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).
Test report on a Phantom III, including a comparative analysis of fan noise against a Cadillac.
| Identifier | ExFiles\Box 91\3\ scan0177 | |
| Date | 9th November 1935 | |
| Steadman x300a HOTEL DE FRANCE. CHATEAUROUX. Indre. France. To. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} From. G.W.H. 31. EX. PHANTOM III. This Car was finished yesterday noon, and after running the Engine for a short time in the garage, the Car went out on the road with a maximum load in the rear. The speed of the Car was kept down to 30 MPH. accelerating and decelerating, so that the bearings would have all possible chance of getting bedded in. Upon returning, the oil was thoroughly drained out and fresh oil put in. FANS. We took a comparative test in the garage with the Cadillac and R.R. fans, for the noise factor, flexibility, etc. The result was interesting from the flexibility point, as the statastic test gave such different results. The R.R. blades actually start earlier to deflex (approx. 40 MPH.) than the Cadillac. The total deflexion is greater by 10% than the Cadillac observed from a side view, no actual measurements taken. The Cadillac fan blades deflects 50% at maximum speed. Noise Test. CADILLAC. R.{Sir Henry Royce} R.{Sir Henry Royce} CADILLAC. 30 MPH. No audible noise Ditto 40 MPH. Just audible " 50 MPH. Slight hum " 60 MPH. Hum slightly increased " 68 MPH. Fan boom besides wind noise Not so noticeable 70 MPH. Hum clearly audible and could) be heard in driving seat. ) ....Ditto 80 MPH. Noise clearly defined and heard) distinctly in driving seat )...Higher pitched tone ...more noticeable These tests were taken in the quiet garage with Radiator shutters full open. The comparison is given listening in front of the Car and in driving seat all closed up. G.W.Hancock. G.W.H. | ||