High And Dry: Watch HMS St Albans Get Ready For Repairs

The Royal Navy has released footage of more than 128,000 tonnes of water being pumped out from a dry dock to make way for HMS St Albans.

The Type 23 frigate is undergoing essential repair works following a nine-month deployment, at one of 10 dry docks in Portsmouth Naval Base.

The water, which could fill around 1,068,333 bathtubs was slowly pumped out of the dock over more than 11 hours.

The ship was kept upright by a series of large wooden beams that braced her side against the dock walls, with cranes levering them into position.

St Albans was kept sitting central using laser alignment, with the precise process of lining her up vital.

All the underwater equipment located on an antisubmarine frigate, including her sonar dome, only has 50cm clearance to the dock bottom once all the water has been drained.

Deputy Marine Engineering Officer Lieutenant Peter Ainscow said:

"Getting into dry dock is a lengthy process but it is essential to carry out essential underwater maintenance that otherwise would be expensive or impractical to be completed in the water by divers or in a habitat."

"All ships incur wear and tear from deployments and HMS St Albans in particular has been operating at a high operational tempo which makes this sort of work necessary for her continued capability."

Maintenance works will include repairs to her underwater fittings and works to her rudders, including painting them, to ensure they are preserved until the next planned maintenance period.

The frigate will be in dry dock for several weeks before water will be allowed back in and she will return to sea.

Dry Docks have been used since the 10th century to allow for maintenance, repair works and construction of ships. Portsmouth Naval base also still has the oldest surviving dry dock commissioned by Henry VII in 1495. This dock currently holds the world's oldest commissioned Warship, HMS Victory.