Good advice Jay. Can't imagine how long it might take the navy to show up, but I'm guessing if anybody can do it. it's them. This thread makes me want to reconsider the whole "tether" idea.
If I have two 80's scuba tanks on board, and my ballast tanks come in at 175 gallons, then I should be able to blow the tanks 6-2/3 times, if at the surface.( Assuming no air lost in bubbles.)
with another 80 scuba tank in reserve, that's a total of 9 blows. If I use a larger 140 cu. ft. weld tank, it's 11 blows. Now remember, that's at the surface and doesn't account for any other air usage or waste.
How many blows, or what is the ballast capacity of the standard K boats? They must be fairly close to 100 gallons aren't they? Don't most guys use two scuba tanks on their boats?
Who has a K boat out there that knows what their gallons of ballast is? It would be good to hear the real facts from one of our guys who can say what it takes to go out for the day. It's probably a good idea to keep a second and maybe a third set of tanks available on the surface boat or at least in the truck.
You need the tanks for the stand-by divers anyway. Frank D.