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).
Headlight bulb power restrictions due to black-out regulations and sourcing 36-watt bulbs.
| Identifier | ExFiles\Box 167\1\ img358 | |
| Date | 1st April 1940 | |
| S/L Gry{Shadwell Grylls} Rm.{William Robotham - Chief Engineer} Elect. 611b Hn{F. C. Honeyman - Retail orders}4/ES.1.4.40. Headlights. With regard to the restrictions on headlights imposed by the black-out regulations, you are doubtless aware that amongst other things the power of the bulbs is supposed to be limited to 36 watts, although more powerful bulbs may be used when the condition of the reflectors, etc., is such that the illumination does not exceed a certain standard. Hitherto we have been unable to obtain 36 watt bulbs suitable for the R.100 headlights standardised on the later Bentleys, Wraiths and Phantom III's, and consequently have been compelled to continue to run such cars with more powerful bulbs. Lucas have now produced a suitable 36 watt bulb and we have ordered enough for the cars we are using down here, as we do not want to risk the possibility of trouble through using more powerful bulbs. You might like to look into the matter so far as your cars are concerned, ordering direct from Lucas any 36 watt bulbs you may want. Of course, it would be advisable to specify the type of headlight into which they are to be fitted. We suggest that in any case a pair of 36 watt bulbs and a couple of spares might be obtained for Sg{Arthur F. Sidgreaves - MD}'s Wraith, unless it should happen this is already fitted with such bulbs. Hn.{F. C. Honeyman - Retail orders} Ack only 2/4/40. | ||