Deco vs. Drift?

[Spectre]

WreckWriter once bubbled...
See "The Last Dive" for Bernie Chowderry's tale of what can happen if one spends too much time looking for the line....

Exactly what I was thinking...

The longer at depth, the longer the obligation is going to be. Without an ascent device, nor training, he's better off ascending and looking at the same time... With 60 foot vis and 120 fsw, he should be able to see both the wreck and the boat when at 60 fsw.

However one must dive within ones limits. That guy definately wasn't... He probably should have stayed out of the water, or at least stuck near the guideline that the mate left...

 

[Jarhead]

Before I start, he was diving beyond his training.

1. 120fsw on air. NDL is 15 minutes (Navy tables)or 10 minutes (Navy table w/doppler). Gas "shouldn't" be a problem, but we don't know his SAC rate.

2. Vis is +/- 60 ft. He should be able see from one side of the wreck to the other and tell which is the long axis of the wreck. There is a mooring line at each end of the wreck. He should be able to find either line.

IMHO, The NDL may have panicked him.

Jarhead

 

[AquaTec]

I think he did the right thing by getting out of the water. a fee drift ascent is no big deal.
and his training says do not exceed your NDL, so he did the right thing by following his training.
also [if he was padi] they teach free ascents so again he was diving within his training.

yes he may have been pushing his own personal limits, but isn't that a main part of diving

i also don't see a problem doing a dive to 120 on air on a single tank, you are just going to be limited on your available time.

hopefully he gained some experience from this dive and will be better prepaired on his next dive

 

[Jarhead]

AquaTec once bubbled...
I think he did the right thing by getting out of the water. a fee drift ascent is no big deal.
and his training says do not exceed your NDL, so he did the right thing by following his training.
also [if he was padi] they teach free ascents so again he was diving within his training.

yes he may have been pushing his own personal limits, but isn't that a main part of diving

i also don't see a problem doing a dive to 120 on air on a single tank, you are just going to be limited on your available time.

hopefully he gained some experience from this dive and will be better prepaired on his next dive

120fsw, regardless of gas, was beyond his training. IMHO.

 

[AquaTec]

One guy on the boat, diving singles and air, had a problem on his dive. Apparently, he was away from the anchor line and not sure where it was when his computer showed him he had hit NDL. Rather than incur a deco obligation and search for the anchor line, he chose to make a free ascent from 120 fsw. I don't know if he completed his required safety stop or not (I didn't ask him), but he surfaced quite a ways from the boat and had to be helped back aboard.

here is the original post, it does not say anything about his training or experience or even his comfort level.

it simple says he was not in the area of the anchor line when he hit his NDL and as a result decide to make a direct ascent to the surface...

so what....

it may be that his experience and comfort level said no big deal i am at the end of my dive so i should surface.
his computer would have also informed him that after ascending 10 feet he would probably have another 10 minutes of NDL and after ascending 30 feet he probably had 30 minutes of NDL.

If I was him and the surface current demanded i find the line, i would have sufaced that 30 feet and then looked for the line as i continued to do a very slow ascent, as noted the current was very slight below the deco bar.

if i did not find it i would just surface per normal.

i am not sure what he did wrong other than display he is a new or inexperieneced diver by not knowing about Nitrox. he left the bottom when his computer told him to, he was not neer the anchor line so he did not waste time looking for it, and he ascended to the surface, plus performed his dive without inscedent.

some people beleive that you should never surface without a line, thats ok, but i would bet his training taught him how to do it without a line....lets not be to critical of a diver who is inexperienced just because he chose not to go into deco looking for a line that he may or may not have needed.

it does sound like he arived on the boat under his own power, so the current could not have been to strong or he could not have swam against it. and maybe he even made an angled ascent against the current to put him closer to the boat upon surfacing

he will have learned form this dive and add to his experience tool box

 

[WreckWriter]

AquaTec once bubbled...
I think he did the right thing by getting out of the water. a fee drift ascent is no big deal.
and his training says do not exceed your NDL, so he did the right thing by following his training.
also [if he was padi] they teach free ascents so again he was diving within his training.

yes he may have been pushing his own personal limits, but isn't that a main part of diving

i also don't see a problem doing a dive to 120 on air on a single tank, you are just going to be limited on your available time.

hopefully he gained some experience from this dive and will be better prepaired on his next dive

You're right, the ascent itself was no biggie, except when you factor in the current and the moored boat. That makes it dangerous.

And yes, pushing one's own envelope IS a big part of diving, mine anyway.

Tom

 

[AquaTec]

well if he swam back to the boat under his own power then the current could not have been to strong.

second i would not mind the boat moored if i can swim against the current.