| Description | Date | Identifier | |
| Issues with chassis engine pistons, including skirt collapse and 'bucketing', and proposing improved designs. | 11th May 1933 | Box 86 \ 2 scan0030 | |
| Requesting the production of an experimental Bensport piston set for testing and outlining its design. | 15th May 1933 | Box 86 \ 2 scan0031 | |
| Authorising tests to delete the piston ring stops on Bentley engines. | 19th May 1933 | Box 86 \ 2 scan0032 | |
| Request to the Bentley Unit to make three sets of piston rings for V1597. | 6th Jul 1933 | Box 86 \ 2 scan0033 | |
| Analysis of gudgeon pin and piston sizes, comparing actual interference fits with drawing specifications for Bentley Pistons. | 24th Jul 1933 | Box 86 \ 2 scan0034 | |
| Piston failures and modifications during Bentley engine testing. | 22th Aug 1933 | Box 86 \ 2 scan0035 | |
| Piston failures after 6,300 miles and proposed modifications to prevent seizing. | 22th Aug 1933 | Box 86 \ 2 scan0036 | |
| Blueprint diagram of a piston. | 18th Aug 1933 | Box 86 \ 2 scan0037 | |
| Blueprint diagram of No. 5 piston noting that the top two rings on all pistons were found jammed. | 18th Aug 1933 | Box 86 \ 2 scan0038 | |
| Blueprint comparing three different Bentley piston designs with dimensions and test results. | 22th Aug 1933 | Box 86 \ 2 scan0039 | |
| Request to manufacture two sets of Bensport pistons with a specific modification for endurance tests. | 23th Aug 1933 | Box 86 \ 2 scan0040 | |
| Design and development of a Bentley piston. | 24th Aug 1933 | Box 86 \ 2 scan0041 | |
| Loss of 3HP at top speeds due to the longer cylinder barrel used for Bentley Pistons. | 25th Aug 1933 | Box 86 \ 2 scan0042 | |
| Clarifying a misunderstanding regarding the dimensions on the Bentley piston. | 25th Aug 1933 | Box 86 \ 2 scan0043 | |
| Ordering a hold on Bentley piston production due to failures and outlining the subsequent investigation. | 25th Aug 1933 | Box 86 \ 2 scan0044 | |
| Letter to The Automotive Engineering Co. Ltd. regarding piston failures with RR.53 alloy. | 25th Aug 1933 | Box 86 \ 2 scan0045 | |
| Recent failure of Bentley pistons, its potential causes, and next steps for development. | 26th Aug 1933 | Box 86 \ 2 scan0046 | |
| Letter from The Automotive Engineering Co Ltd regarding R.R.53 alloy and piston development. | 26th Aug 1933 | Box 86 \ 2 scan0047 | |
| Piston and crankshaft failures during a high-speed endurance test on a Bentley Unit C.13 engine. | 26th Aug 1933 | Box 86 \ 2 scan0048 | |
| The failure of a No.6 balance weight on the No.4 journal, which broke through the crankcase. | 8th Aug 1933 | Box 86 \ 2 scan0049 | |
| Blueprint diagram illustrating a crack failure on a Bentley piston, including a table of dimensional data. | 29th Aug 1933 | Box 86 \ 2 scan0050 | |
| Development and design decisions for Bentley pistons, specifically regarding skirt and land dimensions. | 28th Aug 1933 | Box 86 \ 2 scan0051 | |
| Improved heat treatment for Bentley pistons and requesting an order for new die castings. | 29th Aug 1933 | Box 86 \ 2 scan0052 | |
| Blueprint detailing the grinding specifications and dimensions for two 'Bensport' pistons. | 29th Aug 1933 | Box 86 \ 2 scan0053 | |
| Inquiry to The Light Production Co. Ltd. regarding the availability of 'Aerolite' pistons for a Bentley chassis. | 24th Aug 1933 | Box 86 \ 2 scan0054 | |
