| Description | Date | Identifier | |
| Photograph illustrating damage to a 2nd motion shaft, with fractures on the gear retaining piece and a broken bolt. | 24th May 1932 | Box 15 \ 5 Scan305 | |
| Photograph showing a fractured 2nd motion shaft continuous gear and a broken outer ball race from a 1st motion shaft. | 27th May 1932 | Box 15 \ 5 Scan306 | |
| Alteration to the Phantom II 1st Speed Pinion. | 27th May 1932 | Box 15 \ 5 Scan307 | |
| New design to overcome two faults in the Phantom II and 20-HP Synchromesh. | 27th May 1932 | Box 15 \ 5 Scan308 | |
| Design alternatives for the S.M. Gearbox clamping mechanism and Woodruff key. | 30th May 1932 | Box 15 \ 5 Scan309 | |
| Gearbox sideshaft failure and proposing design improvements to strengthen the part. | 30th May 1932 | Box 15 \ 5 Scan310 | |
| On methods for preventing 'creeping gears' on splined shafts within gearboxes. | 30th May 1932 | Box 15 \ 5 Scan311 | |
| Testing, dangers, and solutions related to synchronous mesh gear creep. | 11th May 1932 | Box 15 \ 5 Scan312 | |
| Broken gear, the cause being an excessive helical angle, and clarifying design department procedures. | 11th May 1932 | Box 15 \ 5 Scan313 | |
| L.H. Phantom II Gearbox sideshaft failure, clarifying the part was non-standard. | 1st Jun 1932 | Box 15 \ 5 Scan314 | |
| Non-standard gear failure in an L.H. Phantom II gearbox and spiral angle specifications. | 2nd Jun 1932 | Box 15 \ 5 Scan315 | |
| Investigation and test results for lever fixing on a shaft, specifically concerning slip load. | 3rd Jun 1932 | Box 15 \ 5 Scan316 | |
| Load calculations for lever bolts and their fitting in relation to braking forces. | 3rd Jun 1932 | Box 15 \ 5 Scan317 | |
| Experimental modification to cones for the Phantom II Synchro Gear Box. | 3rd Jun 1932 | Box 15 \ 5 Scan318 | |
| The strength of helical gears in S. M. gearboxes, stating that angles up to 33° are acceptable. | 4th Jun 1932 | Box 15 \ 5 Scan319 | |
| Oil dip stick for the Phantom II Synchromesh gearbox. | 7th Jun 1932 | Box 15 \ 5 Scan320 | |
| Blueprint drawing for an Oil Dip Stick PII Synchromesh. | 7th Jun 1932 | Box 15 \ 5 Scan321 | |
| Stamped document from the print room in Derby. | 7th Jun 1932 | Box 15 \ 5 Scan322 | |
| Instructions for the Test Department regarding cars fitted with a Phantom II Synchromesh gearbox. | 7th Jun 1932 | Box 15 \ 5 Scan323 | |
| Proposed modification to the 20/25 HP and Phantom II gearbox, to make the first gear independent of the reverse gear. | 17th Jun 1932 | Box 15 \ 5 Scan324 | |
| Clearance adjustment for a 1st speed pinion on a gearbox. | 17th Jun 1932 | Box 15 \ 5 Scan325 | |
| Design changes and material considerations for the P.2 & 25HP model's reverse gear. | 23th Jun 1932 | Box 15 \ 5 Scan326 | |
| Criticisms and proposed modifications for the gear control on 25HP and other models. | 25th Jun 1932 | Box 15 \ 5 Scan327 | |
| Testing of a reverse shaft and potential gearbox modifications for the P.2. and 25-HP models. | 27th Jun 1932 | Box 15 \ 5 Scan328 | |
| Issues with the 1st gear sliding pinion working out of mesh and the subsequent modification to the splines. | 11th Jul 1932 | Box 15 \ 5 Scan329 | |
