Test report on the 3.EX (HAWK) Speedometer and Mileometer performance with varying tyre pressures.
| Identifier | ExFiles\Box 8\2\ 02-page43 | |
| Date | 1st June 1923 | |
| X613 1.6.23. 3.EX (HAWK(Aero Engine)) SPEEDOMETER. X3408 / X613 Speedometer records 1.7 m.p.h. slower at 30 m.p.h. with tyres at 90 lbs. per sq.in. than with tyres at 30 lbs. per sq.in. Mileometer. 7.4% fast with tyres at 90 lbs.per sq.in. 10.45% fast with tyres at 30 lbs. per sq.in. Hs {Lord Ernest Hives - Chair} /Rm. {William Robotham - Chief Engineer} | ||
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).