Flying after diving question.

Myself and two other divers want to fly from Fort Lauderdale in a private small plane (owned by one of the divers) to Key West and dive the Vandenburg.If we were to fly back to Fort Lauderdale at 2,000ft would we still have to abide by the "no-fly" time on our computers. Or is there a "no fly" table we can use so we dont have to wait 12 hours to fly back.
thanks
Graham

If you're flying in an unpressurised plane, then anything over an absolute maximum of 1000ft is out within a MINIMUM of 12 hours after diving - definitely longer for multiple dives or deco diving. Anywhere above 1000ft, ambient atmospheric pressure is too low for the assumptions your dive computer or tables are making about safe nitrogen loads to still hold true.

Bear in mind that 1000ft and 12 hours are theoretical limits, too: lower and longer give you more of a safety margin.

This DAN Divers Alert Network might help.

While I agree that avoiding altitude after diving is a good idea, I am not sure it is mandatory to stay under 1000 feet for 12 hours after diving. Many of my dive buddies and I live at 1100-1300 feet and dive in the ocean regularly. We drive home right after diving. Time between ending the dive and arriving home is usually about an hour. There is absolutely no talk in our neck of California of not going home right after a dive. Usually we don't push the NDL's, especially when shore diving, but if we go to wreck alley, we might get pretty close.

I would think it would be a good idea to stay FAR away from NDL's if planning a moderate altitude trip within a few hours of diving and certainly to limit repetitive dives. Nitrox is also a good idea if you are qualified.

Now, I am not part of DAN or a qualified scientist, so please don't fly just because I said I drive home after diving. However, IF you can really guarantee the plane will stay under 2000 feet and if you stay several pressure groups away from the NDL's, your risk may not be that high. Of course, your risk is not zero either.

People do dive at altitude, with base altitudes of over 2000 feet. They just have to adjust dive times at depth.

Question for the more experienced - Can oceanpro simply calculate and dive NDL's based on a 2000 foot base altitude and use those during the ocean dives?

Yes, there is a table that clearly shows minimum times to ascend to particular altitudes depending on your repetitive dive group. No, I'm not going to tell you where to find it. It's in the public domain, though.

drive is only like 4 hrs and you could stop off and dive along the way, but there more than likely are tables they base it on. You could always schedule your dives to get you a decent amount of time between flying, like flying out in the morning since most people are usually in from diving in early afternoon. then dive the vandy and run around on KW for the rest of the day and fly out next am

oceanpro4:

Myself and two other divers want to fly from Fort Lauderdale in a private small plane (owned by one of the divers) to Key West and dive the Vandenburg.If we were to fly back to Fort Lauderdale at 2,000ft would we still have to abide by the "no-fly" time on our computers. Or is there a "no fly" table we can use so we dont have to wait 12 hours to fly back.
thanks
Graham

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It is and isn't the same... We dove in Saba this past year. Diving is of course at sea level and everything else is up the volcano. We stayed at Windward Side elv. 1200'. There has never been a reported case of DCS. (NOTE: Your experience may be different...)

Here is Sea Saba's web page concerning DAN's testing in 1990

Sea Saba

Here is the DAN link to the testing result (also found on that Sea Saba page)

DAN's Testing Results

Everyone has to assess their own risk when deciding to dive then fly. I know I had a friend in the 80's who was a diver and a small engine aircraft pilot. He got bent once without flying and later got bent a second time flying within 12 hours of diving and flying just under 4000'

oceanpro4:

Myself and two other divers want to fly from Fort Lauderdale in a private small plane (owned by one of the divers) to Key West and dive the Vandenburg.If we were to fly back to Fort Lauderdale at 2,000ft would we still have to abide by the "no-fly" time on our computers. Or is there a "no fly" table we can use so we dont have to wait 12 hours to fly back.
thanks
Graham

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You do not have to wait 12 hours, that idea is based on an ascent to 8,000 feet. Plan your dives as though they were conducted at 2,000 feet to begin with (you'll have to use altitude tables). You could also use the old Navy Group C rule (which is good to 8,000 feet), by checking the scrolling No-D limits against the Adjusted No-D limits for each depth for a Group C diver on the table and being as conservative as possible.

GrimSleeper:

If you're flying in an unpressurised plane, then anything over an absolute maximum of 1000ft is out within a MINIMUM of 12 hours after diving - definitely longer for multiple dives or deco diving. Anywhere above 1000ft, ambient atmospheric pressure is too low for the assumptions your dive computer or tables are making about safe nitrogen loads to still hold true.

Bear in mind that 1000ft and 12 hours are theoretical limits, too: lower and longer give you more of a safety margin.

This DAN Divers Alert Network might help.

Click to expand...

If what you mean is that sea level assumptions no longer hold, you are correct. If what you mean is that you can't use a computers "time to fly" calculation,then you are wrong since that is predicated on an 8,000 foot ascent and thus is way conservative.

oceanpro4:

Myself and two other divers want to fly from Fort Lauderdale in a private small plane (owned by one of the divers) to Key West and dive the Vandenburg.If we were to fly back to Fort Lauderdale at 2,000ft would we still have to abide by the "no-fly" time on our computers. Or is there a "no fly" table we can use so we dont have to wait 12 hours to fly back.
thanks
Graham

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The pilot oughta check into this too. There was a post here recently with some FAA regs (I think) that a pilot is not ALLOWED to fly within a certain period of time after diving.

AzAtty:

Yes, there is a table that clearly shows minimum times to ascend to particular altitudes depending on your repetitive dive group. No, I'm not going to tell you where to find it. It's in the public domain, though.

Click to expand...

RJP:

The pilot oughta check into this too. There was a post here recently with some FAA regs (I think) that a pilot is not ALLOWED to fly within a certain period of time after diving.

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I think that was only for commercial flights...? I stand corrected.