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 fuel pump performance, referencing tests MT.200 and MT.201.
| Identifier | ExFiles\Box 149\3\ scan0153 | |
| Date | 28th October 1940 guessed | |
| - 3 - It will be seen from MT.200 that the delivery - speed curve generally confirms the one supplied by the makers, although it begins to deviate from the straight line at a lower pump speed; this is however probably due to the variation in pipe restriction in the two tests. It has been established in previous tests that with the standard rig system excessive restriction is offered by the pipes at flows exceeding about 3400 pts/hr. It is also evident from these curves that the delivery for a given pump speed is approximately 35% above that of the standard Merlin fuel pump. With the special bye-pass valve out of action a slightly higher delivery was obtained than with it in operation; it would appear therefore, that its incorporation is hardly justified. MT.201 indicates that the performance at altitude should be slightly better than that of the Merlin pump, but the improvement might not be maintained on a production basis. The weight of the pump is 5 lbs 13 oz. compared to 8 lb. 6 oz. for the Merlin. The speed at which pumping commenced with unrestricted suction and delivery was found to be 125 r.p.m; the corresponding speed for the Merlin pump is approximately 100 r.p.m. The power required to drive the pump was practically negligible, being about .15 HP at its maximum speed, 2400 r.p.m. The following table compares the pump with the standard Merlin fuel pump and the Pesco - Merlin pump type F8. P.T.O. | ||