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).
Brake test results for an R.R. Goshawk 2 starter motor with brushes 75% advanced.
| Identifier | ExFiles\Box 35\4\ scan 101 | |
| Date | 22th February 1922 | |
| MOTOR FORM 5. With brushes 75% advanced. 2 X.3009. BRAKE TEST OF STARTER MOTOR. Date:- 22.2.22. Motor under test:- R.R. Goshawk 2 Dia. of brake wheel - 10" No:- 2 Weight of pan and portion of rope= 4 lbs. 14 ozs. Reduction gear ratio - | Load in pan (W) | Spring balance reading. (B) | Speed R.P.M. | Amps. | Volts. | W-S (lbs) | T-t (lbs) | Torque (lb-ins) | B.H.P. | E.H.P. | Efficiency. | |---|---:|:---:|---|---|---|---:|:---:|---|---|---|---|---:| | | lbs. | ozs. | | | lbs | ozs | | | | | | | 12 | 1 | 13 | 616 | 158.0 | 8.84 | 10 | 3 | 15.06 | 75.3 | .74 | 1.87 | .396 | | 11 | 1 | 10 | 650 | 150.0 | 9.00 | 9 | 6 | 14.25 | 71.3 | .74 | 1.81 | .408 | | 10 | 1 | 9 | 720 | 142.0 | 9.16 | 8 | 7 | 13.31 | 66.6 | .76 | 1.74 | .437 | | 9 | 1 | 9 | 780 | 133.0 | 9.34 | 7 | 7 | 12.31 | 61.6 | .76 | 1.67 | .455 | | 8 | 1 | 8 | 846 | 125.0 | 9.50 | 6 | 8 | 11.38 | 56.9 | .77 | 1.59 | .484 | | 7 | 1 | 4 | 920 | 119.0 | 9.62 | 5 | 12 | 10.63 | 53.2 | .78 | 1.53 | .510 | | 6 | 1 | 1 | 1004 | 111.0 | 9.78 | 4 | 15 | 9.81 | 49.1 | .78 | 1.46 | .534 | | 5 | 1 | 1 | 1116 | 104.0 | 9.92 | 3 | 15 | 8.81 | 44.1 | .78 | 1.38 | .565 | | 4 | 1 | 1 | 1180 | 98.0 | 10.04 | 3 | 5 | 8.19 | 41.0 | .77 | 1.32 | .583 | 19.5.21. 9 27-75 | ||