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).
Test report detailing the wear measurements of six Aerolite raised crown pistons after a 15,000-mile test.
| Identifier | ExFiles\Box 97\4\ scan0201 | |
| Date | 24th November 1938 guessed | |
| UNIT N° B.111 N°.5 PISTON PROFILES PASSED TO TEST COMPLETED TEST RUNNING TIME MILEAGE 15,000 PISTONS AEROLITE RAISED CROWN IDENTIFICATION N° T2 RELIEVED SECTION BEDDING SECTION PISTON N° | RELIEVED SECTION | BEDDING SECTION --- | --- | --- | BEFORE | AFTER | WEAR | BEFORE | AFTER | WEAR 1 A-A | 3.4810 | 3.4813 | +.0003 | 3.4810 | 3.4813 | +.0003 B-B | 3.4808 | 3.4815 | +.0007 | 3.4805 | 3.4809 | +.0004 C-C | 3.4808 | 3.4816 | +.0008 | 3.4803 | 3.4807 | +.0004 D-D | 3.4820 | 3.4824 | +.0004 | 3.4361 | 3.4355 | -.0006 E-E | 3.4861 | 3.4870 | +.0009 | 3.5008 | 3.4986 | -.0022 2 A-A | 3.48125 | 3.4812 | -.00005 | 3.4812 | 3.4820 | +.0008 B-B | 3.4810 | 3.4813 | +.0003 | 3.4809 | 3.4812 | +.0003 C-C | 3.4809 | 3.4818 | +.0009 | 3.4807 | 3.4811 | +.0004 D-D | 3.4815 | 3.4818 | +.0003 | 3.4360 | 3.4350 | -.0001 E-E | 3.4863 | 3.4864 | +.0001 | 3.5005 | 3.4992 | -.0013 3 A-A | 3.4808 | 3.4818 | +.0010 | 3.4810 | 3.4819 | +.0009 B-B | 3.4805 | 3.4812 | +.0007 | 3.4807 | 3.4811 | +.0004 C-C | 3.4804 | 3.4810 | +.0006 | 3.4807 | 3.4807 | NIL. D-D | 3.4820 | 3.4822 | +.0002 | 3.4361 | 3.4351 | -.0010 E-E | 3.48775 | 3.4874 | -.00035 | 3.5008 | 3.4967 | -.0041 4 A-A | 3.4808 | 3.4815 | +.0007 | 3.4808 | 3.4819 | +.0011 B-B | 3.4808 | 3.4812 | +.0004 | 3.4805 | 3.4810 | +.0005 C-C | 3.4808 | 3.4812 | +.0004 | 3.4803 | 3.4804 | +.0001 D-D | 3.4818 | 3.4819 | +.0001 | 3.4353 | 3.4350 | -.0003 E-E | 3.4880 | 3.4870 | -.0010 | 3.4999 | 3.4986 | -.0013 5 A-A | 3.4811 | 3.4817 | +.0006 | 3.4812 | 3.4820 | +.0008 B-B | 3.4808 | 3.4817 | +.0009 | 3.48075 | 3.4810 | +.00025 C-C | 3.4803 | 3.4817 | +.0014 | 3.4807 | 3.4807 | NIL. D-D | 3.4819 | 3.4819 | NIL | 3.4362 | 3.4352 | -.0010 E-E | 3.4872 | 3.4865 | -.0007 | 3.5006 | 3.4987 | -.0019 6 A-A | 3.48075 | | | 3.4810 | | B-B | 3.48075 | | | 3.4805 | | C-C | 3.48075 | THIS PISTON SEIZED | | 3.4803 | THIS PISTON SEIZED | D-D | 3.4815 | | | 3.4360 | | E-E | 3.4863 | | | 3.5005 | | | ||