Hank49:
For the benefit of all n00bs reading this thread who've never dived beyond 60 feet I feel this should be said. IF YOU DO for whatever reason, find yourself at 200 feet (maybe you didn't pay attention dropping down the quarry or reef wall. I've seen it happen) trust me, you're not going to die. The ppO2 is 1.4 on air so you're not likely to black out. You will be narced but it isn't all bad. You COULD have an equipment failure but that's about as likely as having a front tire blow out going 70 mph down the freeway. Just keep a cool head and start your accent. You can go faster than normal (2 ft/sec) up to 140 feet too because the % pressure change is like going from 30 to 20 feet. From there go 1 ft per second to 30 feet and stop for 3-5 minutes (if you have computer, follow directions) proceed to 20 feet and stop for another 5, go to 10 feet and stop until your air is low. I've read a lot of posts here that make it seem like it can't be done and you'll die trying. It can be done and many people do it for fun. Dangerous? yes. But if it happens to you, don't panic. You'll be fine. Hank
Sure ... you can do a 200 foot bounce dive on an AL80. I know someone who did it. He was a student at a local commercial dive school, and had logged about 25 dives. Him and his buddy, when "planning" the dive, decided that they should overweight themselves so they'd sink faster. They swam out over the edge of this wall, deflated, and sank like stones. When they hit the bottom at 212 fsw, they stirred up such a silt cloud they promptly lost each other. One buddy surfaced, the other one didn't. For all anyone knows, he's still down there (this happened two years ago). The guy who never came back was 23 years old and had a wife and two kids.
The name of the dive site ... appropriately ... "Dead Man's Wall".
Can it be done? Sure ... one guy made it back OK.
Is it worth the risk? Your call ...
Edited to add ...
On a serious note ... for the benefit of the n00bs who may be reading this post ...
Diving deep, regardless of the equipment you are using, is not something to be undertaken lightly. The deeper you go, the more dependent on your gear you become ... the more dependent on solid skills you become ... the more dependent on an understanding of the stresses that partial pressures place on your body you become. Undertaking any dive without proper knowledge and training is not something you should think about doing.
The effects of narcosis should not be taken lightly ... I've seen people at 90 feet who are so impaired they lose the ability to control their own buoyancy. Losing buoyancy on a deep dive is like driving drunk ... you might make it home OK, but your chances of it are significantly decreased. And the deeper you dive, the drunker you become.
Irrespective of the size cylinder you are using, diving deep should not be attempted by an inexperienced diver. You simply haven't yet acquired the skills and knowledge to know how to keep yourself out of a situation that can start the chain of events that lead to an accident.
Dive smart ... if you want to go deep, get enough bottom time first to acquire solid diving skills. Choose your dive buddy with care ... on a deep dive, solid buddy skills are essential. Take the time to learn enough about decompression to understand what pressure does to your body ... and how you should plan your ascent to minimize the risk of decompression sickness.
Saying "you'll be OK" assumes that you've acquired those skills ... and will have the thinking capacity to use them. Hank's advice is technically valid, but it assumes you'll be skilled enough and rational enough to actually follow it. At 200 fsw on air, that's not an assumption I'd want to bet my life on ...
... Bob (Grateful Diver)