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).
Tests on Bentley headlamp and wing movement, and methods for reduction.
| Identifier | ExFiles\Box 82\4\ scan0021 | |
| Date | 20th November 1934 | |
| Be/Wym.{G. Harold Whyman - Experimental Manager}9/KW.20.11.34. Bentley Headlamp & Wing Movement. Further to our report Be/Wym.{G. Harold Whyman - Experimental Manager}16/KW.11.10.34, we have carried out another series of tests with regard to the above. In the first place our experience with 1-b-IV car when put on the vibrating machine at the Rover Car Works, showed us that the radiator could and did move under certain conditions and therefore our measurements taken relative to the radiator were liable to be slightly inaccurate. We therefore rigged up a very rigid framework from the dashboard (this being the most stationary point on the car) with a strip of paper across a plate attached to the front of it, and similar brackets carrying pencils as used on our previous tests, with one additional pencil to register radiator movement - photograph of measuring apparatus attached. The car was then run over a bad stretch of road at 30 m.p.h., the pencils recording the respective movements of head lamps, frame and radiator, relative to the dashboard, the figures given being the average of 3 runs for each test. In the first place the various fitments on the car had very little effect upon radiator movement, and as this is to all intents and purposes stationary when viewed from the driver's seat, we do not consider it worth recording. Summarising the results, the wings do have a steadying effect on the headlamps, and the one-piece wings are slightly better than the standard wings. The stabiliser is the biggest improvement, the dropped cross member is an additional benefit. The weight of this part has now been reduced to half the original figure without affecting its efficiency. The actual decrease in movement indicated on the attached chart does not always represent the full optical advantage obtained. This is because periodic movement is always more noticeable than the movement of similar amplitude well damped. With all our improvements we measured 35% reduction in headlamp flutter, but actually from the driving seat the benefit is at least 50%. RH{R. Hollingworth}/G.H.Wyman. | ||