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).
Comparison of engine performance curves and automatic advance characteristics.
| Identifier | ExFiles\Box 37\1\ scan 268 | |
| Date | 27th August 1924 | |
| Contd. -3- EPC9/T27.8.24. This is put on tracing paper so that it may be compared by super-position with the curves for the 20 HP., from figures supplied by Hs.{Lord Ernest Hives - Chair} on 3.2.22, but the absolute position of this curve in relation to dead point is not now known, and as, in any case, only the one curve is given (i.e. not a maximum and a minimum), this curve can only be compared relatively, and with that limitation will be found reasonably to agree. (E.{Mr Elliott - Chief Engineer} will note that this curve of EP{G. Eric Platford - Chief Quality Engineer}'s refers to the 20 HP. engine and not to the EAC;2, with which we are more concerned at the moment). The above will answer the query contained in the 3rd par. of E's note. Referring to the fourth par. of E1/M9.8.24, the advance values contained in the report Hs{Lord Ernest Hives - Chair}9/LG28.4.21 quoted, were figures obtained for the Goshawk I engine, and are not the figures to which the 20 HP. curves now sent are drawn - these were later figures obtained on 3.2.22. We are also sending another group of curves (photostats) of automatic advance characteristics of the various units (apart from any hand advance) reckoned from a datum which in each case is the starting point of the automatic advance of that unit. This group of curves is also to the same scales as the above group, but photostatically reduced. | ||