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).
Note on a 'B.V. (1st Ripple)' component with a straight front pan and frame thickness.
| Identifier | ExFiles\Box 99\3\ scan0028 | |
| Date | 24th May 1939 | |
| H24. Rm.{William Robotham - Chief Engineer} By/HEB{H. Biraben}-1/WB.{Mr Brazier/Mr Bell} 24-5-39 B.V. (1st Ripple) with Straight Front Pan. Frame .092 thick file 1022. | ||