I feel like the 80 minutes is way to long and not the right time, but I can't remember! lol. Like I said, don't have to be a strong swimmer, comfort ability is more what you need, like not entirely panicking. Probably the most intense water training you will have to go through is the Helo Dunker, where you do multiple underwater escapes out of seats, where they flip you upside down strapped to a seat underwater, you pull a window out and escape through it. Then multiple runs through the helo dunker itself where it descents, flips under water and you go out your designated egress point. You do it like 5 times, couple times without blackout goggles and your emergency air breathing device (mini scuba tank essentially), then a few runs with no oxygen and blackout goggles. This gets a lot of people, but honestly you hold your breath and do what you need to do, going upside down is pretty disorienting, but the trick is not to completely freakout, because its a fairly safe evolution since their are emergency divers watching the whole time. Plus I think you keep your air bottle on you the whole time, so if shit goes bad, grab your mouth piece, and breath.