Rescue procedure if diver blown off wreck?

[Kendall Raine]

This whole discussion brings up the concept of different diving models. On the one hand there is the team concept. At the other extreme is the pick-up model. In the middle is how most LoBs operate.

In team diving the boat is part of the team and everyone is on the same song sheet. The dive plan is developed with this in mind and everyone plays their part-captain, crew, bottom divers/teams and support divers (if any). The plan considers surface conditions and possible sea state changes over the course of the dive, boat traffic, current, team dive plans as well as contingencies (e.g. getting blown off). The higher the complexity of the dive, the closer the tolerances need to be. The plan considers proximity/pre-notification of USCG/SAR assets, proximity to chamber resources, etc. Contingencies aren't left entirely to the boat captain to think through and manage (or not), they are developed with the dive team and known/embraced by everyone involved. Obviously this system works best in smaller groups of competent/dedicated divers committed to and knowledgeable of team concept discipline/procedures and willing to put in the time and money to achieve it. This is how a lot of expedition diving is done-necessitated by the added complexities of those types of dives. I think this is what Nick was getting at, but it is much more involved than simply whether the boat is operating live or static. Besides, there are times when planned live boating/drifting deco is problematic (e.g. shipping lanes). Adjusting the protocol for site conditions (up to and including not doing the dive at all) is inherent in the team concept.

This unified team concept is foreign/contradictory to pick-up dives off open (aka "cattle") boats-the way a lot of diving is done in Florida/California/New York/New Jersey. In that scenario captains typically regard themselves as transportation. They often don't know the divers, their dive plans, capabilities or contingency plans and, frankly, don't ask. Achieving true team execution among a group of pick up divers for a day/open boat is structurally not workable. I don't see it as prima facie evidence of a captain's laziness/incompetence per se (like not having a night watch), but a symptom of a business model driven by volume, speed and price. Site selection is probably influenced by the composition of the divers (classes/hunters/novices/experienced (whatever that means)), but that's about it. Low incident rates are more a function of the low impact/simplicity of the diving rather than any planning worthy of the name. Divers are expected to conform to the boat's procedures, however loosely thought through and articulated those might be. Maybe there is a chase boat (RIB)/underwater recall systems, tag lines, etc.-often times not. But the notion of a unified team operation is unknown/anathema. Divers typically dive in buddy teams (maybe?) with little to no regard/consciousness of what other dive teams are doing. Divers have been taught this is the way diving is done and think that's the end of the story. It doesn't need to be that way. Unfortunately, it also means divers need to take responsibility themselves (including skill development) to organize their diving and work through contingencies (blow off, lost buddy, aborted dives, etc)-something for which they are generally un/under prepared (inherent in high velocity low price/content instruction). The idea that a diver blown off a wreck by current needs "rescue" (the OP's scenario) versus "retrieval" is admission of utter failure of even the most basic form of self-sufficiency/dive planning top to bottom. In a static (non-live boat) boat scenario, a blow off/drifting ascent should be assumed and planned for (e.g. chase boat, DSMBs, etc), not dismissed by a captain's admonition to "come up the anchor line or else." If it can't be factored into the plan (at least as a contingency to the plan) then the dive shouldn't happen. Just common sense.

LoBs deal with this reality by using guides/small dive groups/live boat(s) operating from motherships. This is not team diving, but rather a band aid stuck on a pick up dive model.

 

[Gelirfella]

I’d never even considered that the boat is part of the team in a team diving model. That’s a great way to think about it. Clearly not operational in most contexts. It’s a great way of framing it though. I had not considered that the concept of true surface support could really extend beyond the scope of the big expedition dives I read about.

 

[johndiver999]

This skipper's comment may have been in jest or intended to scare you and your fellow divers into staying on the down line, but it could also create more problems when things start to go wrong. A diver with a minor problem that could be resolved easily on a drifting ascent could easily cascade into panic if they're too stressed by losing the line and fighting current to get back to it. Stuff usually gets wierder from there.

I'm a big fan of hot drops in stronger current, but that method requires set-up skills on the captain's part and often a negative entry + quick descent by the divers. Other factors on the diver side can complicate this (trouble equalizing quickly, type of gear used, etc.), requiring longer up-current lead distance on the drop and better "Kentucky windage" estimation by the captain.