| Dimensioned drawing of a 1st speed sliding pinion (PII) with modifications to reduce spline length. | 11th Jul 1932 | Box 15 \ 5 Scan330 | |
| Stamped blank page from the Print Room in Derby. | 11th Jul 1932 | Box 15 \ 5 Scan331 | |
| Specifications and use of a gear lever reverse stop spring. | 19th Jul 1932 | Box 15 \ 5 Scan332 | |
| The performance of the Phantom II first gear, its tendency to mesh under load and disengage when braking downhill. | 20th Jul 1932 | Box 15 \ 5 Scan333 | |
| Query regarding the procedure for checking the tightness of Phantom II Synchro Mesh Fabric Coupling Bolts. | 12th Apr 1938 | Box 15 \ 5 Scan334 | |
| Instruction to proceed with synchromesh gearboxes for Phantom II N.2 and O.2 series chassis. | 11th Aug 1932 | Box 15 \ 5 Scan335 | |
| Modifications to the gear lever shaft for the 25HP model concerning gear control. | 13th Aug 1932 | Box 15 \ 5 Scan336 | |
| Fitting of a synchro mesh gearbox to a P.2 trials car. | 4th Aug 1932 | Box 15 \ 5 Scan337 | |
| Future gearbox design, focusing on arranging a helical second speed for quieter operation. | 7th Sep 1932 | Box 15 \ 5 Scan338 | |
| Chronic 2nd gear noise, weighing the use of synchromesh against a proposal for helical gears. | 12th Sep 1932 | Box 15 \ 5 Scan339 | |
| The advantages of a free pinion on the layshaft for the Helical 2nd Gear of the Phantom II gearbox. | 20th Sep 1932 | Box 15 \ 5 Scan340 | |
| Gearbox design options, specifically the placement of a freewheel and jaw clutch and the merits of straight versus helical gears. | 1st Oct 1932 | Box 15 \ 5 Scan341 | |
| Standardisation document for the synchromesh gearbox. | 12th Aug 1932 | Box 15 \ 5 Scan342 | |
| Standardization form for chassis parts, detailing costs and implementation. | 29th May 1938 | Box 15 \ 5 Scan343 | |
| Rattle issue with the Phantom II Synchro Mesh Gear Box due to excessive clearance. | 21th Oct 1932 | Box 15 \ 5 Scan344 | |
| Clutch rattle issue, its potential source, and comparison with the 20/25HP model. | 21th Oct 1932 | Box 15 \ 5 Scan345 | |
| The failure of a 3rd motion shaft in gearbox 19-EX and a proposal for a design modification. | 31th Oct 1932 | Box 15 \ 5 Scan346 | |
| Blueprint drawing for a 3rd Motion Shaft. | 28th Oct 1932 | Box 15 \ 5 Scan348 | |
| Strengthening the gearbox 3rd motion shaft after a failure. | 2nd Nov 1932 | Box 15 \ 5 Scan349 | |
| Failure of the 3rd motion shaft in synchromesh gearboxes and proposed design improvements. | 3rd Nov 1932 | Box 15 \ 5 Scan350 | |
| Customer complaints of 'back lash' noise in Synchro Mesh Gear Boxes for the 20/25HP & Phantom II models. | 3rd Nov 1932 | Box 15 \ 5 Scan351 | |
| Development of a silent second speed gearbox and comparing it to competitors. | 22th Nov 1932 | Box 15 \ 5 Scan352 | |
| Gearbox development, specifically the synchro-mesh second speed and epicyclic gear. | 22th Nov 1932 | Box 15 \ 5 Scan353 | |
| Introducing a silent helical second gear and modified reverse gear into the standard gearbox. | 28th Nov 1932 | Box 15 \ 5 Scan354 | |
