| Built By: | Vickers (Barrow) |
| Build Group: | XPW |
| Fate: | Preserved in 1977 |
Midget submarine X51 alongside HMS Jupiter, Gareloch, Scotland. 1954
| 01-10-1954 | Launched |
| Length overall | 51 ft 7 inch |
| Beam | 8 ft 6 inch (with charges) |
| 5 ft 9 1/2 inch (without charges) | |
| Displacement | Without Charges: 27 tons (surface) |
| Without Charges: 29 1/2 tons (submerged) | |
| Diving Depth | 300 ft |
| Speed | With Charges: 6.5 knots (surface) |
| With Charges: 5 knots (submerged) | |
| No. of shafts | 1 |
| Armament | 2 x 2-ton side charges, Limpet mines |
| Endurance | Surface: 1320 miles at 4 knots (with charges) |
| Surface: 1860 miles at 4 knots (without charges | |
| Submerged: 80 miles at 2 knots (with charges) | |
| Complement | 4 |
Commander John McGregor OBE Royal Navy Crossed the Bar on August 12th 2025 at the age of 88. After a varied naval career, which included high pressure jobs in nuclear submarines, John McGregor was appointed as Engineer Commander of HMS Fearless in March 1982. At the time he may have thought that this would be a comparatively relaxing job, but all that changed when Fearless sailed with the Task Force for the Falklands War.
This book explores the many engineering and architectural aspects of submarine design and how they relate to each other and the operational performance required of the vessel.
Concepts of hydrodynamics, structure, powering and dynamics are explained, in addition to architectural considerations which bear on the submarine design process.
21 pages added or updated in the last 1 month
Please help to maintain this site by reporting any Errors, Broken Links, Information or Site Issues on this page using this button
If you find this site useful, please consider supporting my work with a small Donation.
Please Note: Donations made using this option go directly to the site owner and not to the Submariners Association.
Thankyou for your support.
| Length overall | 51 ft 7 inch |
| Beam | 8 ft 6 inch (with charges) |
| 5 ft 9 1/2 inch (without charges) | |
| Displacement | Without Charges: 27 tons (surface) |
| Without Charges: 29 1/2 tons (submerged) | |
| Diving Depth | 300 ft |
| Speed | With Charges: 6.5 knots (surface) |
| With Charges: 5 knots (submerged) | |
| No. of shafts | 1 |
| Armament | 2 x 2-ton side charges, Limpet mines |
| Endurance | Surface: 1320 miles at 4 knots (with charges) |
| Surface: 1860 miles at 4 knots (without charges | |
| Submerged: 80 miles at 2 knots (with charges) | |
| Complement | 4 |
Commander John McGregor OBE Royal Navy Crossed the Bar on August 12th 2025 at the age of 88. After a varied naval career, which included high pressure jobs in nuclear submarines, John McGregor was appointed as Engineer Commander of HMS Fearless in March 1982. At the time he may have thought that this would be a comparatively relaxing job, but all that changed when Fearless sailed with the Task Force for the Falklands War.
This book explores the many engineering and architectural aspects of submarine design and how they relate to each other and the operational performance required of the vessel.
Concepts of hydrodynamics, structure, powering and dynamics are explained, in addition to architectural considerations which bear on the submarine design process.
21 pages added or updated in the last 1 month
Please help to maintain this site by reporting any Errors, Broken Links, Information or Site Issues on this page using this button
If you find this site useful, please consider supporting my work with a small Donation.
Please Note: Donations made using this option go directly to the site owner and not to the Submariners Association.
Thankyou for your support.

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