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).
Potential design issue with a connecting rod joint, comparing it to Falcon and Eagle engines.
| Identifier | WestWitteringFiles\A\November1917\ Scan7 | |
| Date | 26th November 1917 guessed | |
| 2 Mr Royce gathered from Mr Bailey that the corner radius was only a small one .075 between the ears and the rod & that this probably accounted for the break even with a pin which is probably tight at each end. This radius on the contrary is .125 on the Eagle. I believe that the explosion pressure breaks the ear & that had there been any trouble due to local flexure of the case of the ears as indicated above it would have shown itself in the white metal. (Rad on Falcon is .075) It was also thought that the new pin was not as good as we believed owing to the possibility of the ear coming slack by deflecting endways. I do not agree with this. Since the angle of the cone is miles inside the "angle of repose" of the material & any load on the articulated rod would create much more friction than is required to prevent the ear sliding down the cone. I think you will find it impossible to break the new joint however badly put together, with a test, which is decisively destructive on the old joint. I send you these few notes with the object of keeping in touch with the job. AE. | ||