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).
Aero engine reliability, comparing it with durability, and considering design choices for the Eagle and Super Eagle engines.
| Identifier | ExFiles\Box 43\1\ Scan059 | |
| Date | 2nd September 1924 | |
| To CJ. from R.{Sir Henry Royce} c. to RG.{Mr Rowledge} BY.{R.W. Bailey - Chief Engineer} HS.{Lord Ernest Hives - Chair} RE. AERO ENGINES . X.3989. X.1906. When Rg.{Mr Rowledge} was here I spent the greater part of a whole morning impressing upon him, E.{Mr Elliott - Chief Engineer} Hs.{Lord Ernest Hives - Chair} and myself the utmost importance of increased reliability in aero engines. I next said that we ought to not to attempt, or promise or undertake anything that made reliability less easy to obtain, such as spur gearing instead of epicyclic, inverted engines, extremely high weight HP. performance, etc. and that we ought to consider reliability quite distinct from durability, that is, where it causes repairs to be made, but does not cause break-downs. This I look upon as much less serious than reliability. During this discussion I was not aware that the Eagle lX. was less reliable than Eagle Vlll. I do not remember in which way this want of reliability has come into existance except perhaps by increase of speed. I can see that it would be best for BY.{R.W. Bailey - Chief Engineer} as production engineer, to draw up a report on each failure from his point of view so that we can say whether it is caused through the users want of care, the installation, production, materials, or the design. If this is done in both aero engines and car work none of us can take offence, and we ought to get at least another side of the question. Regarding the Super Eagle, I have induced RG.{Mr Rowledge} to abandon the idea of inverting this as standard, but suggested that we should build it as far as possible so that it can be inverted providing it works with equal satisfaction contd :- | ||