| Technical query sent to the Experimental Department regarding the lubrication of the servo drive in a gearbox. | 30th Nov 1932 | Box 15 \ 5 Scan355 | |
| Tests to determine power losses in a Phantom II gearbox due to the helical second gear. | 2nd Dec 1932 | Box 15 \ 5 Scan356 | |
| Graph showing power losses for a PII Synchromesh Gear Box against 1st motion shaft speed. | 1st Dec 1932 | Box 15 \ 5 Scan357 | |
| Blank page marked with a 'Print Room' stamp from Derby. | 1st Dec 1932 | Box 15 \ 5 Scan358 | |
| Issues with helical second gears and proposed modifications to gearboxes for P.II, Peregrine, and 19-EX models. | 5th Dec 1932 | Box 15 \ 5 Scan359 | |
| Possibilities and issues with the Phantom Gearbox synchromesh 2nd speed. | 8th Dec 1932 | Box 15 \ 5 Scan360 | |
| Instruction to fit a bronze thrust ring to the long pattern reverse gear for a Phantom II model. | 9th Dec 1932 | Box 15 \ 5 Scan361 | |
| Experimental modification to the Phantom II gearbox concerning an oil trough. | 12th Dec 1932 | Box 15 \ 5 Scan362 | |
| The new reverse gear and lubrication of the servo drive for the Phantom II Synchromesh gearbox. | 12th Dec 1932 | Box 15 \ 5 Scan363 | |
| Gearbox lubrication performance at different gradients. | 12th Dec 1932 | Box 15 \ 5 Scan364 | |
| Modifications to the reverse gear thrust surface and the servo drive lubrication system. | 17th Dec 1932 | Box 15 \ 5 Scan365 | |
| Modifications for the helical 2nd speed gearbox of the Phantom model. | 11th Jan 1933 | Box 15 \ 5 Scan366 | |
| Seizures of 3rd speed wheel bearings and related lubrication issues. | 25th Jan 1933 | Box 15 \ 5 Scan367 | |
| Remarks on the control of a proposed 40/50 epicyclic gearbox. | 28th Feb 1933 | Box 15 \ 5 Scan368 | |
| The testing of helical second speed gears on Peregrine, 20/25, and 40/50 chassis. | 25th Mar 1933 | Box 15 \ 5 Scan369 | |
| Modifications to the change gear lever to prevent rattles and improve its operation. | 28th Mar 1933 | Box 15 \ 5 Scan370 | |
| Standardisation of Reverse Gear GL.595 Long Pattern. | 12th Dec 1932 | Box 15 \ 5 Scan371 | |
| Standardisation document for chassis parts detailing costs, test date, and the first chassis to be fitted with a new part. | 11th Feb 1933 | Box 15 \ 5 Scan372 | |
| Modifications to the change gear lever mechanism. | 13th Apr 1933 | Box 15 \ 5 Scan373 | |
| Query regarding the operation of the silent second speed feature and if double-clutching is required for downshifting. | 3rd May 1933 | Box 15 \ 5 Scan374 | |
| The silent second speed on the 40/50 HP chassis, noting the need to double clutch. | 4th May 1933 | Box 15 \ 5 Scan375 | |
| Standardisation of Helical 2nd Gear N. Sch. 3631 to reduce gear noise. | 3rd Feb 1933 | Box 15 \ 5 Scan376 | |
| Standardisation form for a new part to be fitted to chassis, including costs and test dates. | 25th May 1933 | Box 15 \ 5 Scan377 | |
| Modifications to the 2nd speed dogs for Bentley, 20/25, and Phantom models. | 2nd Jan 1934 | Box 15 \ 5 Scan378 | |
| Weights of Vulture, 40/50 HP, and 20/25 HP gearboxes and components. | 30th Jan 1934 | Box 15 \ 5 Scan379 | |
| Correcting the suggested placement for the filling plug and level stick on the P.2 S.M. 2nd Gearbox. | 6th Mar 1934 | Box 15 \ 5 Scan380 | |