Combinations of these hot drop factors not lining up are what cause divers to miss wrecks on hot drops. So, some operators keep using the down-line method in strong current to mitigate known issues. These can include: a mix of diver skill levels, lack of experience with hot drops, lack of local condition knowledge, fear of missing the wreck (FOMO-W?), and others. A tie-in has the advantage of a direct connection to the wreck (tougher to miss), but the disadvantages and dilemmas noted in the posts above plus it limits the ability of the dive boat to assist anyone blown off the wreck. Hot tip: if your skipper plans to do a stern tie-in on a high current day, things may even get more interesting.

With either method, all divers should carry a DSMB and long enough spool/reel to account for depth + current. High school trig finally pays off to calculate how much line you'd need at 100' deep with a current pulling your line at 45 degrees off vertical. I like using [2 x max expected depth] as a rule of thumb, because it allows shooting the bag immediately and not worrying about getting yanked up by the line. The closer you can send a DSMB to the boat, the better chance the crew has of seeing it.

The skipper's comment quoted above is problematic, because shooting a bag is the simplest way to recover divers blown off a wreck. This captain is effectively eliminating that option in an inexperienced diver's mind. However unfortunate, my response to this attitude is to be ready to shoot a bag from depth and carry a PLB and/or InReach device on these types of dives. I also let the crew and other folks on the boat know I'm carrying electronics, so we can group up if something happens and collectively have better odds while drifting.

I'm curious - do any agencies cover this type of practical stuff in rescue, wreck, or boat diving courses? I see lots of folks diving near rec limits here in south Florida with no clue about how most of this works.

Lance

I agree with most all of this, but it is worth mentioning that a hot drop in a screaming current to a wreck in bad visibility is a very bad idea. Extremely dangerous in that divers can be impaled on superstructure or blown into entanglements with no warning or meaningful ability to evade. Pulling down a line in screaming current ain't fun, but if you can't see a considerable distance, drifting into a wreck is not a safe option. This may be one additional reason why drifting into wrecks is not used in some areas.

 

[Edward3c]

I’d never even considered that the boat is part of the team in a team diving model. That’s a great way to think about it. Clearly not operational in most contexts. It’s a great way of framing it though. I had not considered that the concept of true surface support could really extend beyond the scope of the big expedition dives I read about.

It’s built into BSAC Advanced Diver training, handling and navigating boats is part of the course. Along with arranging and managing a multi day dive trip to unknown dive sites.

 

[Doc Harry]

When we were brand new divers, my wife and dove a deep wreck in the Keys. It was fairly dark from the clouds, raining hard, and there were high winds with good sized waves. The current was strong and the visibility was 30 feet. When we got to the wreck at the bottom of the mooring line (100 feet), I realized that we didn't have a plan for what to do if one of us got blown off the wreck. I called the dive right then and there, and we went back to the surface.

Now I know what to do.

Stick with your buddy. Shoot an SMB right away.

If another group gets blown off the wreck, they should follow their plan.
But I am not going to try to rescue them.

 

[MacDuyver]

This is a general hypothetical question. Let’s say you are at depth on a wreck with a decent current. You are personally able to swim against it but it’s definitely hard work. You finish your dive (let’s say you thumb it because of the current). You and your buddy make it back to the upline. You notice another team has been blown off the wreck and are struggling to make it back to the upline. One diver is okish making small headway but seems to be flagging. The other is farther out and not making headway.

What’s the appropriate procedure? Let’s say you have plenty of gas. Depth is 110, you’re on 28% and have only been down 10 minutes in your twinset.

I was floating in my mind that you might consider tying off to the upline (using your Smb spool, assuming you don’t have a true reel) and swimming out to both divers assuming they are reachable and putting them on the line. You already know you can swim against the current so not a huge risk of not getting back and you are on a line. But wondering what the likelihood of breaking that line is with 3 divers in current/are you just creating an entanglement hazard?

Maybe the best plan is just to keep an eye on them as you surface and alert the captain? Do you fly an Smb just so the captain is alerted to a potential problem and might consider dropping a diver to check it out?

