| Description | Date | Identifier | |
| The design and procedure for a rig to test the trunnions of a 40/50 steering box. | 19th Jan 1923 | West Wittering \ J \ January1923 Scan94 | |
| Design modifications to prevent a tube from splitting, including reinforcing an aluminium part with steel bolts. | 24th Jan 1928 | West Wittering \ J \ January1923 Scan95 | |
| Pencil sketch showing two views of a mechanical component. | 9th Feb 1926 | West Wittering \ J \ January1923 Scan96 | |
| Assessment of the S.Goshawk 11's performance, focusing on its silent operation and potential modifications. | 9th Jan 1923 | West Wittering \ J \ January1923 Scan97 | |
| Mr. Royce's preference for a dull finish on spanners. | 26th Jan 1923 | West Wittering \ J \ January1923 Scan98 | |
| Results from testing Delage springs and correcting the pitch angle of a worm helix. | 26th Jan 1923 | West Wittering \ J \ January1923 Scan99 | |
| Abandoning the 'Stork' and 'Heron' models and repurposing parts for the experimental 'Seagull' model. | 26th Jan 1923 | West Wittering \ J \ January1923 Scan100 | |
| The 'Seagull' cylinder block, head gasket, and alterations, explaining the design choice of casting it in two groups of three cylinders. | 27th Jan 1923 | West Wittering \ J \ January1923 Scan101 | |
| Requesting information and outlining tests on road springs, as per Mr. Royce's instructions. | 27th Jan 1923 | West Wittering \ J \ January1923 Scan102 | |
| Mr. Royce's comments on proposed alterations to an American chassis. | 26th Jan 1923 | West Wittering \ J \ January1923 Scan103 | |
| The change of material for pivot thrust washers from fiber to Genelite. | 27th Jan 1923 | West Wittering \ J \ January1923 Scan104 | |
| The 'Seagull' frame side members and associated drawings. | 27th Jan 1923 | West Wittering \ J \ January1923 Scan105 | |
| 40-mile road test of the '4. Goshawk' car, providing feedback on steering and carburation. | 29th Jan 1923 | West Wittering \ J \ January1923 Scan106 | |
| Page detailing suggestions for a car's throttle, tool bag, cutout, dashboard lights, dynamo, and paint. | 11th Aug 1920 | West Wittering \ J \ January1923 Scan107 | |
| Issues with a car's starter motor and ignition plugs, and arranging its transport to France. | 11th Aug 1920 | West Wittering \ J \ January1923 Scan108 | |
| Sending drawings for the Seagull dynamo and reducing its external carcase size. | 29th Jan 1923 | West Wittering \ J \ January1923 Scan109 | |
| Alterations and improvements to steering mechanisms, including the rejection of 'Jacob's gear'. | 29th Jan 1923 | West Wittering \ J \ January1923 Scan110 | |
| The correct procedure for drilling and bushing the holes in the top leaf of springs. | 31th Jan 1923 | West Wittering \ J \ January1923 Scan111 | |
| Use of case-hardened steel to prevent wear and the critical importance of spring alignment. | 29th Jan 1923 | West Wittering \ J \ January1923 Scan112 | |
| Technical policy regarding chassis reliability and repair strategy, contrasting with American and Ford models. | 29th Jan 1923 | West Wittering \ J \ January1923 Scan113 | |
| Car bodies for the Goshawk model, proposing a new design based on a successful Hooper open-tourer. | 29th Jan 1923 | West Wittering \ J \ January1923 Scan114 | |
| Passenger access, body dimensions for the Goshawk chassis, and the causes of 'booming' sounds in car bodies. | 29th Jan 1923 | West Wittering \ J \ January1923 Scan115 | |
| Suggesting modifications to the Goshawk Dynamo's field winding and control brush to improve output. | 29th Jan 1923 | West Wittering \ J \ January1923 Scan116 | |
| Design change to the Goshawk ignition coil to incorporate mouldensite insulation. | 29th Jan 1923 | West Wittering \ J \ January1923 Scan117 | |
