EAN versus "no-Fly" delay

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Can you post a link? All the links that I have found want a credit card to look at these tables.
The owner has constrained BSAC from making table information available electronically. Any you've found are either to purchase hard copy of their 'hacked' copies. This is the only official place they can be purchases
 
Simple fact is that by the time you get out of the water, back to your hotel, check out, get to the airport 2 hours before boarding, and assume that the plane will not lose pressure, you are very unlikely to have a problem diving and flying. Tbone will be proven correct most of the time, with or without using 8000 foot tables.
 
Simple fact is that by the time you get out of the water, back to your hotel, check out, get to the airport 2 hours before boarding, and assume that the plane will not lose pressure, you are very unlikely to have a problem diving and flying. Tbone will be proven correct most of the time, with or without using 8000 foot tables.

Agreed........I used tbone's theory (8,000 ft. dive plan) for every max NDL dive in 10 ft. increments from 10 ft. to 100 ft. The greatest "time to fly" was 4:22 and that was an NDL dive to 30 or 40 ft. Diving to NDL at 90 ft. using the 8,000 ft. altitude charts and it seems as if you can go directly from the water to the airplane. Very interesting.

Of course, this was all using USN tables. YMMV with any other agency.
 
Agreed........I used tbone's theory (8,000 ft. dive plan) for every max NDL dive in 10 ft. increments from 10 ft. to 100 ft. The greatest "time to fly" was 4:22 and that was an NDL dive to 30 or 40 ft. Diving to NDL at 90 ft. using the 8,000 ft. altitude charts and it seems as if you can go directly from the water to the airplane. Very interesting.

Of course, this was all using USN tables. YMMV with any other agency.

Did you try comparing that with the scheme in section 9.14 on the diving manual?
 
Did you try comparing that with the scheme in section 9.14 on the diving manual?

That's exactly what I used.

Table 9-4. Sea Level Equivalent Depth (fsw). - used to determine equivalent depth of altitude dive.

Table 9-7. No-Decompression Limits and Repetitive Group Designators for No-Decompression Air Dives. - used to determine max NDL.

Table 9-6. Required Surface Interval Before Ascent to Altitude After Diving. - used to determine wait time before flying (assuming 8,000 ft. cabin altitude).
 
If your dives are time or gas limited, nitrox will reduce your residual nitrogen just like op is hoping. I know a lot of divers and only a few are surfacing due to ndl. I sure wish I was... large boats compound the problem by introducing 1 hr dive tI'm limits (if you're first off and last on).

So we get added safety.. you gas suppers may not, I guess.

I doubt think you can quantify no fly safety, but surely using nitrox will increase safety some if he's going to fly less than 24 hours after diving.
 
Agreed........I used tbone's theory (8,000 ft. dive plan) for every max NDL dive in 10 ft. increments from 10 ft. to 100 ft. The greatest "time to fly" was 4:22 and that was an NDL dive to 30 or 40 ft. Diving to NDL at 90 ft. using the 8,000 ft. altitude charts and it seems as if you can go directly from the water to the airplane. Very interesting.

Of course, this was all using USN tables. YMMV with any other agency.

That's exactly what I used.

Table 9-4. Sea Level Equivalent Depth (fsw). - used to determine equivalent depth of altitude dive.

Table 9-7. No-Decompression Limits and Repetitive Group Designators for No-Decompression Air Dives. - used to determine max NDL.

Table 9-6. Required Surface Interval Before Ascent to Altitude After Diving. - used to determine wait time before flying (assuming 8,000 ft. cabin altitude).

What were the rest of the no fly times? I assume that 4:22 is 4 hours and 22 minutes?
 
What were the rest of the no fly times? I assume that 4:22 is 4 hours and 22 minutes?

Yes, it is 4 hours and 22 minutes. However, I reviewed my chart today and discovered an error in reading/interpreting the tables. Essentially, 4:22 is the required surface interval after the dive for the diver to become a group C diver and hence require no wait to fly. The correct way to interpret Table 9-6 is to take the highest repetitive group designator from the last 24 hours - there is no allowance for surface interval. In the example cited, you would exit as a Group I. Table 9-6 would then require 12 hours and 44 minutes before ascent to 8000 ft. The other 'no fly' times would be: 50 ft. - 9:13, 60 & 70 ft. - 7:06, 80 ft. - 4:39, 90 ft. - 0:00, 100 ft. - 1:45.

I did the analysis again, but this time I calculated the dive as a repetitive dive starting as a Group G (see Table 9-5). Although I did get several dives that allowed me to go directly to the airplane cabin altitude of 8000 ft., the dive times were so short that it seemed to be a case of 'why bother'.

In any event, the USN has established a very good table that is very easy to use when trying to figure out how much surface interval is required before ascent to altitude after diving. As interesting as tbone's theory is, I could not validate it using any of the U.S. Navy's tables. Until we get a little more information, guess I'll just stick to what I know (trust me, that's not a lot).
 

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