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 considerations for a two-cylinder experimental 'V' Condor engine.
| Identifier | ExFiles\Box 180\M2\M2.1\ img007 | |
| Date | 24th March 1918 | |
| To D.A. from E.{Mr Elliott - Chief Engineer} Copy to DY.{F R Danby} " " H.{Arthur M. Hanbury - Head Complaints} " " R.H. " " EPC. ORIGINAL RECEIVED X. 3257 RE TWO-CYLINDER EXPERIMENTAL "V" CONDOR ENGINE. With reference to the above Mr. Royce has asked me to send you certain information concerning the lines on which he would like you to alter this engine. The intention was to make a very simple crankcase of straight line wall and web design, which would be quick and cheap from the pattern maker's point of view. This crankcase was to be an exact reproduction of one cell of the 12-cylinder design. If there is any doubt about the length of the cell being short, a redundant cell should be added to create stability. I attach herewith a rough sketch showing a one-cell crankcase with the feet formed naturally by the transverse webs. There seems to be a fair amount of stability longitudinally, and this is increased by attachment to a large base on the test rig. The weight of the flywheel seems relatively a small consideration compared with the "out-of-balance" forces which have to be withstood, and which exists symmetrically around the centre line of the cylinders in the plan view, and which therefore do not ask for any longitudinal stability to speak of. This "out-of-balance" force may, or may not, coincide with the centre of gravity of the engine. This is where there seems to be the only probability of a rocking couple. | ||