Howdy!
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From TSA's web site:
http://www.tsa.gov/public/interapp/editori...torial_1190.xml
Transporting Scuba Equipment
Some scuba gear can be transported on-board the aircraft. Please refer to the guidelines below:
Regulators, Buoyancy Compensators and mask, snorkel and fins are all acceptable as checked or carry-on baggage.
Dive tanks or any compressed gas cylinders are prohibited from carry-on and checked luggage. (Emphasis mine.)
Knives and tools are prohibited from carry-on luggage. These items should be packed in checked luggage. Any sharp objects packed in checked luggage should be sheathed or securely wrapped to prevent injury to baggage handlers and security screeners.
Spear guns are prohibited from carry-on luggage. These items should be packed in checked luggage.
Now, stating that "...gas cylinders are prohibited... would seem to prevent carrying pony bottles and other bail-outs, even Spare Air. However:
(1) Some reports state that if you unscrew the valve from the cylinder, they no longer consider it a gas cylinder; and
(2) I can be much too bull headed for my own good, I know - and I have flown to/from Roatan, California, North Carolina, Cozumel twice, and Florida in the last year without bothering to remove the valve. No problems.
It seems that the TSA security guards are taking their information from the airlines, most of whom allow tanks in checked luggage, some even allowing up to 40 psi. I always drain mine completely, so if the TSA agent opens the valve, he'll see that there's no pressure, even though that proves nothing. It might be that these government employees aren't bothering to read their agency's instructions?!
For this weekends flights to California, though - I have removed the valve from the tank; I dunno', just a hunch. I know I won't bother on the return flight.
At the worse, if a TSA agent ever confiscates my 19 cf tank, I'll be out a little more than $150 to replace it & the tiny SPG attached to it, as I'll still have the complete reg. To me, that's an acceptable risk, easier to accept than diving without a Pony - with some of the buddies I've been assigned at times! I wonder if a traveler had his tank without valve taken, but still had the valve - could a replacment tank without valve be purchased? Probably, but then the savings might be small.
BTW, the purpose of a Pony bottle is for bailouts only, when my primary system may fail, or when sharing air with another diver drains my primary tank too fast with us both on it; it is not to be used to extend normal dive time. At the end of a trip, I even drain my tank while still on the boat to quietly illustrate that I did not cheat.
And - I carry a 19 cf Pony. I know that many only carry 6 to 13 cf Ponies, but I figured that a 19 cf tank would have 23.75% of the capacity of a standard 80 cf tank, which would be the equivelent to 712 psi of a 3,000 psi load on a standard 80 cf. I would hate to have to ascend from many of the dives I do with any less than 700 psi left for a slow ascent and safety stop. A 13 cf Pony would be equivalent to on 487 psi portion of a standard 80 cf tank, a 6 cf would be like 225 pis of a standard 80. (PM me if you want to see the math.)
Plus, my Pony is marked crudely in magic marker "Air only." As difficult as Nitrox is to find in some locations and shops, and as important as O2 clean is to Nirrox filling, I would not want anyone to try pumping pure O2 into a tank I've breached. Ka-Boom!
don
BTW - it would really help in future discussion if you'd complete your Profile. Click "User CP" upper left of this page, then go down to "Edit Profile."