| Letter from The Light Production Co. Ltd. regarding the use of Aerolite Pistons and proposing a meeting. | 28th Aug 1933 | Box 86 \ 2 scan0055 | |
| Letter to The Light Production Co. confirming a visit and sending drawings for Aerolite pistons to be tried in a Bentley chassis. | 1st Sep 1933 | Box 86 \ 2 scan0056 | |
| Letter from The Light Production Co. Ltd. discussing piston drawings and requesting material specifications. | 4th Sep 1933 | Box 86 \ 2 scan0057 | |
| Page 2 of a letter from The Light Production Co. Ltd. quoting a price and lead time for twelve pistons. | 6th Sep 1933 | Box 86 \ 2 scan0058 | |
| Letter to The Light Production Co. Ltd. regarding a piston drawing, material specifications, and an order for twelve pistons. | 6th Sep 1933 | Box 86 \ 2 scan0059 | |
| Request to order 12 Aerolite pistons for testing in a Bentley from the Light Production Co. Ltd. | 6th Sep 1933 | Box 86 \ 2 scan0060 | |
| Requesting the production of a modified set of pistons for the C.XI unit to improve bedding and prevent failure. | 7th Sep 1933 | Box 86 \ 2 scan0061 | |
| Suggested dimensions for a further set of experimental 3½ Litre Bentley pistons. | 7th Sep 1933 | Box 86 \ 2 scan0062 | |
| Blueprint detailing modifications for grinding an EB.500 piston to EB.495 specifications. | 7th Sep 1933 | Box 86 \ 2 scan0063 | |
| Reproduction of Bentley piston failures on a test bed and proposed solutions. | 8th Sep 1933 | Box 86 \ 2 scan0064 | |
| Design and testing of unsplit Bentley pistons. | 15th Sep 1933 | Box 86 \ 2 scan0065 | |
| The results of endurance testing on pistons for two different engine units. | 21th Sep 1933 | Box 86 \ 2 scan0066 | |
| Design and testing of various Bentley piston types. | 23th Sep 1933 | Box 86 \ 2 scan0067 | |
| High-speed endurance test on pistons, detailing a valve failure and subsequent inspection. | 23th Sep 1933 | Box 86 \ 2 scan0068 | |
| Requesting experiments to change the gudgeon pin from an interference fit to a push fit. | 26th Sep 1933 | Box 86 \ 2 scan0069 | |
| Letter from The Light Production Co. Ltd. regarding a delay in the manufacture of experimental Aerolite Pistons. | 26th Sep 1933 | Box 86 \ 2 scan0070 | |
| Request to produce two more sets of semi-split skirt pistons for the Bentley. | 27th Sep 1933 | Box 86 \ 2 scan0071 | |
| Confirming the production of two sets of gudgeon pins with no interference fit. | 27th Sep 1933 | Box 86 \ 2 scan0072 | |
| Letter from The Light Production Co. Ltd. regarding a delay in producing experimental Aerolite Pistons due to foundry defects. | 4th Oct 1933 | Box 86 \ 2 scan0073 | |
| Page 2 of a letter from The Light Production Co. Ltd. regarding casting defects and delays with pistons. | 10th Oct 1933 | Box 86 \ 2 scan0074 | |
| Modifications to the Bentley Semi-Split Piston to prevent seizing, due to oil shortage and incorrect clearance. | 10th Oct 1933 | Box 86 \ 2 scan0075 | |
| Modifications to the Bentley Semi-Split Piston to address a seizing issue. | 10th Oct 1933 | Box 86 \ 2 scan0076 | |
| Letter to The Light Production Co. Ltd. regarding the increased weight of supplied pistons for a Bentley engine. | 17th Oct 1933 | Box 86 \ 2 scan0077 | |
| Letter regarding the dispatch of twelve Aerolite experimental pistons for testing in a Bentley engine. | 17th Oct 1933 | Box 86 \ 2 scan0078 | |
| Page 2 of a letter from The Light Production Co. Ltd. regarding gudgeon pin fit. | 18th Oct 1933 | Box 86 \ 2 scan0079 | |
