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 between B.T.H. and Watford magnetos of lightened type for 'R' engines.
| Identifier | ExFiles\Box 43\4\ Scan180 | |
| Date | 20th September 1929 | |
| X4021 To R.{Sir Henry Royce} from EFC. c. Sg.{Arthur F. Sidgreaves - MD} c. E.{Mr Elliott - Chief Engineer} Wor.{Arthur Wormald - General Works Manager} c. Ev.{Ivan Evernden - coachwork} Rg.{Mr Rowledge} c. EP.{G. Eric Platford - Chief Quality Engineer} Hs.{Lord Ernest Hives - Chair} EFCl/AD20.9.29. X.4513. B.T.H. AND WATFORD MAGNETOS OF LIGHTENED TYPE ON OR FOR "R" ENGINES Handwritten notes: X4021 X2832 X4513w X4513a Relatively early before the Race, B.T.H. magnetos were decided upon because the earlier models of Watford magnetos for "F" engines suffered from certain defects not apparent in B.T.H. machines for "F" engines. This was unfortunate for Messrs. North, particularly in view of the fact that their later machines for "F" engines and "R" engines showed such great improvement as to put them easily, in our opinion at the time of decision, in the running in comparison with the B.T.H. Now, following the experience we have had with the B.T.H. and Watford "R" engine machines, the position is that the Watford machines generally and "R" machines in particular, have good claim to superiority over the respective B.T.H. machines. In all, eight pairs of B.T.H. lightened type SC.12/9 magnetos and two pairs of Watford lightened type SP.{Mr Spinney}12/5 magnetos were received for use on "R" engines. Of these, seven pairs of B.T.H. and one pair of Watford, have been used. The B.T.H. magnetos were made with magnesium alloy castings throughout, whereas Messrs.North would not adopt | ||