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).
Summarizing the results of wind tunnel tests conducted at Brooklands on a car model.
| Identifier | ExFiles\Box 160\2\ scan0126 | |
| Date | 23th June 1933 | |
| S/W. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}..from Ev.{Ivan Evernden - coachwork} Ev.{Ivan Evernden - coachwork}3/WT23.6.33. Wind Tunnel Tests at Brooklands. After you left me on Wednesday we made a test on the model fitted with Panhard type front wings, and a radiator very like the new Chrysler. We also filled in the gap between the wings and the radiator with a moderate radius. We tested this model with a 35° screen and the long tail, and were astounded to find that the figure for the drag was only 1.1028 lbs. This figure is only a little more than that for the standard car with no front wings, which was 1.1424 (struck through). This was the greatest benefit shown in all the tests. 1.0871. We then tried the same frontal shape with a 17° screen and a short tail, and the drag figure was then 1.1922 lbs, this showing that when the front of the car is made so that it does not set the air in a state of violent turbulence there is some value in a sloping screen and a tail. A full report of these tests will be written by me when in W., but I thought you would like to know this rather encouraging fact. The next move seems to be to rig up the second model which has a longer tail and is narrower in the body at the rear seat. This model with the modified front should show a very marked improvement. Ev.{Ivan Evernden - coachwork} [Handwritten note] I am away at Coventry to W. on Monday or Tuesday. I have got an office. Small though it is at Sales, & hope to soon get settled down to work. I shall do a design for a revised front on the lines indicated in the test | ||