This is actually a very realistic non-hypothetical scenario if you dive Samaesarn in eastern Thailand. It is one of my favorite dive areas ever. The current absolutely rips in those islands though. If you are blown off the wreck, you very well might not be able to fin back to it.

The procedure with the several charters I’ve dove with there is:
-hold onto the line as you descend and ascend gauging current strength as you go.

- before the dive they discuss the wreck and where the current shadow is (the underwater leeward side of the wreck is very noticeably easier to stay close to). Brief before the dive always involves guidance from the DM on how to not get swept away if the current is strong at depth (it rips but not always) and how to navigate the wreck so you stay in the shadow of the current. They also cover the “drift” plan in case it happens.

- dive buddies always stay within arms reach shoulder to shoulder when outside the wrecks. You enter and exit wrecks in the shadow of the current prepared to hold on while your buddy is entering/exiting in case something changes.

- if one buddy goes, both of you go

- once you realize you’re getting blown off the wreck, descend to the bottom or to your MOD, whichever comes first and try to escape the current to head back to the wreck.

- If you cannot overcome the current at depth, continue the drift and begin surfacing together immediately.

- shoot an SMB from depth so the boat can track your movement (a 100’ SMB line is not unheard of in the area where the wrecks are between 60 and 90ft, with many areas where the bottom can be 100ish)

- there’s no telling how far off the boat is at this point, so do your safety stop if there is no immediate threat to life.

- the good DMs check for secondary signaling (mirror, whistle etc) before the dive. Not all do, but if you’re diving open ocean you really ought to bring it upon yourself to have one securely attached to your gear. Or two. I have a red/silver mirror tied to the D-Ring on one shoulder strap, and a wind storm whistle zip tied to my power inflator

- in Samaesarn, the current flows to open ocean. in an emergency like that, any boat you can get the attention of is the right boat to get out of the water onto. Royal Thai Navy will help get you back to shore if that boat can’t

We did one during my Wreck course (planned deliberately ahead of time as a drift off of the wreck). man. There are definitely currents there that you have no chance of escaping. Always have a contingency plan and rehearse it a few times verbally before you go.

 

[mdwalter]

What’s the appropriate procedure? Let’s say you have plenty of gas. Depth is 110, you’re on 28% and have only been down 10 minutes in your twinset.

Stay with your buddy on the up line. Since you have plenty of time (gas) remaining, you can stay down on level with the team fighting their way toward you and "coach" them on some techniques that could help them (which should ideally have been discussed on the boat before the dive).

For example, if the up line is tied into the wreck and the divers are being blown away from the tie-in, there is a good chance the scope of the up line puts it directly above the struggling divers, so swimming into the current while also ascending can get the divers closer to the line as they ascend. This effect can also be accentuated by your going up the line past where the struggling team is, getting yourself a bit negative, and bringing the line down closer to them to aid in the previous technique.

Another example would be to signal the struggling team to descend and get behind parts of the wreck where they will have a bit less current to fight and where they may also be able to pull along the wreck while finning to make better progress. Again, you could assist by getting negative and bringing the bottom part of the up line along the wreck toward them so they can get to it sooner.

Note that in all these scenarios you and your buddy never leave the up line, but are actively communicating to the other team helpful suggestions and actively doing things to help them out without putting yourselves at higher risk. And, as many others have said, it doesn't hurt to pop up a marker at the early signs of a problem to let the boat know that something is happening down here.

I was floating in my mind that you might consider tying off to the upline (using your Smb spool, assuming you don’t have a true reel) and swimming out to both divers assuming they are reachable and putting them on the line. You already know you can swim against the current so not a huge risk of not getting back and you are on a line. But wondering what the likelihood of breaking that line is with 3 divers in current/are you just creating an entanglement hazard?

No you should not swim out on a string, there is a significant chance of breakage, and break or not it is a significant entanglement hazard.

Maybe the best plan is just to keep an eye on them as you surface and alert the captain? Do you fly an Smb just so the captain is alerted to a potential problem and might consider dropping a diver to check it out?

Of course, if your team is low on gas or hitting deco that will cause you to be low on gas to do a safe exit, the other team is on their own and you need to just go up at that point.