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).
Testing and standardisation of Lucas WT.13 type horns.
| Identifier | ExFiles\Box 166\9\ img153 | |
| Date | 13th January 1938 | |
| To Roy{Sir Henry Royce}/Mills from Rm{William Robotham - Chief Engineer}/RC.{R. Childs} c. By/RD. 6066 horns Rm{William Robotham - Chief Engineer}/RC.{R. Childs}2/WH.13.1.38. RE LUCAS WT.13 TYPE HORNS. As the real test of horns with respect to moisture in the trumpet and the volume of sound can only be obtained at high speeds, we cannot standardise our WT.13 type horns until endurance tests have been carried out on 20.G.VI. If we cannot obtain sufficient pairs for the first six Wraiths, WT.11.X should be fitted and changed over at a later date. Rm{William Robotham - Chief Engineer}/RC.{R. Childs} | ||