| Issues and modifications for a synchromesh 2nd speed gearbox fitted to a Vulture chassis. | 7th Mar 1934 | Box 15 \ 5 Scan381 | |
| Gearbox issues, including gear wear, noise, and engagement problems, with proposed modifications. | 7th Mar 1934 | Box 15 \ 5 Scan382 | |
| Changes to the gear and brake levers for the Phantom S.M. 2nd model. | 22th Mar 1934 | Box 15 \ 5 Scan383 | |
| Internal memorandum regarding modifications to the P.2. S.M. 2nd Gearbox. | 23th Mar 1934 | Box 15 \ 5 Scan384 | |
| Urgent inquiry regarding the production status of the Second Speed Synchromesh Gearbox for the 40/50 HP model. | 29th Mar 1934 | Box 15 \ 5 Scan385 | |
| The design and casting status of the Second Speed Synchromesh Gear Box for the 40/50 HP model. | 4th Apr 1934 | Box 15 \ 5 Scan386 | |
| Progress report on the second speed synchromesh gearbox for the 40/50 HP chassis. | 5th Apr 1934 | Box 15 \ 5 Scan387 | |
| Modifications to the P.2. S.M. 2nd Gearbox, including changes to the gear gate travel and reverse shaft. | 17th Apr 1934 | Box 15 \ 5 Scan388 | |
| Modifications to the P.2. S.M. 2nd Gear/Brake Levers, reverting to an inclined handle. | 4th May 1934 | Box 15 \ 5 Scan389 | |
| Requesting the deletion of an adjustment washer for the P.2 S.M. 2nd Gearbox layshaft. | 5th Jun 1934 | Box 15 \ 5 Scan390 | |
| Standardisation of parts for backed off second speed dog teeth. | 23th Apr 1934 | Box 15 \ 5 Scan391 | |
| Cost estimation for extra jigs, tools, and equipment related to a part standardization. | 10th Sep 1934 | Box 15 \ 5 Scan392 | |
| Excessive end load on the second gear sliding piece of a 28-EX gearbox. | 6th Jul 1934 | Box 15 \ 5 Scan393 | |
| Alterations for a P.2. S.M. 2nd Gearbox before reassembly. | 7th Jul 1934 | Box 15 \ 5 Scan394 | |
| Provision of oil grooves for the P.2. S.M. 2nd Gearbox. | 9th Jul 1934 | Box 15 \ 5 Scan395 | |
| The trial of weaker selector rod springs for the P.2. S.M. 2nd Gearbox. | 17th Jul 1934 | Box 15 \ 5 Scan396 | |
| Improvements to the P.2. S.M. 2nd Gearbox using wider cones and ball bearings. | 19th Jul 1934 | Box 15 \ 5 Scan397 | |
| Gearbox features for the 28-EX car before its dispatch to France. | 23th Jul 1934 | Box 15 \ 5 Scan398 | |
| Modification to the P.2. S.M. 2nd Gearbox speed actuating lever. | 23th Jul 1934 | Box 15 \ 5 Scan399 | |
| Modifications to the P.2. S.M. gearbox 2nd speed sleeve to reduce friction. | 23th Jul 1934 | Box 15 \ 5 Scan400 | |
| Modifications to a P.2. S.M. 2nd Gearbox to lighten its actuation. | 23th Jul 1934 | Box 15 \ 5 Scan401 | |
| Modifications to the gearbox gate for the Phantom and Spectre models. | 27th Jul 1934 | Box 15 \ 5 Scan402 | |
| Schematic for the vent on a P.2. S.M. 2nd Gearbox. | 27th Aug 1934 | Box 15 \ 5 Scan403 | |
| Revisions to the P.2. S.M. 2nd Gearbox, including a new vent, spherical bearing and spring loading. | 4th Sep 1934 | Box 15 \ 5 Scan404 | |
| Confirming a conversation to put in hand another Phantom synchromesh second box. | 7th Sep 1934 | Box 15 \ 5 Scan405 | |
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