What if...? Dive Planning & Trust Me Dives

[MRadke]

Tabletop scenarios are all well and good, but how about a diagram to go along with it. From your description, superstructure affords some measure of protection to 65 feet. Also, what direction is the wreck lying in relation to the current. Assuming that I can get to the leeward side, I can use the hull for protection.

 

[Jax]

:dropmouth: :nailbiter: :sos:

Ditto . . .


Besides detuning the reg if it is adjustable, is it possible to cover your reg with your hand, or a hood, or something so the water pressure cannot get to it?

How about dropping to the deck and swimming behind structure to block the current?

What about tying off the reel to the structure and using it as an ascent line, keeping your face out of the current?

The problem with letting go and deploying the DSMB is (1) does the crew know what to look for? (2) Is the SMB large enough to be worthwhile? (3) it sounds the absolute last thing one would do, and the most dangerous.

 

[Cave Diver]

Sounds like a dive I did in the Channel Islands last year ... do Florida dive ops really take new divers out to dive sites like that?

... Bob (Grateful Diver)

I've done dives on both the Oriskany and the Spiegal where there was a ripping current and there were divers on the boat with only OW certs. Whether that's a fluke or common I can't say.

 

[Cave Diver]

Tabletop scenarios are all well and good, but how about a diagram to go along with it. From your description, superstructure affords some measure of protection to 65 feet. Also, what direction is the wreck lying in relation to the current. Assuming that I can get to the leeward side, I can use the hull for protection.

This is the best I can find at the moment. Assume current is running bow to stern.

 

[flots am]

What about tying off the reel to the structure and using it as an ascent line, keeping your face out of the current?

That would work if you had enough line (like if you were carrying the 350' OMS reel).

With a 100' reel on a ~100' dive, you'll be flapping in the current like a flag when you run out of line somewhere around 50'. (actual depth depends on the current).

The problem with letting go and deploying the DSMB is (1) does the crew know what to look for? (2) Is the SMB large enough to be worthwhile? (3) it sounds the absolute last thing one would do, and the most dangerous.

You can personally take care of #1 and #2, which makes #3 a non-problem.

I handle it by walking up to the boat captain and saying "If you see a 9' Yellow SMB with my name on it drifting down current, I'd appreciate a pickup when you get a chance." It works nicely, and believe it or not, the boat crew appreciates it because it makes the pickup a non-event.

A little prep work takes care of a lot of problems. I'd never do a potentially high-current wreck without a big enough reel and a big SMB with a finger spool.

This comes back to planning for how to handle it when "the brown stuff" hits the fan, before ever getting into the water. Most emergencies can be turned into interesting dinner conversation with a minimal amount of effort before the dive.

flots.

 

[Cave Diver]

Shoot the DSMB from depth and start ascending diagonally to boat across the current such that as I'm blown from the wreck the boat can see me but I'm still trying to move in the correct direction.

In that kind of current, your DSMB will never reach the surface from depth. If it does, then it's going to pull you up with it and will act as a sail and take you for a ride.

Diagonal movement should help reduce chances of freeflow, but wouldn't just looking down or turning around and "swimming backwards" with occasional glances for direction correction do the same thing?

Your first two options may help. I'm not sure what the ability to swim backwards in that sort of current would be, but I'd suspect it to be highly inefficient.

Ditto . . .
Besides detuning the reg if it is adjustable, is it possible to cover your reg with your hand, or a hood, or something so the water pressure cannot get to it?

That could possibly help, but may not be your best option.

How about dropping to the deck and swimming behind structure to block the current?

Also an option, but keep in mind your depth, time, gas and distance to travel. Max depth is currently 90' Most people will dive slightly above a wreck, rather than right on the deck. So you could safely assume dropping to the deck would put you in the 100' range.

What about tying off the reel to the structure and using it as an ascent line, keeping your face out of the current?

In heavy current, you won't have enough scope to reach the surface. Also, you'd be in danger of the line breaking under the strain. You could find yourself drifting and still at 50' or so with no line left to deploy a bag or worse, with the loose line tangled all around you.

