THE centrepiece of the new Scottish Submarine Museum in Helensburgh – a former Royal Navy 'midget' submarine – has arrived in Scotland.

The 50-foot-long submarine, X-51, was brought north to HM Naval Base Clyde from storage at the Portsmouth Historic Dockyard, and reached the Faslane base on Wednesday evening.

The 39-tonne vessel, which has been donated by the Royal Navy, was launched in 1955 and named HMS Stickleback in the same year.

It's expected that she will be moved from the base to the new museum in West King Street in the next few weeks.

X-51 was transported to Scotland by Dumbarton-based haulage firm Galt Transport – a sponsor of the new museum – in two parts, with the main body of the submarine and the craft's engine travelling separately.

Work is well under way on preparing the museum, which will occupy part of the former St Columba's Church on the corner with Sinclair Street, for its new exhibit.

The museum - Helensburgh's first purpose-built visitor attraction - is due to open later this year.

X-51, which was previously on display at the Imperial War Museum in Duxford, is a direct descendant of the midget submarines used in some of the most daring raids of the Second World War, including the audacious attack on the German battleship Tirpitz.

Those WW2 midget submarine crews underwent their initial training around the Firth of Clyde, having been based at HMS Varbel – the wartime name given to the requisitioned Kyles of Bute Hydropathic Hotel, at Port Bannatyne on the Isle of Bute.

Though X-51 will be the focal point of the museum, other exhibits will also include an interactive memorial in remembrance of the men who gave their lives as members of the Royal Navy submarine service.