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!style="color: white; height: 30px; background: navy no-repeat scroll top left;"|Career
!style="color: white; height: 30px; background: navy no-repeat scroll top left;"|image:RN-White-Ensign.svg60px|RN Ensign
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|Ordered:
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|Laid down:
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|Launched:
|August 1966
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|Commissioned:
|September 1967
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|Decommissioned:
|1991
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|Fate:
|On display to the public
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|Struck:
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!colspan="2" align="center" style="color: white; height: 30px; background: navy no-repeat scroll top left;"|General Characteristics
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|Displacement:
|1610 tons surfaced and 2410 tons submerged.
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|Length:
|88.5m
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|Beam:
|
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|Draught:
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|Propulsion:
|Diesel / Electric, 2 shafts.
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|Speed:
|17 knots submerged.
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|Range:
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|Complement:
|62
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|Armament:
| 6 forward 21 inch torpeado tubes, 2 aft 21 inch torpedo tubes (later removed).
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|Motto:
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The '''HMS ''Onyx''''' was an Oberon class submarine''Oberon'' classsubmarine of the Royal Navy. Originally ordered for the Royal Canadian Navy, ''Onyx'' was transferred to the Royal Navy whilst under construction at Cammel Laird shipbuilders in Birkenhead, England. She was launched on August 1966 and commissioned into the Royal Navy in September 1967.
The first commission of the ''Onyx'' saw her visit Swansea in South Wales for the investure of His Royal Highness Charles, Prince of WalesThe Prince of Wales. She also attended the bicentennial celebrations of the United States of America in 1976.
HMS ''Onyx'' was the only non-nuclear submarine of the Royal Navy to take part in the Falklands War. The smaller displacement of ''Onyx'' compared to the nuclear submarines made her ideal for landing Special Air ServiceSAS and Special Boat ServiceSBS troops close to the Falkland Islandsislands in shallow waters.
Defence cuts in the United KingdomUK saw the Royal Navy dispense with its diesel-powered submarines to concentrate on nuclear attack submarines. In 1991, the ''Onyx'' was decommissioned from the navy. She is now cared for by the Warship Preservation Trust and is on public display alongside several other ships in Birkenhead, United KingdomUK.