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).
The procedure for tracking piecemeal modifications and specifications for cars and engines using L.O.P. numbers.
| Identifier | ExFiles\Box 161a\1\ scan0080 | |
| Date | 28th February 1940 | |
| -2- Rm.{William Robotham - Chief Engineer}2/MH.{M. Huckerby}28.2.40. From this point onwards the modifications to bring the car up to the final specification would be piecemeal. A copy of every instruction to modify the car would be sent to Ev{Ivan Evernden - coachwork}/HH. and a copy of a memo from RH.{R. Hollingworth} stating that the modification had actually been carried out, would be sent to Ev{Ivan Evernden - coachwork}/HH. At any time, therefore, Hunt would be in a position to produce a specification of what a car actually was at the moment in question. Exactly the same procedure would be followed with regard to engine units. L.O.P. NUMBERS. To avoid an enormous number of different L.O.P. numbers referring to the same thing, HH. will adopt a scheme whereby when an experimental modification is made to an item in an L.O.P., a sheet is issued which bears the L.O.P number plus the suffix "Ex" and another number. Both the L.O.P. number and the Ex. number appear in the specification. A small sheet bearing the L.O.P. and the Ex. number simply gives the information as to where the experimental modification differs from the original L.O.P. HH. will circulate prints of these small sheets to Ev.{Ivan Evernden - coachwork}, HPS{Horace Percy Smith - Experimental Factory Mgr}/RH{R. Hollingworth}, and Rm.{William Robotham - Chief Engineer} With regard to the form which the main Index Sheets for chassis or engines shall take, HH. is going to modify these to make it in line with the new requirements. He will also ensure that room is left to enable a verbal interpretation of L.O.P numbers to be incorporated at each stage of the unit's life. In order to enable RH.{R. Hollingworth} to inform those concerned as to the actual specification to which he has built a unit in the first place, HH. will supply him with 4 prints of his Index Sheet filled in as far as possible, and RH.{R. Hollingworth} will add his items to this sheet and then circulate it. | ||