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).
Graph comparing the critical ATS temperature for a spring-tensioned fan versus a positively tensioned fan belt at 62 MPH with no bonnet ventilation.
| Identifier | ExFiles\Box 64\1\ scan0077 | |
| Date | 25th June 1931 guessed | |
| GRAPH V.{VIENNA} 19 E.X. 62 M.P.H. No BONNET VENTILATION COMPARISON OF SPRING TENSIONED FAN AND FAN BELT TENSIONED POSITIVELY. CRITICAL ATS TEMP 40°C 30°C 20°C 10°C SPRING TENSIONED 40.5 BELT TIGHTENED CHOC à BLOC 44.5 | ||