A project, not a service tank
The Tank, Mark VI was a proposed British heavy tank represented by a wooden mock-up. It did not enter production or operational service. The full-size model illustrates a proposed layout, not a completed armored vehicle that underwent powered trials. Sources
The published family, variant/project, and prototype/paper records refer to the same development effort. The designations describe one project rather than three separate tanks. The available evidence also contains a relationship to the Flying Elephant, but that mapping conflicts with other the cited accounts lineage entries. The connection remains under review rather than becoming an accepted Mark VI production variant. Sources
The 1917 heavy-tank proposal was distinct from the much later British Light Tank Mark VI. The shared numeral does not indicate direct continuation of the same design. Sources
Development intentions and the mock-up
The proposed Mark VI sought a more substantial rearrangement than the incremental improvements leading into the Mark IV. Accounts describe a fixed raised fighting position and a forward main gun, in contrast with the familiar large gun sponsons of earlier British heavy tanks. These features offered a different approach to layout and firepower, but they also meant changes to manufacturing arrangements. Sources
The source narrative includes Albert Stern’s account of April 1917 discussions and a plan for a wooden model incorporating an engine. A planned readiness date is not a completed-vehicle trial. The museum account cited in Published accounts describe the wooden mock-up at Metropolitan’s Birmingham works on 23 June 1917; a separate July inspection claim remains a dated event to check, not a substitute for the June record. Sources
The distinction between a model, installed components, and a working armored prototype is essential. The terms describe different stages of completion rather than interchangeable evidence of an advanced prototype. The available photograph records an external wooden representation; it does not supply measured mobility, ballistic protection, or reliability evidence. Sources
American interest forms part of the project’s procurement context. Published accounts describe a secondary claim about an order for six hundred Mark VIs. Evidence for a later six-hundred-tank arrangement involving the Mark VIII cannot independently prove the same commitment for the Mark VI. The two programs need their own documents and dates. Sources
Proposed technical arrangement
The planned layout used a fixed upper fighting compartment rather than a rotating turret. The main armament was proposed in the forward hull, with machine-gun positions distributed in the design. The source describes a 6-pounder and reported Hotchkiss installations, but detailed counts and arrangements remain proposed specifications. They are not the tested equipment of a completed service vehicle. Sources
The available evidence associates a Ricardo engine of about 150 horsepower, revised control arrangements, wider tracks, and an estimated weight with the project. Published speed and range figures are also design estimates. The quoted values are design figures, not demonstrated road trials, cross-country tests, or service endurance results. Sources
Armor figures vary in the source material. The wooden mock-up cannot establish the thickness or ballistic quality of the steel that a finished vehicle would have received. Likewise, exact ammunition stowage, sights, internal crew tasks, and maintenance access are not all securely documented. A proposed arrangement does not become a confirmed final specification because it can be depicted in a reconstruction. Sources
They also distinguish the Mark VI proposal from associated Flying Elephant material rather than averaging the two into an imaginary vehicle. Sources
Industrial choice, cancellation, and service status
The account explains the Mark VI’s abandonment partly through the consequences of changing the hull and production process while tanks were urgently needed. A more radical design could promise improvements and still be unattractive if it interrupted output. Published accounts describe the decision within the development of other British heavy-tank programs, without establishing that every cancellation explanation in the secondary literature has been reconciled. Sources
There was no Mark VI combat fleet, factory production run, export service, or battlefield employment. Similarly, an unbuilt project has no actual combat loss rate or crew testimony from action. Sources
The wooden mock-up was not a completed service tank; no operational production is established. Costs for another heavy-tank program cannot be borrowed to fill a missing Mark VI unit price. Proposed quantities, budget discussions, and intentions are relevant historical evidence, but they measure different things from deliveries. Sources
Its significance is the choice between a changed design and maintaining a production system during war. There is no measured performance record here against which to validate a claim that the tank would have been faster, safer, or more effective in combat. Sources
The visual record and historical evidence
The account supplies one photograph of the wooden mock-up. The source describes its subject as a model of the proposed Mark VI; location attribution is qualified. The image is useful precisely because it records the design’s external form, but it is not a photograph of a tank in service. Its visible appearance cannot be transformed into a confident operational paint scheme or an imagined battlefield scene. Sources
Additional archive photographs, inspection reports, drawings, and correspondence could strengthen the article. Priority questions include the exact model chronology, the degree of engineering completion, the American procurement claim, the proposed armament fit, and the relationship to other projects. Sources
Unknown details remain acknowledged. The photograph and design descriptions document the Mark VI proposal; they do not establish a completed tank, a performance trial, or a production variant. Sources
Sources and further reading
Background reading and references. Each photograph has its own source and credit.
- S1 — Fletcher, David. "Experimental WWI Tanks - Part I." The Tank Museum, 12 May 2017.
- S2 — Stern, Albert G. Tanks, 1914-1918: The Log-book of a Pioneer. Hodder and Stoughton, 1919. Internet Archive full text.
- S3 — Moore, Craig. "Tank Mark VI." Tank Encyclopedia, 15 April 2017.
- S4 — "File:MarkVITankWoodenMockup1917.jpg." Wikimedia Commons.
- S5 — Imperial War Museums collection record, catalogue number Q 14521, Department of Tank Design and Experiment Collection.
- S6 — Cogan, Robert L. "The Mark VIII Tank: The First Joint Armor Program." Line of Departure / Army History, U.S. Army, 1 June 2024.
- S7 — Accessed 2026-05-31.
- S8 — Accessed 2026-05-31.
- Trackpads historical compilation, 2026 (unpublished).