The problem with letting go and deploying the DSMB is (1) does the crew know what to look for? (2) Is the SMB large enough to be worthwhile? (3) it sounds the absolute last thing one would do, and the most dangerous.

1) Crews would likely be familiar with DSMB.
2) Depends. What do you carry?
3) I'm sure there are worse options.

That would work if you had enough line (like if you were carrying the 350' OMS reel).

With a 100' reel on a ~100' dive, you'll be flapping in the current like a flag when you run out of line somewhere around 50'. (actual depth depends on the current).

You can personally take care of #1 and #2, which makes #3 a non-problem.

I handle it by walking up to the boat captain and say "If you see a 9' Yellow SMB with my name on it drifting down current, I'd appreciate a pickup when you get a chance."

A little prep work takes care of a lot of problems. I'd never do a potentially high-current wreck without a big enough reel and a big SMB with a finger spool.

This comes back to planning for how to handle it when "the brown stuff" hits the fan, before ever getting into the water. Most emergencies can be turned into interesting dinner conversation with a minimal amount of effort before the dive.

flots.

Correct and all good points. But as they say, hindsight is 20/20

 

[fjpatrum]

Ditto . . .


Besides detuning the reg if it is adjustable, is it possible to cover your reg with your hand, or a hood, or something so the water pressure cannot get to it?

How about dropping to the deck and swimming behind structure to block the current?

What about tying off the reel to the structure and using it as an ascent line, keeping your face out of the current?

The problem with letting go and deploying the DSMB is (1) does the crew know what to look for? (2) Is the SMB large enough to be worthwhile? (3) it sounds the absolute last thing one would do, and the most dangerous.

I would have the conversation about the DSMB with the crew before ever doing a drift or high current dive, personally. I haven't ever deployed my SMB yet, but it's a 6 footer, with both orange and yellow colors and a "reflective" patch too. I'm not sure why you think it would be the most dangerous. The SMB won't cause you to be pulled more by the current than you would otherwise since it's going to show significantly less surface area for drag than you would as a diver. Am I not considering something?

Thanks for the idea about staying behind/below the structure of the wreck though, I hadn't thought about that. With 1800 PSI in an AL80 I think one should be able to last a few minutes at ~60 FSW and still have some spare gas for a safe ascent.

 

[MRadke]

Well, swimming into the current is useless. I've done a similiar dive on C-58 in Cancun, where there always seems to be a ripping current. The regulator is the easiest, simply protect the purge valve. The first option to get back to the mooring line would be to stay as tight to the boat as possible, pulling oneself along by hand, thereby conserving air. If it were evident that plan A wouldn't get me where I needed to be, I'd shelter along the wreck until I got to the highest point and begin ascending. The dsmb is a problem because if deployed too soon, it will act as a sail and carry me further away from the dive boat. I also don't see it as a viable ascent line in current because it is too fine to hang on to. In Cancun the ascent line was an 1 1/2" rope that we flapped off of like a flag. I'd wait to deploy the dsmb until my safety stop, knowing that we have a smart captain that will come to pick me up if I stay calm and float with my rig on the surface.

 

[Cave Diver]

What about tying off the reel to the structure and using it as an ascent line, keeping your face out of the current?

Something else to keep in mind. Once you get to the top of your ascent line, you'll have no way to recover it. So now you need to either drop your reel or cut the line. If you choose to cut it, then you've got 100' of thin line flapping in the current on a wreck that may be difficult for another diver to see, posing an entanglement risk.

 

[Bubbletrubble]

@Cave Diver: Are there other moorings tied into the wreck? I've never dived the Spiegel Grove.

If there were a convenient mooring line nearby, my buddy and I could try to ascend using that. Although it wouldn't bring us directly back to our boat, it would get us to the surface without getting completely blown off the wreck. Once on the surface, we could inflate our signal tubes to get the crew's attention.