Carrying scuba tanks in private plane

[Belmont]

I plan a 3 hour trip in a Cessna 172 and I'll be bringing my twin 130's.

My questions:

1- I know that aviation rules don't permit carrying pressurised cylinders on a commercial flight, is it allowed on a private small plane?

2- (This might have been covered here) If I have to empty and remove the valves is there a risk of causing rust to appear inside my tanks? They are going in for a visual and O2 cleaning.

Thanks in advance.

 

[livewire]

On question 1, I have no idea if it's allowed, but usually on something like this its up to the individual pilot. When I've flown with private pilots before, their rules were much more relaxed. For example, I was talking on the cell phone in the co-pilot seat as he was getting clearance and taxiing over to to the runway for take-off. When I asked if it was okay, he said he did it all the time! Honestly with valves off I think it will be fine. I'd be more concerned about a weight limit with that plus your other gear and whatever else you're packing.

On question 2, I believe there is only a risk if you're exposing the tanks to a lot of moisture. I assume we're talking about a 3 hour flight in dry air, so in that case they'll be fine. I've performed VIPs where the valve was off for longer than 3 hours because of silly distractions in the shop or stupid stuff like trying to find an o-ring for the valve... Okay, I'm sort of a slacker, but I don't think you have that much to worry about here, especially if the tanks are going in for another vip and cleaning afterwards.

 

[pilot]

Just think about this: Supplemental O2, when carried in a private plane, is in a pressurized cylinder. So the main concern you will have in a 172 is weight and balance, especially if you are not alone in the plane, have full fuel, and are flying out of an airstrip at altitude.

 

[DandyDon]

There is no reason to remove the valves. Before the TSA finally published rules for airline travel on ponies, I drained my 19 cf pony but did not remove the valve for flights - only started when the rule went into effect.

I do now remove the valve and cover the neck with tape and wrap the valve in bubble wrap for my pony, but I would not do it on an o2 clean tank. :11:

 

[Saltwater Junky]

Private pilot? Your buddy or for hire.. either I think it's the pilot's decision. I haven't heard of any law regarding the transport of air tanks in a private plane. The main concern will be their storage and weight & placement vs. the planes load capacity and center of gravity.

 

[miketsp]

As was mentioned, pressurised gas cylinders are carried all the time on planes.

The reason civil commercial flights want the cylinder open is to be able to check that the cylinder isn't packed with high explosives.

For a 200 bar tank it's hardly relevant if the external pressure is 1ATM or 0.3ATM.

 

[String]

Surely there wont be any problem even if full safety wise - even if you took it into low earth orbit its only 1 bar / 15psi lower than its normally at and given the tank contains 200x that pressure 1 atmosphere is neither here nor there.

 

[Rick Murchison]

My only concern with 130's would be weight & balance. A 172 ain't a pickup
Make absolutely sure the tanks cannot shift (consider extreme maneuvers in rough air - they need to be tied down so that they can't move even at negative g) - there have been some very nasty mishaps over the years with shifting loads in 172's. One other concern may be load distribution on the cargo deck. Because the tanks are round, weight isn't distributed very well - you might consider a simple load distribution system like a piece of ½" plywood under the tanks.
Rick

 

[DennisW]

What Rick said. Just make sure your weight and balance are ok and the tanks are strapped down really good. I've carried tanks in my Cardinal several times.

 

[DA Aquamaster]

We used to fly to tech courses and other destinations, although we did it in a Twin Commanche or a Seneca, not the worlds best load haulers but better than a C-172.

Carrying compressed gasses in flight is not a safety issue per se and does not violate any FAA regs, as long as the pilot is aware of it. The practical safety issue revolves around having large heavy objects in the cabin where they could shift or come loose in a crash or emergency landing.

At a minimum you will want to strap them down (not always easy in a C-172 that was not really designed for cargo, and where double 130's would be both hard to get into the baggage compartment and would cause CG issues if you got them there). On option is to secure them with a suitably attached cargo net.

Still, my preference has always been to rent back gas tanks at the destination rather than push the gross weight and CG limits trying to take my back gas tanks with me. AL 40 deco bottles are harder to find but are travel freindly as they are neither bulky or all that heavy so taking your own makes sense . Stage bottles are easy to convert from rental AL 80's on site and all you need to take along are the stage straps and a screwdriver. Rental doubles are available more places than you'd think. Worst case, you end up using travel bands on rented AL 80's that you use as independent doubles with an 8 lb V-weight to offset the bouyancy of the tanks.

As bad as that sounds, it is better than trying to shoe horn two divers and their tech gear into a C-172 with 4 hours of fuel. A single tech diver is do-able in a 172, otherwise you need a bigger plane, maybe a Cherokee 6/Lance or a C-206.