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).
Data on the latest type Phantom II engines with balanced crankshafts for 40/50 engines in tanks.
| Identifier | ExFiles\Box 14\2\ Scan158 | |
| Date | 24th August 1933 | |
| X 7010 COPY. E.{Mr Elliott - Chief Engineer} from Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls} Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls}10/MA. 24.8.33. X.7770. X.7010. 40/50 ENGINES IN TANKS. replying to your E.8/HP.23.8.33., we send you the following data for the latest type P.II engines with balanced crankshafts. (1) (a) Polar moment of inertia of flywheel and clutch 1.3 slugs ft². (b) Polar moment of inertia of crankshaft 450 lbs. in². (c) Polar moment of inertia of Big Ends and pistons 210 lbs. in². (d) Polar moment of inertia of crank damper hub 20 lbs. in². (2) + Shaft stiffness 90,000 lbs. ft. per radian. (3) - Natural frequency of engine alone 200 per sec. or 3 per rev. at 4000 R.P.M. Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls} | ||