| Prioritizing the 'Seagull' project, fearing delays from 'Stork' & 'Heron' chassis work, and noting concerns about front wheel brakes. | 31th Jan 1923 | West Wittering \ J \ January1923 Scan118 | |
| Reliability of the Bijur starter drive compared to the Bendix drive. | 1st Feb 1928 | West Wittering \ J \ January1923 Scan119 | |
| Agreeing to standardise a modification for the Goshawk ignition coils. | 31th Jan 1923 | West Wittering \ J \ January1923 Scan120 | |
| Maintenance and limitations of Goshawk 11 universal joints. | 31th Jan 1923 | West Wittering \ J \ January1923 Scan121 | |
| Telegram from Royce regarding engine alterations and an oil leak. | 31th Jan 1923 | West Wittering \ J \ January1923 Scan122 | |
| Wear tests and investigations into the co-efficient of friction for Ferodo clutch material on a Goshawk Clutch. | 1st Mar 1923 | West Wittering \ J \ March1923 Scan0 | |
| Experimental bench trial report for the Goshawk Dynamo. | 12th Mar 1923 | West Wittering \ J \ March1923 Scan1 | |
| Performance changes to a dynamo after modifications, comparing it to previous tests and specifications. | 1st Mar 1923 | West Wittering \ J \ March1923 Scan2 | |
| Graph comparing the output curves of Goshawk and U.S.A. Bosch dynamos. | 11th Jan 1933 | West Wittering \ J \ March1923 Scan3 | |
| Breather pipe arrangement from the crankcase to the hot air pipe. | 3rd Mar 1923 | West Wittering \ J \ March1923 Scan4 | |
| Design of a new miniature sparking plug from K.L.G. and requesting feedback on its dimensions. | 1st Mar 1923 | West Wittering \ J \ March1923 Scan5 | |
| Issue with Bosch spark plugs being too large for the cylinder head casting. | 7th Mar 1923 | West Wittering \ J \ March1923 Scan6 | |
| Methods tested to prevent oil leakage from the 40/50 HP universal joint. | 1st Mar 1923 | West Wittering \ J \ March1923 Scan7 | |
| Continued note on an improvement for oil retaining in the universal joint. | 1st Mar 1923 | West Wittering \ J \ March1923 Scan8 | |
| Tests to find a method for retaining oil on a 40/50 HP universal joint. | 1st Mar 1923 | West Wittering \ J \ March1923 Scan9 | |
| Improvement in oil retaining for a universal joint. | 9th Mar 1923 | West Wittering \ J \ March1923 Scan10 | |
| Proposed oil retainer scheme for a universal joint on a 40/50 chassis. | 9th Mar 1923 | West Wittering \ J \ March1923 Scan11 | |
| Query regarding a lock for the 20 HP spare wheel bolt, following reports of it working loose on the Goshawk model. | 3rd Mar 1923 | West Wittering \ J \ March1923 Scan12 | |
| Tests concerning the lubrication of the 40/50 model's clutch spigot. | 3rd Mar 1923 | West Wittering \ J \ March1923 Scan13 | |
| Suggestion to improve the lubrication method of the clutch by introducing a more reliable manual system. | 13th Mar 1923 | West Wittering \ J \ March1923 Scan14 | |
| The sending of an improved wooden model of a 40/50 steering wheel. | 13th Mar 1923 | West Wittering \ J \ March1923 Scan15 | |
| Test bench experiments comparing induction pipes and port arrangements on a Marmon engine against an E.A.C. engine, detailing a subsequent engine failure. | 15th Mar 1923 | West Wittering \ J \ March1923 Scan16 | |
| Engine tests comparing the B.M.E.P. of a Marmon engine to a Goshawk-11 and discussing valve timings. | 15th Mar 1923 | West Wittering \ J \ March1923 Scan17 | |
| Distribution experiments for a Marmon engine's intake manifold. | 15th Mar 1923 | West Wittering \ J \ March1923 Scan18 | |
| Non-homogenous fuel mixture supply in an intake manifold with sketches. | 1st Mar 1923 | West Wittering \ J \ March1923 Scan19 | |
| Performance graph of a Marmon engine from a bench test plotting various metrics against RPM. | 6th Mar 1923 | West Wittering \ J \ March1923 Scan20 | |
