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Submarine Escape Training Tank

SETT tower
SETT tower


SETTInside ariel view of SETT The Submarine Escape Training Tank (SETT) was built in 1954, after a review of submarine incidents showed that many submariners were not well equipped or trained for escaping from submarines.


The Tank supports a 100ft column of fresh, chlorinated water. Apart from occasional shut-down periods for maintenance work the tank has been operational continuously since it was first commissioned. Approximately 1,500 submariners per year in addition to submariners from other navies are trained at the SETT.


Escape training
Escape training 

SETT instructor staff are all qualified Royal Navy submariners, who have volunteered for the Tank. It takes about four months to train them to a level at which they can train other submariners.

The instructors train new entry submariners and existing submariners re-qualifying in escape and rescue techniques for submarines.

At SETT different methods of escaping from a distressed submarine are taught. The preferred method of getting people out is by manoeuvring a submersible alongside the submarine and attaching it to either the forward or aft escape hatches. Crew of the submarine can then escape by climbing in to the rescue submersible.

Problems with Submarine Rescue

Floor planSETT floor plans Rescue submersible are small, typically with a carrying capacity of 15, many trips may be necessary to rescue a submarine crew which may number 150. During this period the submarine may suffer further flooding or may become unable to maintain a breathable atmosphere.

Crew are also trained to escape from the submarine without external assistance if it is not too deep. The present systems have been used down to 180m. The submariner needs to involuntarily become a diver, being able to exhaust air from his lungs during the ascent to the surface. Various apparatus can be used to assist with the ascent, including suits and various ascent aids.

SETT Statistics
100ft deep (30m)
18.25ft diameter (6m)  
150,000 gallons (approx. 1m pints)  
Thermo-neutral temp 34C/94F  

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