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).
Design and effectiveness of different wing styles on experimental cars, focusing on the mud 'lip' for cleanliness.
| Identifier | ExFiles\Box 18\2\ Scan036 | |
| Date | 1st October 1928 | |
| X7390 To DA.{Bernard Day - Chassis Design} from Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}2/LG4.10.28. WINGS - N.SCH.2691. X7390 Y8390 We note that you have shewn Continental type wings on N. scg. 2691. We have had altogether four sets of such wings on experimental cars. With two sets, those on 16 and 17-EX, we have not had much experience because we hardly ran 16-EX at all, and 17-EX has only been used in fine weather. 10-EX wings, however, have proved themselves to be far the most effective for cleanliness, while Brooklands tests shewed them to be very good for windage. The whole secret appears to lie in the mud 'lip' of the wing because 15-EX wings though much the same shape as 10-EX but larger and longer in the tail, xxxxx and reinforced by a continuous tool box, proved themselves to be most unsatisfactory. The main difference seems to be that, for appearance, the outer edge of the wing was rolled over more on 15-EX and the mud 'lip' made practically horizontal with the ground. The consequences of this appeared to be :- (1) Liquid mud collected in appreciable quantities on the underside of the horizontal portion of the lip and was blown off the edge of the wing on to the body. (2) The liquid portion of the mud passing into the lip was blown away by the wind, but the solid portion was caught owing to the narrowness of the mud lip and the fact that it could not be shaken out by gravity since the bottom of the lip was horizontal. Thus the channel soon got filled up solidly and became ineffective. contd :- | ||