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).
Noted issues and suggestions following an examination of a Watford IS.12 magneto for the Falcon X engine.
| Identifier | ExFiles\Box 43\4\ Scan012 | |
| Date | 10th November 1926 | |
| To R.{Sir Henry Royce} from EFC. c. to BJ. Wor.{Arthur Wormald - General Works Manager} c. to Rg.{Mr Rowledge} By.{R.W. Bailey - Chief Engineer} c. to Da.{Bernard Day - Chassis Design} E.{Mr Elliott - Chief Engineer} X 4021 EFC3/T10.11.26. WATFORD IS.12 MAGNETO FOR FALCON X. X 4021/22 In addition to the points contained in the report Ha/Rm{William Robotham - Chief Engineer}2/LG9.11.26, from examination of one of these magnetos, concerning the running of which on the engine there has been a complaint, the following may be noted :- (1) A condenser breakdown occurred in one of the early machines. This was rectified by the makers. (2) It would be very convenient to have some simple method of disconnecting the primary for the purpose of timing the break. (3) The contact breaker cover is not located in such a manner as to ensure that when replacing, the earthing brush makes correct contact with the primary terminal plate. (4) We consider the failure of the contact breaker points is probably due to the ingress of oil. (5) Would not a polished aluminium finish be superior, as the enamel chips off very soon and gives the magneto an untidy appearance ? The above points, with the exception of (1), also apply to Watford type IS.16 magneto, in addition to which in the case of these other magnetos :- (6) We consider one of the safety spark gaps is too close to the armature winding. It is a similar arrangement to the early type of FO1 safety gap, which was liable to cause burning of the windings around the safety gap points. (7) We consider the screw securing the flexible to the outer distributor should be locked. Our general specification of performance of these magnetos for aero engines will be issued shortly. EFC. | ||