of somewhat different design or different material. Owing to the fact that this brake can be notched up, it is possible that an excessive strain can, under the condition of your test, fall upon the shoe due to expansion or the movement of the axle. I do not think, however, that this had much to do with the broken shoe but the cause is, wearing away of the ferodo on the ends of the shoe. We are sending a drawing shewing an increase in the section, such as will considerably reduce the maximum stress of the inside edge of the brake shoe. The shoes for the foot brake need not apparently, be altered, as these cannot be so violently treated, and also the operating connecting rods cause the pressure to fall less disastrously upon the shoe. YNR R.{Sir Henry Royce} RECEIVED OCT 19 1921 H H 2827 (90 L) QF H S20' 18-5-21) C' 2002 | ||