| Description | Date | Identifier | |
| Issues with non-standard tyres, inconsistent tappet oiling, and high oil temperatures. | 9th Apr 1934 | Box 11 \ 5 05-page025 | |
| Acceleration test figures for vehicle 28-EX, including 3rd speed data and test conditions. | 13th Apr 1934 | Box 11 \ 5 05-page026 | |
| Diagnosing a petrol supply failure by monitoring under-bonnet and atmospheric temperatures. | 13th Apr 1934 | Box 11 \ 5 05-page027 | |
| 5,000-mile report on vehicle 28-EX. | 14th Apr 1934 | Box 11 \ 5 05-page028 | |
| 8000-mile report on Engine Unit PH.11. NO.28, detailing performance issues and findings after dismantling. | 10th Apr 1934 | Box 11 \ 5 05-page029 | |
| The performance and issues of various engine and drivetrain components. | 10th Apr 1934 | Box 11 \ 5 05-page030 | |
| Observations and modifications on various components including the carburetter, petrol tank, pedals, radiator, and camshaft. | 10th Apr 1934 | Box 11 \ 5 05-page031 | |
| The performance and issues of various vehicle components including an engine coupling, propeller shaft, hydraulic dampers, and steering column. | 10th Apr 1934 | Box 11 \ 5 05-page032 | |
| The condition and performance of various vehicle components, including pivots, brakes, axle, and electrical systems. | 10th Apr 1934 | Box 11 \ 5 05-page033 | |
| Faults with the starter motor, bodywork, and noting vehicle specifications and tyre wear. | 14th Apr 1934 | Box 11 \ 5 05-page034 | |
| Letter to J. Bowering regarding the treatment of parts with Alum. Hydroxide and the petrol system of a Streamlined Car. | 14th Apr 1934 | Box 11 \ 5 05-page035 | |
| Requesting clarification on the new features being tested on experimental car 28-EX. | 9th Apr 1934 | Box 11 \ 5 05-page036 | |
| Specific parts fitted to model 28-EX, including modifications to the valve stems and water pump. | 14th Apr 1934 | Box 11 \ 5 05-page037 | |
| Letter to G.W. Hancock regarding the fouling of universal joints and a proposed spring modification. | 14th Apr 1934 | Box 11 \ 5 05-page038 | |
| The investigation and attempted improvements for noisy silent tappets. | 14th Apr 1934 | Box 11 \ 5 05-page039 | |
| Letter on hotel stationery proposing a modification to a petrol pump and filter unit to improve petrol feed. | 14th Apr 1934 | Box 11 \ 5 05-page040 | |
| Hand-drawn sketch of a filter mechanism with annotations on hotel letterhead. | 15th Apr 1934 | Box 11 \ 5 05-page041 | |
| Report comparing the 28-EX car with the 25-EX, detailing performance issues and modifications to the gearbox and tappets. | 15th Apr 1934 | Box 11 \ 5 05-page042 | |
| Technical memo reporting on the standardisation of parts for the 28-EX model after testing. | 14th Apr 1934 | Box 11 \ 5 05-page043 | |
| Issues with valve springs, petrol, and a list of ongoing maintenance tasks on a vehicle. | 17th Apr 1934 | Box 11 \ 5 05-page044 | |
| Note from Hancock detailing failures with a silencer mounting, requiring stronger springs and a redesigned bracket. | 17th Apr 1934 | Box 11 \ 5 05-page045 | |
| To G.W. Hancock in France discussing component standardisation, testing, and responsibility for issues. | 17th Apr 1934 | Box 11 \ 5 05-page046 | |
| Issues with electrical petrol pumps and the need for on-road testing to resolve them. | 17th Apr 1934 | Box 11 \ 5 05-page047 | |
| Letter to G.W. Hancock regarding tests on a 22-EX rear universal joint complaint. | 17th Apr 1934 | Box 11 \ 5 05-page048 | |
