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).
Letter to North & Sons Ltd. regarding the return of four IS12 aero magnetos for comparative testing.
| Identifier | ExFiles\Box 43\4\ Scan104 | |
| Date | 8th December 1927 | |
| BY.{R.W. Bailey - Chief Engineer} Mailing. V4021 Expl. Dept. EFC8/T. 8th December, 1927. Messrs. North & Sons Ltd., Whippendell Road, Watford. Dear Sirs, AERO MAGNETOS: We are now referring particularly to the four aero magnetos type IS12, Nos. 83119/20 and 83132/3, which Mr. North took away with him from our Experimental Department at the end of August. We are quite aware of the fact that it has been mutually agreed that it would serve no particular purpose to have these brought up-to-date and returned, in view of the fact that you are producing newer magnetos. However, if convenient to you, we would like to have these put into condition and returned to us for a special reason, viz. that we are having a certain amount of trouble with breakages of drives on magnetos of the other type which we have under consideration. The moment of inertia of the rotor of this other type is 50% greater than that of the rotor of your magneto, and we are anxious to determine the extent of the reduction of the liability of the drive to fail with your magnetos as compared with these others. Is it possible to let us have these magnetos back in working order, it being understood that no serious modification with a view to overcoming previous troubles will have been made, for instance, we do not expect the change of range, unless readily altered. Yours faithfully, FOR ROLLS-ROYCE LIMITED. | ||