| Power curves for a Marmon 34 engine, showing the effect of different valve timing with a Stromberg carburetter. | 15th Mar 1923 | West Wittering \ J \ March1923 Scan21 | |
| Performance comparison graph of Stromberg and S.U. carburettors, plotting B.HP, fuel consumption, and depression against R.P.M. | 11th Mar 1923 | West Wittering \ J \ March1923 Scan22 | |
| Blueprint chart showing the inlet valve timing and displacement for a Marmon engine. | 7th May 1929 | West Wittering \ J \ March1923 Scan23 | |
| Valve displacement and exhaust timing diagram for a Marmon 6-cylinder engine. | 7th May 1929 | West Wittering \ J \ March1923 Scan24 | |
| Spring torsion and distortion tests, referencing two graphs and test number X2628. | 17th Mar 1923 | West Wittering \ J \ March1923 Scan25 | |
| Graph and diagram showing the results of a lateral distortion test on a 40/50 spring under load. | 15th Mar 1928 | West Wittering \ J \ March1923 Scan26 | |
| Diagram and graph detailing a torsion experiment on a spring. | 15th Mar 1928 | West Wittering \ J \ March1923 Scan27 | |
| Cover memo for the revised calculations of the X.9700 - E.A.C. Dynamo. | 20th Mar 1923 | West Wittering \ J \ March1923 Scan28 | |
| Revised calculations for an E.A.C. Dynamo. | 19th Mar 1923 | West Wittering \ J \ March1923 Scan29 | |
| Calculations for armature and field coil specifications, page 2. | 11th Jan 1933 | West Wittering \ J \ March1923 Scan30 | |
| Calculation table for the magnetic circuit of components like the armature, pole core, and yoke. | 11th Jan 1933 | West Wittering \ J \ March1923 Scan31 | |
| Page of calculations for wire coil windings, resistance, and ampere turns for a shunt machine. | 11th Jan 1933 | West Wittering \ J \ March1923 Scan32 | |
| List of principal quantities and calculations for an electrical shunt machine. | 26th Mar 1923 | West Wittering \ J \ March1923 Scan33 | |
| Response detailing failures of ignition contacts and dynamo brushes for 4-GII electrical equipment. | 26th Mar 1923 | West Wittering \ J \ March1923 Scan34 | |
| Dynamo testing, focusing on brush positioning to resolve sparking and heating issues. | 26th Mar 1923 | West Wittering \ J \ March1923 Scan35 | |
| Testing for mechanical wear and experiments with brushes and commutators. | 26th Mar 1923 | West Wittering \ J \ March1923 Scan36 | |
| Necessity of a support for the raked steering column on the 20 HP model. | 26th Mar 1923 | West Wittering \ J \ March1923 Scan37 | |
| American chassis alterations, awaiting a decision and noting a requested experiment on 40/50 engine gears. | 21th Jun 1928 | West Wittering \ J \ March1923 Scan38 | |
| From 'E' to 'C.J.' regarding a request for more information for Mr. Royce's decision on matters concerning the American Company. | 2nd Mar 1923 | West Wittering \ J \ March1923 Scan39 | |
| Status report on vehicle components, detailing actions required and comparisons to American models. | 3rd Mar 1923 | West Wittering \ J \ March1923 Scan40 | |
| Report discussing component changes and information requests for hand pumps, engine covers, brake stops, and water pump spindles. | 3rd Mar 1923 | West Wittering \ J \ March1923 Scan41 | |
| Discussions and required actions for gears, valves, axles, and magneto drives. | 3rd Mar 1923 | West Wittering \ J \ March1923 Scan42 | |
| Status report requesting further information on a magneto drive and axle bevel pinion for an American chassis. | 3rd Mar 1923 | West Wittering \ J \ March1923 Scan43 | |
| Secret memo regarding a test rig for a new method of fixing cheeses on a steering mechanism. | 3rd Mar 1923 | West Wittering \ J \ March1923 Scan44 | |
| Preferred design for a stay for a 40/50 swan neck pipe. | 3rd Mar 1923 | West Wittering \ J \ March1923 Scan45 | |
