I teach the SDI basic wreck course and the TDI Advanced Wreck class. My feeling is that you really need to start looking at the TDI course as a natural progression and so I include line work on at least half the dives. Depending on the student and schedule I like to have 6 dives min for the SDI course.
The first dive is a general survey with lots of attention to making notes on the wreck. Orientation, type, overall layout and some line work to survey and take measurements.
Next dive is a more detailed survey where we go over the target area paying special attention to risk points. How stable is it? Where are the sharp edges that can cut a line or the diver? Where is it possible to encounter line that might entangle a diver? What structural defect are there?
Dive three is identifying entry and exits. Making a sketch of them and doing a look inside each without actually going in. A mirror is part of this.
Dive four is more line skills including showing a diver what getting caught in a line feels like. Or more what it does not feel like. Most people expect to be brought up short suddenly and stopped in their tracks. Doesn't always happen that way. Just slipping a line over a fin buckle in open water and letting the diver swim shows them that it can be very subtle to become entangled.
Dive five is a short penetration within the light zone, using a line, practicing tie offs, and an air share swim out and buddy swimming a non responsive buddy out while following the line.
Dive six is the spider web. basically swim through an area with lines running every which way in it. Idea is to go very slow, pick the route, and don't get tangled. They always do though. Enough to show them that they really have no business inside at the recreational level. Every student I have had that went through this made a similar observation. That the guided dives they may have done in the tropics and other places where a guide them led in a wreck was a disaster waiting to happen. They saw just how easy and how subtle it could be to get in real trouble. They also stated that they would not do that again. That they'd stay on the outside or call the dive.
The first dive is a general survey with lots of attention to making notes on the wreck. Orientation, type, overall layout and some line work to survey and take measurements.
Next dive is a more detailed survey where we go over the target area paying special attention to risk points. How stable is it? Where are the sharp edges that can cut a line or the diver? Where is it possible to encounter line that might entangle a diver? What structural defect are there?
Dive three is identifying entry and exits. Making a sketch of them and doing a look inside each without actually going in. A mirror is part of this.
Dive four is more line skills including showing a diver what getting caught in a line feels like. Or more what it does not feel like. Most people expect to be brought up short suddenly and stopped in their tracks. Doesn't always happen that way. Just slipping a line over a fin buckle in open water and letting the diver swim shows them that it can be very subtle to become entangled.
Dive five is a short penetration within the light zone, using a line, practicing tie offs, and an air share swim out and buddy swimming a non responsive buddy out while following the line.
Dive six is the spider web. basically swim through an area with lines running every which way in it. Idea is to go very slow, pick the route, and don't get tangled. They always do though. Enough to show them that they really have no business inside at the recreational level. Every student I have had that went through this made a similar observation. That the guided dives they may have done in the tropics and other places where a guide them led in a wreck was a disaster waiting to happen. They saw just how easy and how subtle it could be to get in real trouble. They also stated that they would not do that again. That they'd stay on the outside or call the dive.