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).
Disadvantages and dangers of the headlamp dip and switch arrangement under certain driving conditions.
| Identifier | ExFiles\Box 61a\3\ scan0199 | |
| Date | 5th February 1936 | |
| WST 6/1/36 Wor.{Arthur Wormald - General Works Manager} c. Hs.{Lord Ernest Hives - Chair} By.{R.W. Bailey - Chief Engineer} ROY.{Sir Henry Royce} G/Rb.{R. Bowen} E.1/HP.5.2.36. re Headlamps. Replying to your memo Wor.{Arthur Wormald - General Works Manager}3/R.30.1.36, I am still of the opinion that the dip and switch arrangement under certain conditions is disadvantageous and even dangerous. The absence of illumination towards the centre of the road makes it very difficult when meeting badly illuminated heavy lorry traffic with high side lights where the road is narrow and weather conditions bad. It is difficult to know how near one is going and it becomes a matter of relying upon the off-hand side of the road and estimating that there is enough room. I have noticed this particularly when driving a Bentley fitted with dip and switch on parts of the Holyhead road which are narrow and very dark when it is wet, and also when meeting two lines of oncoming heavy traffic. The other point is that the absence of illumination already referred to becomes dangerous when overtaking on a dark wet night cyclists all over the road when those towards the middle become invisible, and also when overtaking vehicles at night time with protruding back loads above the sight line. It is not, I am of the opinion, sufficient to rely upon any illumination but that provided on the car. We would agree that the double dip and turn scheme does not always obtain respect from oncoming traffic, but in this relation I think the lamp makers are to blame for allowing stray light above the desired limit, and I think we ought to insist on the product being improved to overcome any objection from this source. I gather from Mr Cowen's memo that a plebiscite has been taken of Rolls-Royce car users, but it is not clear whether this refers only to people in and around London or whether it covers a wider area. If the former then I fear that the better lighted conditions round the London area may not show the necessities of the case to the same extent over a wider district, and also the average opinion may not cover the special conditions as cited above, which only arise on occasion. E.{Mr Elliott - Chief Engineer} | ||