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).
Outlining the priority of various engine research and modification jobs.
| Identifier | ExFiles\Box 133\2\ scan0132 | |
| Date | 19th January 1935 | |
| To - E.{Mr Elliott - Chief Engineer} c. to Wor.{Arthur Wormald - General Works Manager} c. to Hs.{Lord Ernest Hives - Chair} With reference to our discussion on the 16th instant, with regard to priority of the various research jobs, you were going to let me have a report on the Air Ministry's request to alter the Aero Universal Unit top half to take larger cylinder bores than the unit was originally designed for, the size mentioned being a bore of 7" in association with the maximum designed crank of 6.6" stroke. You were then going to give me a report on the arrangement of the single cylinder test units asked for in my note Hs{Lord Ernest Hives - Chair}/Wd.{Mr Wood/Mr Whitehead}3/GB.1.1.35. We then decided to make the Single Cylinder requirements of the P.V.12 of the highest priority, the first step being to do the design work necessary to make the unit suitable for the 5.65" bore Merlin, as referred to in my note Hs{Lord Ernest Hives - Chair}/Wd.{Mr Wood/Mr Whitehead}1/GB.14.1.35. The first head to be of the ramp type. With reference to the design of this head, although our preliminary tests on the effect of increasing the clearance below the induction lip appears definitely to reduce the incidence of detonation attack, we think it desirable to design this head (and incidentally the similar type heads for the complete engine) with the original flat surface but with provision for chamfering back on both the exhaust and inlet lips, as may be required in the light of results we are now obtaining. Heads to follow are - the standard Pancake type, the open Penthouse as mentioned in my note Hs{Lord Ernest Hives - Chair}/Wd.{Mr Wood/Mr Whitehead}2/GB.14.135 and Penthouse with some degree of forced turbulence. The next in order of priority was the modification to the Bentley Universal Unit, modified to extend the crankshaft through both ends, as referred to in my note Hs{Lord Ernest Hives - Chair}/Wd.{Mr Wood/Mr Whitehead}4/GB.1.135. The other jobs in their order of priority are - | ||