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).
Reasons for standardizing Aerolite pistons on Bentley vehicles.
| Identifier | ExFiles\Box 87\2\ scan0140 | |
| Date | 28th February 1936 | |
| To Sg.{Arthur F. Sidgreaves - MD} from Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} c.c. to WOF. c.c. to E.{Mr Elliott - Chief Engineer} c.c. to Da.{Bernard Day - Chassis Design} c.c. to Hx. c.c. to Cx.{Major Len W. Cox - Advertising Manager} Aerolite Pistons. We note that in the minutes of the last Conference, at which we were not present, under a reference to "Proprietary Articles" the statement is made that we appear to have gone astray over the use of Aerolite Pistons on the Bentley. We are interested in this statement because we were responsible for introducing Aerolite Pistons. Our only anxiety is that when a proprietary article is introduced on one of our chassis, it should have a fair deal. Experimentally we are always more severe in our testing on any bought-out article than we are on Rolls-Royce manufactured and designed parts, because we know that the former are likely to be more severely criticised. The reasons why we standardised the Aerolite pistons on the Bentley are as follows :- (1) Mechanical strength. (2) Improved oil consumption. (3) Improved power output and mechanical efficiency. (4) In addition, on the big bore engine the Aerolite piston has the advantage of being 2 ozs. lighter than the fully split piston. A light piston means a smoother engine on the over-run and less bearing loads. Taking these features in order - (1) Mechanical Strength. This has been dealt with in Hs.{Lord Ernest Hives - Chair}1/WJ.12.2.36. Since the Aerolite piston was introduced we agree that our own piston has been strengthened up, and actually, in the hands of customers, no trouble has been experienced from this feature. The trouble, however, which we had with our standard piston is emphasized from the list of 10,000 miles tests attached. At the present moment it is still a fact that on our endurance test bench running the Aerolite piston is stronger mechanically than our latest fully split skirt piston. | ||