| Report investigating trouble with piston knocks on Bentley engine units. | 18th Oct 1933 | Box 86 \ 2 scan0080 | |
| Piston testing, comparing different heat treatments, dimensions, and grinding specifications to diagnose engine knocking. | 18th Oct 1933 | Box 86 \ 2 scan0081 | |
| Future testing procedures for pistons, including hardness checks at various points. | 18th Oct 1933 | Box 86 \ 2 scan0082 | |
| 24-hour endurance test for Bentley piston development, detailing a piston seizure and planned modifications. | 18th Oct 1933 | Box 86 \ 2 scan0083 | |
| Confirming arrangements to test Bentley Trials cars for deterioration and requesting information on detecting piston failure. | 18th Oct 1933 | Box 86 \ 2 scan0084 | |
| Letter from The Light Production Co. Ltd. concerning the weight and design of Bentley pistons. | 19th Oct 1933 | Box 86 \ 2 scan0085 | |
| Letter from The Light Production Co. Ltd. discussing experiments with smaller bores. | 20th Oct 1935 | Box 86 \ 2 scan0086 | |
| Piston failure in a 3 1/2 Litre Bentley and the potential need for a radical design change. | 20th Oct 1935 | Box 86 \ 2 scan0087 | |
| The diagnosis and procedure for piston trouble and knock. | 20th Oct 1933 | Box 86 \ 2 scan0088 | |
| Letter to The Light Production Co. Ltd. regarding a seized Aerolite piston during a test bed run. | 21th Oct 1933 | Box 86 \ 2 scan0089 | |
| Telegram confirming a visit for the following day at 2:30 PM. | 23th Oct 1933 | Box 86 \ 2 scan0090 | |
| The performance of gudgeon pins with a sliding fit in Aerolite pistons. | 24th Oct 1933 | Box 86 \ 2 scan0091 | |
| Letter from the Experimental Department regarding the despatch and examination of pistons. | 25th Oct 1933 | Box 86 \ 2 scan0092 | |
| Page two of a letter to Light Production Co. with a handwritten note regarding scrapped pistons. | 25th Oct 1933 | Box 86 \ 2 scan0093 | |
| The despatch of failed Aerolite pistons and gudgeon pins for examination to the Light Production Co. Ltd. | 25th Oct 1933 | Box 86 \ 2 scan0094 | |
| Urgent internal memo regarding the replacement of cracked Aerolite pistons and gudgeon pins. | 25th Oct 1933 | Box 86 \ 2 scan0095 | |
| Sending drawing LeC.3675 for a strengthened Bentley piston. | 25th Oct 1933 | Box 86 \ 2 scan0096 | |
| Investigation into failures on Bentley pistons and proposing a modification. | 25th Oct 1933 | Box 86 \ 2 scan0097 | |
| Endurance test report for Aerolite pistons on a Bentley No. 7 unit. | 25th Oct 1933 | Box 86 \ 2 scan0098 | |
| Piston endurance testing, detailing failures, inspections, and subsequent modifications. | 25th Oct 1933 | Box 86 \ 2 scan0099 | |
| Engine endurance testing, detailing piston seizure, cracking, and oil temperature trials. | 25th Oct 1933 | Box 86 \ 2 scan0100 | |
| Engine endurance run detailing oil consumption, a crankcase crack, and S.U. carburetter washer failure. | 25th Oct 1933 | Box 86 \ 2 scan0101 | |
| Sketch showing how a gudgeon pin forced an Aerolite (Bentley) piston to one side of the bore. | 25th Oct 1933 | Box 86 \ 2 scan0102 | |
| Sketch showing a crack in an Aerolite piston. | 5th May 1939 | Box 86 \ 2 scan0103 | |
| Sketch showing a crack in the crankcase of a B.7 unit after 17 hours of operation. | 23th Oct 1933 | Box 86 \ 2 scan0104 | |
| Performance graph showing B.H.P and B.M.E.P. against R.P.M. for a Bentley No. 7 Unit with Aerolite pistons after an endurance test. | 23th Oct 1933 | Box 86 \ 2 scan0105 | |