| Telegraph reporting the failure of three conrod oil pipes and that replacements have been sent for from Paris. | 10th Apr 1924 | Box 11 \ 5 05-page049 | |
| 5000-mile report on engine unit PH.II. NO.28, detailing performance issues and component failures. | 10th Apr 1934 | Box 11 \ 5 05-page050 | |
| Performance issues and observations on various vehicle components including tappets, clutch, servo, gearbox, and carburettor. | 10th Apr 1934 | Box 11 \ 5 05-page051 | |
| Modifications and performance of various engine and chassis components. | 10th Apr 1934 | Box 11 \ 5 05-page052 | |
| The performance and issues of a fabric coupling, universal joint, hydraulic dampers, and steering column. | 10th Apr 1934 | Box 11 \ 5 05-page053 | |
| The performance of steering, brakes, rear axle, and electrical systems. | 10th Apr 1934 | Box 11 \ 5 05-page054 | |
| Faults with the starter motor, electrics, and bodywork, along with vehicle specifications. | 12th Apr 1934 | Box 11 \ 5 05-page055 | |
| Letter addressing multiple vehicle issues including engine disintegration, tyre delivery, and oil leaks. | 12th Apr 1934 | Box 11 \ 5 05-page056 | |
| Letter from Chateauroux requesting to return to the Derby works after a 10,000 mile test. | 15th Apr 1934 | Box 11 \ 5 05-page057 | |
| Correcting a previously stated temperature location from scuttle to under bonnet. | 15th Apr 1934 | Box 11 \ 5 05-page058 | |
| Car repairs, detailing issues with auto adjustment plungers and problematic petrol pumps. | 16th Apr 1934 | Box 11 \ 5 05-page059 | |
| Requesting the urgent despatch of brake parts for a chassis undergoing a 10,000-mile trial in France. | 16th Apr 1934 | Box 11 \ 5 05-page060 | |
| Steering alterations and an investigation into high oil temperatures, including test data. | 17th Apr 1934 | Box 11 \ 5 05-page061 | |
| Engine temperature readings with notes on auto tappets, piston friction, and cylinder lubrication. | 17th Apr 1934 | Box 11 \ 5 05-page062 | |
| Drawing of the front and rear ends of a side steering tube with dimensions. | 17th Apr 1934 | Box 11 \ 5 05-page063 | |
| Graph comparing various engine temperature readings with radiator shutters operating normally versus held open. | 17th Apr 1934 | Box 11 \ 5 05-page064 | |
| Results of tests concerning high oil temperatures. | 18th Apr 1934 | Box 11 \ 5 05-page065 | |
| Letter discussing that the Harrison matrix is over-cooled based on temperature figures, and a query about steering friction. | 19th Apr 1934 | Box 11 \ 5 05-page066 | |
| Reporting the results of a road test concerning lengthened spring pads. | 19th Apr 1934 | Box 11 \ 5 05-page067 | |
| Report from France on road tests covering braking, clutch, exhaust, and fuel supply issues. | 19th Apr 1934 | Box 11 \ 5 05-page068 | |
| Petrol pump positioning and vapourisation, comparing Bentley and Phantom models with competitors. | 20th Apr 1934 | Box 11 \ 5 05-page069 | |
| Proposing a list of items for the T.2 series, and discussing production hold-ups for the fan and exhaust system. | 20th Apr 1934 | Box 11 \ 5 05-page070 | |
| Development issues including the petrol tank, luggage grid, and various component failures. | 20th Apr 1934 | Box 11 \ 5 05-page071 | |
| Letter on hotel stationery discussing problems with a car's petrol system. | 20th Apr 1934 | Box 11 \ 5 05-page072 | |
| Letter detailing attempts to resolve a petrol vaporising issue in a vehicle. | 21th Apr 1934 | Box 11 \ 5 05-page073 | |
| From G.W.H. to Hs. detailing a delay in completing the ten-thousand-mile test for car 28-EX due to required alterations. | 21th Apr 1934 | Box 11 \ 5 05-page074 | |
