Ian Moore – First experience of SETT
They were trying to turn me into a fish. Quite literally, they want me be a fish. They want me to breathe under water. The SETT itself is 100-foot tower with various locks that you can actually access the tower through the side of the tower, at 30 feet, 60 feet and 100 feet.
Essentially what they’re trying to do is that during s submarine escape, they want you to be able to understand what it actually means to escape from a dived submarine, and I was one of the last ones where you actually did the so-called free ascent from the bottom of the Tank. The free ascent is where you are breathing out all the way to the surface, so you’re breathing out all the way to the surface from 100 feet down.
The air that you’re breathing at 100 feet has been highly compressed, so that the air that you’re taking into your lungs is probably about ten times normal atmospheric pressure, so us breathing now, if you can imagine ten times that volume of air going down into your lungs, that’s what you’ve got at 100 feet if you’re breathing compressed air. When they open out the access into the Tank itself, and you’ve got 100 feet of water above you and you’ve got a couple of safety numbers either side of you, and you need to prove to them that you can actually breathe out properly, which literally is just blowing out.
Pursing your lips to about the size of a pencil, and then just breathing out and then they’ll release you. And then you breathe out all the way to the surface, so you’re breathing out for essentially about 12 seconds, 13 seconds, 14 seconds or however long it might take you, depending on what your personal buoyancy is. But you’re breathing out all the way to the surface. At some point or other, once or twice, you can actually run out of air and you think you’re going to die, because you’re out of air and you’re still only halfway to the surface.
And by the time you’ve actually thought of that, you’ve actually gone up another 2,3,4 feet, and the air inside your lungs has now expanded out again to take into account that lessening of the pressure on you. Suddenly your lungs start to feel so full of air that you’ve really got to blow out really hard, so effectively you’re the same as a fish.
You’ve run out of air, and now you’ve got more air. How does that work? (laughs). So now you’re breathing out again but having to breathe out really hard because you’re trying to get rid of this … because your lungs are now starting to hurt because they’re expanding so much …
Simon: You feel the hurt in your lungs?
You can feel it.
Simon: You’re filling your chest.Ian You can feel it filling your chest up.
You’ve got to blow really hard to get rid of this air as fast as you possibly can. And then you break the surface and you lie there on the surface and one of the Swim Boys will actually drag you over to the side, and then they’ll make you stand on the side of the Tank to make sure that you’re actually ok.
When you’re actually at the bottom of that Tank and you’re about to do it, the panic that runs through you is like nothing on earth, and when you hit the top of the Tank, all you want to do is do it again. Absolutely fantastic. Brilliant.