Developement of Submarine Escape Training

In the 1930ís and 1940ís Submarine Escape Training was conducted in a 15 foot tank, located within Fort Blockhouse,Gosport, Hants. The DSEA set was the equipment used in this facility, not all Submariners were trained to use this equipment.
Commissioned and the first training class was conducted in July 1954.
Teaching Compartment Rush Escape, which was the only method of escape used for S/M Escape at this time. (Buoyant Exhaling Ascent).


History of the DSEA Tank
Click on Image

The Buoyant Exhaling method of ascent is still taught today (right).
Students will continue to demonstrate the correct blowing rate.
However, they no longer make an ascent through the water column due to Health & Safety restrictions associated with training in a pressurised environment. Trainees would have completed two ascents from 9 metres and one ascent from 18 metres before conducting a 30 metre hooded ascent.

Pressurised Escape Training


The first hooded ascent was conducted in 1965. This method allowed escapees to breath normally during the ascent.


Whilst in the tower the escapee will plug into an air supply, this air will then expand during the ascent and vent into the hooded area allowing the escapee to breath normally all the way to the surface. (30 metre Hooded ascent)


Bill Wyatt (Instructor 1950-1955)

When I joined the SETT we only had the 15' tank.

Training: A DSEA set was the only equipment used, a lecture was given on compartment escape, the gun and conning tower could be used if you were lucky.

After the lecture the class put on DSEA suits, the drill for using them was carried out, they then entered the water at the top of the tank and went under so that they could see and feel what it was like to breathe under water.
They then went into the compartment, I think you could only get 8 men in at a time, you again went through the drill as you flooded up, the twill trunk being down of course, they then escaped and carried out the surfacing routine on arrival at the surface. If you didn't do it properly you could soon return to the bottom.
The DSEA set was OK if you did everything correctly. The first ones had a poorly positioned relief valve and it could be missed by someone who was in a nervous state with fatal results in an actual escape. A new set came out with a better valve and a better position. One must remember you were breathing pure oxygen from a small supply.

Mike Murton swimboy SETT 1957-59.
As I recall but it is a long time ago, the daily work varied to a degree but mainly we spent 210 minutes in the forenoon and 180 in the afternoon. Usually we had two instructors in the water diving down from the surface one at 45ft and one at 90ft operating from air blisters and two in the diving bell. The object of the exercise was to supervise the ascent of the trainees ensuring that they were breathing out at a steady flow as they had been instructed,if not we applied pressure to their solar plexus which would do the trick. The course comprised of lectures given by the Coxswains, a test in a compression chamber equal to a depth of 200ft, then to the tank, here the students were tested for buoyancy at the surface then two ascents from 30 ft and one from 60ft and finally one from the submarine simulation at 100ft On reaching the surface they remained standing for four minutes to ensure they had not caused themselves to have an air embolism. In the unlikely event of this happening they were put straight into a de-compression chamber for up to 24 hours until embolism had passed out of the system. They would be accompanied by at least one member of staff at all times, as it was quite lucrative job we were enthusiastic about getting in to the POT as it was called. In my time, their was about four occasions and only one serious, a surgeon ironically who tried to swim to the surface completely forgetting the drill. He did eventually recover but did not join the submarine service. We used to carry out shows as they still do demonstrating escapes larks like ascending with a bucket over ones head and dropping from the surface walking across the bottom and climbing up the other side all on one lungful of air. With regard to equipment we used to have only goggles which had a balloon each side which used to crush as we went down this prevented the goggles becoming uncomfortable. Initially the trainees used to wear a life jacket which had a relief valve to allow the pressure to release as they came up to the surface, on the final run from 100ft they were fitted out with a survival suit which they inflated on the surface.

Developement of Escape Training

Developement of Escape Training Equipment

Return to Surface

©2006 Ian Callow