| From G.W.H. discussing radiator performance, steering adjustments, and test car decisions. | 21th Apr 1934 | Box 11 \ 5 05-page075 | |
| Test results and modifications for the Ph.II Rear Universal Joint. | 21th Apr 1934 | Box 11 \ 5 05-page076 | |
| Tests on a propeller shaft with an accompanying blueprint sketch. | 18th Apr 1934 | Box 11 \ 5 05-page077 | |
| Data table showing the results of propeller shaft tests conducted while driving over a humped-back bridge. | 18th Apr 1934 | Box 11 \ 5 05-page078 | |
| Road tests investigating propeller shaft coupling fouling issues. | 23th Apr 1934 | Box 11 \ 5 05-page079 | |
| Typed memo from G.W.H. in France requesting money to pay a hotel bill and send men home. | 23th Apr 1934 | Box 11 \ 5 05-page080 | |
| Sketch illustrating the fouling positions of a knuckle joint. | 23th Apr 1934 | Box 11 \ 5 05-page081 | |
| Temperature test results for a 28-EX model with bonnet and front flaps closed, with temperatures measured in degrees centigrade. | 23th Apr 1934 | Box 11 \ 5 05-page082 | |
| Temperature readings recorded at one-mile intervals with the bonnet closed and front flaps open. | 23th Apr 1934 | Box 11 \ 5 05-page083 | |
| Temperature readings in Centigrade taken at one-mile intervals with the rear of the bonnet wedged open. | 23th Apr 1939 | Box 11 \ 5 05-page084 | |
| Graph comparing engine temperature tests with radiator shutters working versus held open. | 23th Apr 1939 | Box 11 \ 5 05-page085 | |
| Technical issues and plans for a Bentley car, covering brake adjustments, the fan, luggage grid, and petrol pumps. | 30th Mar 1934 | Box 11 \ 5 05-page086 | |
| Diagnosing and attempting to repair fuel pump failures on a vehicle. | 30th Mar 1934 | Box 11 \ 5 05-page087 | |
| Pencil sketch of two views of a mechanical joint with handwritten annotations. | 30th Mar 1934 | Box 11 \ 5 05-page088 | |
| Schematic drawing illustrating chassis angles at the front and rear. | 23th Apr 1934 | Box 11 \ 5 05-page089 | |
| Bonnet ventilation and temperature tests following a 10,000-mile run, with recommendations for radiator matrix design. | 23th Apr 1934 | Box 11 \ 5 05-page090 | |
| Chassis 36-BX at 10,000 miles, detailing engine performance and acceleration figures. | 23th Apr 1934 | Box 11 \ 5 05-page091 | |
| Inspection report detailing the condition of a wheelcase, ignition plugs, petrol tank, engine coupling, and universal joints. | 23th Apr 1934 | Box 11 \ 5 05-page092 | |
| 10,000-mile report on chassis 26-EX, detailing engine performance and acceleration data. | 23th Apr 1934 | Box 11 \ 5 05-page093 | |
| Inspection report on the condition of engine components including connecting rods, pistons, cylinders, and valves. | 23th Apr 1934 | Box 11 \ 5 05-page094 | |
| Technical report on the status of various vehicle components including the clutch, servo motor, gearbox, and carburettor. | 23th Apr 1934 | Box 11 \ 5 05-page095 | |
| The performance and modifications of various vehicle components including dampers, radiator, and exhaust. | 23th Apr 1934 | Box 11 \ 5 05-page096 | |
| The condition of a wheelcase, ignition plugs, petrol tank, engine coupling, and universal joints. | 23th Apr 1934 | Box 11 \ 5 05-page097 | |
| Technical report on the performance of hydraulic dampers, steering, and the rear axle. | 11th Dec 1925 | Box 11 \ 5 05-page098 | |
| The performance and wear of steering tubes, buffer clearances, and brakes over a mileage test. | 11th Dec 1925 | Box 11 \ 5 05-page099 | |