| Modifications to the Goshawk rear axle casing to prevent breakages. | 3rd Mar 1923 | West Wittering \ J \ March1923 Scan46 | |
| Goshawk 11 electrical equipment failures, with proposed solutions for the ignition, dynamo, and armature. | 7th Mar 1923 | West Wittering \ J \ March1923 Scan47 | |
| Requesting a signature on standardisation sheets to avoid delaying modification procedures. | 9th Mar 1923 | West Wittering \ J \ March1923 Scan48 | |
| Suggestions for the Goshawk 11 cutout operation. | 10th Mar 1923 | West Wittering \ J \ March1923 Scan49 | |
| Modifications to the Goshawk 11 front axle, steering, and suspension. | 14th Mar 1923 | West Wittering \ J \ March1923 Scan50 | |
| Experimental locking mechanisms for the Goshawk 11 wheel carrier, including a thief-proof option. | 14th Mar 1923 | West Wittering \ J \ March1923 Scan51 | |
| Alternative positive lock for the Goshawk II wheel carrier. | 16th Mar 1923 | West Wittering \ J \ March1923 Scan52 | |
| Objectionable clicking sound in the Watford Magneto Control for a Goshawk 11 engine. | 19th Mar 1923 | West Wittering \ J \ March1923 Scan53 | |
| Taller ignition coil for a Goshawk vehicle. | 19th Mar 1923 | West Wittering \ J \ March1923 Scan54 | |
| Design of Goshawk 11 Radius Rods and an accompanying scheme. | 20th Mar 1923 | West Wittering \ J \ March1923 Scan55 | |
| Provision and improvement of a Goshawk 11 all-weather head and body. | 1st Mar 1923 | West Wittering \ J \ March1923 Scan56 | |
| Steering column rigidity issues on the 20 HP model related to the instrument board bracket. | 23th Mar 1928 | West Wittering \ J \ March1923 Scan57 | |
| The Goshawk 11 front radius rod system, detailing modifications to springs, shackles, and brackets. | 23th Mar 1923 | West Wittering \ J \ March1923 Scan58 | |
| Change from aluminium to steel brackets for the Goshawk II chassis wiring. | 23th Mar 1923 | West Wittering \ J \ March1923 Scan59 | |
| Non-receipt of adapters for miniature sparking plugs. | 24th Mar 1923 | West Wittering \ J \ March1923 Scan60 | |
| Requirements for a lightweight, simple magneto for the Goshawk engine as a secondary ignition system. | 24th Mar 1923 | West Wittering \ J \ March1923 Scan61 | |
| Preferences for engine components such as magnetos, spark plugs, and ignition systems. | 27th Mar 1923 | West Wittering \ J \ March1923 Scan62 | |
| N.scheme 1394 for the 20.HP model, focusing on the side steering tube and alternative spring loads for the flexible joint. | 27th Mar 1923 | West Wittering \ J \ March1923 Scan63 | |
| Goshawk II front axle radius rods (X4263), detailing steering lock adjustments and bracket positioning for optimal geometry. | 28th Mar 1923 | West Wittering \ J \ March1923 Scan64 | |
| Letter from F.H. Royce regarding an upcoming visit, a request for tools, performance of a 20 HP car, and aero engine considerations. | 31th Mar 1923 | West Wittering \ J \ March1923 Scan65 | |
| Postscript discussing vehicle shackle noise and recommending specific English compound engine oils. | 19th Jul 1917 | West Wittering \ J \ March1923 Scan66 | |
| Design improvements for a petrol level indicator glass and washer assembly. | 1st May 1923 | West Wittering \ J \ May1923 Scan0 | |
| Letter from F. H. Royce discussing the unsuitability of the Goshawk/20.HP chassis for heavy bodies and its potential harm to the company's reputation. | 2nd May 1923 | West Wittering \ J \ May1923 Scan1 | |
| Proposal to create a standard set of drawings for an improved, universal pipe nipple design. | 3rd May 1923 | West Wittering \ J \ May1923 Scan2 | |
| Secret memo from E. to H.S. discussing the progress of an engine's development and parts. | 5th May 1923 | West Wittering \ J \ May1923 Scan3 | |
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