Flight to Mainland from Cozumel, DCS risk?

[melfox26]

I'll be leaving for Coz in 2 weeks!!!!!!! Anyways, back to my question.

Has anyone taken the tour from Coz by plane to Chichen Itza? We're planning on going there the day before we leave Coz, after 5 days of diving with at least 12 dives spread over those 5 days. I'm assuming the plane won't be traveling as high as commercial aircraft going back to the states, so is there less of a DCS risk? It will be at least 18-20 hours after our last dives which I plan on asking the DM to stay shallow. Is there a significant risk of DCS? If there is, I'd probably take the ferry/bus to Chichen Itza, but it'd take all day.

I also have the option of diving Nitrox, which would help me, but my buddy is not Nitrox certified.

Thanks for your help,

Mel

 

[roakey]

I've flown 18-20 hours after diving and had no problems, but that's just me. And this was a lot of diving with long bottom times, approximately three and a half hours of bottom time at about 30' the day before flying (caving in Akumal), so that's a lot of slow tissue loading.

But again, that's me.

Also note that commercial airlines are pressurized to 8,000 feet, so commercial vs. small plane is a red herring.

But let me comment on something else you wrote:

It will be at least 18-20 hours after our last dives which I plan on asking the DM to stay shallow.

Unless the entire group on the boat is taking this plane ride and wants to stay shallow, is that a fair thing to ask of the dive master/operator? After all, assuming that your group does not make up the entire group on the boat, there are folks leaving every day from Cozumel. How would you like it if, on each of your five days someone was leaving the next day and "wanted to stay shallow?" You'd never get under 30' your entire week of diving and you'd be back here after your vacation complaining about the dive operation.

Sorry, I've been subject to a lot of "me first and only me" thinking in the last couple days and I'm getting tired of it.

If necessary don't dive the day before, or only do a morning dive on that day. Don't force the entire boat to kowtow to your desire to go on a sightseeing trip.

Roak

 

[melfox26]

if I wanted a basic scuba discussion, I'd post it in that forum.

Sorry, but I've been subject to a lot of "going beyond the question and overanalyzing evey sentence in someone's post" thinking in the last couple of days and I'm getting tired of it.

Mel

 

[jlyle]

IMHO, no need to worry. The plane to Chichen Itza from CZM is unpressurized and low flying. Many thousands of divers have taken the tour after multiple days of multiple dives. The DAN recommendation of 12+ hours before flying in a plane pressurized to 10,000 feet is a sound one. You will be well within the recommendations on this flight.

You can dive nitrox even if your buddy isn't. And, why not have him/her take the class while you are there?

 

[pipedope]

Is a subject with lots of different opinions. Ask 5 different sources and get 7 opinions.

From my reading of the DCI reports from DAN I find that the majority (i.e. nearly all) of DCI while flying incidents the diver was showing symptoms of DCI before getting on the plane.

18-20 hours is a good interval and as long as you are showing NO symptoms of DCI you should be fine.

If you ARE showing symptoms of DCI, activate EMS, call DAN, and get evaluation and treatment.

 

[DandyDon]

if I wanted a basic scuba discussion, I'd post it in that forum.

I thought that "roakey" had a good point. How are you going to get the Dive Guide to run shallow dives only for the whole group so you can stay shallow...? Not going to happen.

Diving Nitrox would give you a more shallow EAD, which would help. And you can still do that, even though your buddy is not serious enough about diving to be Nitrox certified. Or, he could do a Discover Nitrox.

Bottom line: No real worries. What "jlyle" and "pipedope" said...

 

[roakey]

if I wanted a basic scuba discussion, I'd post it in that forum.

Sorry, but I've been subject to a lot of "going beyond the question and overanalyzing evey sentence in someone's post" thinking in the last couple of days and I'm getting tired of it.

Mel

I guess a forehead-slapping epiphany was asking too much.

Roak

 

[aa777888]

IMHO, no need to worry. The plane to Chichen Itza from CZM is unpressurized and low flying.

Pressurized doesn't matter. How low are you talking about?

Mel: without someone posting for certain about the altitude, you at least have to assume that the cabin altitude of the short hop is going to be about the same as a long one (see below). Sorry, can't help with the 18-20 hours part of the question.

To amplify Roakey's comment about "commercial vs. small plane is a red herring.":

Don't know about Mexican reg's, but U.S. reg's allow civil flights below 10,000 feet to be conducted without supplemental oxygen for the duration, between 10 and 12K for 30 minutes without, and over 12K you must have supplemental oxygen. Of course, supplemental oxygen effectively means pressurization on any common commercial passenger aircraft. Approx. max. cabin altitude on a pressurized aircraft, as probably everyone here already knows, is 8,000'.

So they might operate at 10,000'. 10K doesn't look like much when you normally fly at 30K in commercial airliners. So just because it looks low out the window doesn't mean it is, diving-wise. It can be very difficult to judge your altitude by eye over unfamiliar terrain and it's darn near impossible over water, even if you are very experienced.

On the other hand, if you had a chance to chat with the pilot, or the plane was small enough so you could read the altimeter that would be a bonus.

Disclaimer: I have little diving experience and I didn't sleep at a Holiday Inn Express last night, but I do know a little about airplanes.

 

[jlyle]

I finally got the information back about the flights to Chichen Itza from CZM. The flights are at 6,000 feet altitude. Not as low as I thought!

 

[DocVikingo]

(nt)