| The condition of various electrical system components after a mileage test. | 11th Dec 1925 | Box 11 \ 5 05-page100 | |
| Faults with the headlamps, windscreen wiper motor, bodywork, and rear number plate illuminated unit. | 11th Dec 1925 | Box 11 \ 5 05-page101 | |
| Vehicle test report detailing faults, performance metrics, and tyre wear. | 18th Apr 1934 | Box 11 \ 5 05-page102 | |
| From G.W.H. regarding the exchange of cars, credit, and mileage while in France. | 18th Apr 1934 | Box 11 \ 5 05-page103 | |
| Requesting a list of items not yet cleared for production for car 28-EX, following a 5,000-mile running report. | 19th Apr 1934 | Box 11 \ 5 05-page104 | |
| Listing the serial numbers for six Dunlop tyre covers received. | 27th Apr 1934 | Box 11 \ 5 05-page105 | |
| Log of vehicle component measurements and adjustments at various mileage intervals. | 30th Mar 1934 | Box 11 \ 5 05-page106 | |
| Log tracking daily and cumulative petrol and oil consumption. | 28th Mar 1934 | Box 11 \ 5 05-page107 | |
| Graph plotting oil, water, and air temperatures against mileage during a 10,000-mile road test in France. | 20th Apr 1934 | Box 11 \ 5 05-page108 | |
| Graphical log from a 10,000-mile road test in France, tracking temperatures, speed, and fuel consumption. | 13th Apr 1934 | Box 11 \ 5 05-page109 | |
| Performance graph tracking oil, water, and air temperatures during a 10,000-mile test in France. | 6th Apr 1934 | Box 11 \ 5 05-page110 | |
| Performance graph tracking temperature and mileage during a 10,000-mile test in France. | 3rd Apr 1934 | Box 11 \ 5 05-page111 | |
| Performance graph logging data from the 10,000-mile test of the 28EX vehicle in France. | 28th Mar 1934 | Box 11 \ 5 05-page112 | |
| Measurements log for pivot lean and pivot load. | 30th Mar 1934 | Box 11 \ 5 05-page113 | |
| 10,000-mile report on car 28-EX, detailing the performance of engine unit P.II. No.28 and its acceleration figures. | 23th Apr 1934 | Box 11 \ 5 05-page114 | |
| Inspection report detailing the condition of engine components including connecting rods, pistons, cylinders, and valves. | 23th Apr 1934 | Box 11 \ 5 05-page115 | |
| Leaking soldered joint caused by a fouled coupling, with plans to fit longer plates. | 23th Apr 1934 | Box 11 \ 5 05-page116 | |
| The performance and condition of the clutch, servo motor, gearbox, carburettor, and air silencer. | 23th Apr 1934 | Box 11 \ 5 05-page117 | |
| The performance of various components including hydraulic dampers, pedals, radiator, exhaust manifold, carburettor, and camshaft. | 23th Apr 1934 | Box 11 \ 5 05-page118 | |
| The condition and testing of various vehicle components including the wheelcase, ignition plugs, petrol tank, and universal joints. | 23th Apr 1934 | Box 11 \ 5 05-page119 | |
| The performance of hydraulic dampers, steering column, and rear axle. | 23th Apr 1934 | Box 11 \ 5 05-page120 | |
| The performance and necessary modifications for the exhaust system, brake equaliser shafts, and road springs. | 11th Dec 1932 | Box 11 \ 5 05-page121 | |
| Performance and wear of steering, buffer, and braking systems over a mileage test. | 11th Dec 1932 | Box 11 \ 5 05-page122 | |
| Condition report on the vehicle's electrical system components after a mileage test. | 11th Dec 1932 | Box 11 \ 5 05-page123 | |
| Faults with the headlamps, windscreen wiper, bodywork, and rear number plate illuminated unit. | 11th Dec 1932 | Box 11 \ 5 05-page124 | |
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