| Blueprint detailing the dimensions of Aerolite pistons before and after modification. | 26th Oct 1933 | Box 86 \ 2 scan0106 | |
| Failures of gudgeon pins and pistons due to interference fit and proposing alternative solutions. | 25th Oct 1933 | Box 86 \ 2 scan0107 | |
| 3 1/4 litre Bentley Piston Failure, its cause, and proposed solutions. | 26th Oct 1933 | Box 86 \ 2 scan0108 | |
| 3 1/2 litre Bentley piston failures and subsequent testing at Brooklands. | 26th Oct 1933 | Box 86 \ 2 scan0109 | |
| Confirming the use of the standard piston treatment for the Bentley chassis, as a new treatment has not been successfully tested. | 26th Oct 1933 | Box 86 \ 2 scan0110 | |
| Type of piston with an improved gudgeon pin boss to be used for tests at Brooklands. | 26th Oct 1933 | Box 86 \ 2 scan0111 | |
| Letter from The Light Production Co. Ltd. regarding the receipt of pistons, gudgeon pins, and a blueprint, and the despatch of standard channel scraper rings. | 26th Oct 1933 | Box 86 \ 2 scan0112 | |
| Letter from The Light Production Co. Ltd. regarding alterations to casting equipment to achieve weight savings. | 26th Oct 1933 | Box 86 \ 2 scan0113 | |
| The material selection for gudgeon pins without interference fit for aero engines. | 26th Oct 1933 | Box 86 \ 2 scan0114 | |
| Agreement for a limited production run of Bentley Pistons to the latest design. | 26th Oct 1933 | Box 86 \ 2 scan0115 | |
| Calculating the loads and pressures related to a Bentley piston failure. | 27th Oct 1933 | Box 86 \ 2 scan0116 | |
| Expressing pleasure that the cause of 3 1/2-litre Bentley piston failures has been identified. | 27th Oct 1933 | Box 86 \ 2 scan0117 | |
| Investigating a 3½ Litre Bentley engine failure, concluding it was caused by an exhaust valve, not the piston. | 28th Oct 1933 | Box 86 \ 2 scan0118 | |
| Instruction to revert to the original heat treatment for pistons following a failure analysis at Brooklands. | 31th Oct 1933 | Box 86 \ 2 scan0119 | |
| Letter from The Light Production Co. Ltd. discussing the contour of a piston after an endurance test. | 31th Oct 1933 | Box 86 \ 2 scan0120 | |
| Letter from The Light Production Co. Ltd. discussing piston adjustments, grinding, and potential issues like cold taps. | 31th Oct 1933 | Box 86 \ 2 scan0121 | |
| Graph showing pressure face diameter reductions given by different standard cam forms. | 1st Nov 1933 | Box 86 \ 2 scan0122 | |
| Letter from the Experimental Department regarding Aerolite pistons and the RR.53 alloy. | 1st Nov 1933 | Box 86 \ 2 scan0123 | |
| Drawings for an experimental forged aluminium connecting rod and a piston for a Bentley. | 1st Nov 1933 | Box 86 \ 2 scan0124 | |
| Receipt, modification, and testing of Aerolite pistons. | 2nd Nov 1933 | Box 86 \ 2 scan0125 | |
| Cover note for a record of running times for Duralumin connecting rods and strengthened pistons sent for inspection. | 2nd Nov 1933 | Box 86 \ 2 scan0126 | |
| Endurance test results for duralumin connecting rods and strengthened pistons. | 11th Nov 1933 | Box 86 \ 2 scan0127 | |
| Charts showing dimensions and average weights of a second batch of Aerolite pistons compared to Bentley Pistons. | 11th Nov 1933 | Box 86 \ 2 scan0128 | |
| Table of dimensions for Aero-Lite Pistons from the 2nd delivery, with accompanying diagrams. | 2nd Nov 1933 | Box 86 \ 2 scan0129 | |
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