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).
Comparing the weight of the J.3 unit to the standard 20/25 engine, noting a significant weight saving.
| Identifier | ExFiles\Box 107\4\ scan0116 | |
| Date | 20th February 1932 | |
| SECRET. X4538. To R.{Sir Henry Royce} From Hs.{Lord Ernest Hives - Chair} c. to Sg.{Arthur F. Sidgreaves - MD} Wor.{Arthur Wormald - General Works Manager} c. to E.{Mr Elliott - Chief Engineer} Da.{Bernard Day - Chassis Design} c. to BY.{R.W. Bailey - Chief Engineer} Hs.{Lord Ernest Hives - Chair}7/HJ.20.2.32. J.3 UNIT. X.5770. X.4538, A comparison of the weight of J.3 unit compared with the present standard 20/25 shows there to be a reduction in weight of approximately 81 lbs. This may have to be revised when the final analysis is made, but it is encouraging that although we have increased the capacity of the engine by over 25 %, there is going to be a very definite saving in weight. Hs.{Lord Ernest Hives - Chair} | ||