Bad experience on my first dive with strong current

[time2sail]

IMHO a hot drop on the Duane requires good viz and experienced divers (in good conditions). In pour conditions, it is too risky for most Largo Ops.
There is a busy, shallow channel less than 1000yds North of the Duane, if you miss the wreck, you'll drift right into it and that tends to make the Largo Ops very nervous - not to mention that you will be out of the "safety" range of the dive flag unless you deploy your sausage as soon as you realize you missed the wreck or get separated from the person carrying the flag (which in that current, is another "no fun" factor. I always prefer a hot drop rather than a descent line, but most of the ops in this area do not like the additional risk factor.

 

[scubadada]

Many of us have become experienced and comfortable with the dive protocols in SE Florida. As per @time2sail, we need to be aware and appreciate that protocol may be different in other areas.

 

[John C. Ratliff]

Under heavy exertion, does the increased dead space from the snorkel contribute to early fatigue?

Under heavy exertion the dead air space can cause a problem, esp cially if it is a small person using a large-bore, long snorkel. The EU has standards about this, which David Richie Wilson has written about in the Vintage Scuba forum here.

But there is another potential for causing respiratory fatigue, and that has to do with snorkel design. There are a lot of "dry" snorkels which use various engineering designs to ensure that the snorkel stays dry in chop conditions. Some, but not all, of these designs cause increased breathing resistance. If, when you try a "dry" snorkel, you notice unusual noise when breathing through the snorkel, chances are that it is purposely increasing breathing resistance by obstructing the air pathway as you breath. What this does is prevent water from going directly down the snorkel tube. In addition, the increased pressure (breathing resistance) can purge water from the water trap at the bottom of the snorkel out the mushroom non-retipurn valve. If, when you blow out hard, bubbles are noticed coming out of the water purge valve, your snorkel is causing at least a one nice water pressure increase in breathing resistance. This is about twice the breathing resistance of a well-tuned single hose high-performance regulator.

The old-style J-snorkel, with no "bells and whistles," is a good choice for low breathing resistance. I have used this style in heavy waves, and even under the rotor wash from helicopters.

There are some snorkels which incorporate a design which makes the snorkel "dry" without increasing breathing resistance. I have three different designs that I have used for decades which are well-designed, pretty much preclude water, all while not increasing breathing resistance.

SeaRat

 

[Diving Dubai]

Many of us have become experienced and comfortable with the dive protocols in SE Florida. As per @time2sail, we need to be aware and appreciate that protocol may be different in other areas.

I've followed the comments about entry methods with some interest. There is always the possibility to pick up new ideas or tips.

I do laugh at the term "Hot drop" - It coungers up connotations of Special Forces Wanna be's. However I digress.

I can see both sides here, given I often dive wrecks (Not as often as those in SE FL), Sometime with experienced divers, sometimes guiding. I'm also qualified to Helm (drive) the boats and conduct drop offs and pick ups - and often do

When guiding a "gaggle", one needs to be mindful of their actual experience and confidence level (rather that the level they try to portray)

Even a small surface current and a bit of a chop, can overwhelm newer divers, it's just additional things on top of them getting themselves comfortable when they first splash. Having a line for these people is a double edged sword. On one hand a physical line gises reassurance, and something to hang onto and use to assist (given they often haven't perfected their finning) On the other hand, if the line is being taken by the current, they are forced to work harder pulling themselves along the surface and then diagonally down a line always into current.

This then causes a vicious circle of higher air consumption and the diver being pulled further out of their comfort zone.

But it is a sure way to keep a group together, and it does reduce the strain on the guide especially on the ascent or SS where a great many divers simply can't hold a stop in close proximity to a line, and feel the need to have physical contact (creating a circus)

For experienced divers, we do things differently (given few wrecks have mooring buoys) We use a compensated shot line.

Basically this is a weighted line with a buoy - however the free end of the line goes through the buoy and is attached to a weight, thus keeping the shot line straight (ish). We locate the wreck and toss in the shot, the most experienced pair go down and (hopefully) hit the wreck or move the shot to the wreck.

In this case the boat is always free. Our boats are configured with side ladders , entry is either back roll or giant stride, so we can position and hold the boat with the props away from the divers.

I'm not a fan of the Neg entry "meet me at the bottom method" We prefer (insist) that a bubble check is carried out at 6m/20' which also identifies if anyone is having trouble equalising. Having a straight shot assists with this. The shot is just a reference not an ascent/ descent line.

At the end of the dive, people either ascend alongside and shoot their bags (dsmb) or the shoot from the bottom if there is a current. In the case of the latter , the boat watches the bags on the surface and positions itself for pick ups. With up to 10 divers in the water, this isn't onerious nor does anyone get lost even with surface current.

Here of course we don't have to contend with "diver below buoys" but you do (on popular sites) need to be aware of other boats.

Anyway, just a perspective on how we approach the scenario over here

 

[scubadada]

Hi @Diving Dubai

In the Keys, the wrecks have permanent buoys. The Spiegel grove has 8! My favorite is the port superstructure aft ball. The Duane, discussed by the OP, generally has 2, there has occasionally been a 3rd off the stack. Operators here use the mooring lines for descent and ascent. As discussed, this is either when moored to the ball or with a hot drop to the ball. Also, as discussed, hot drops directly to these wrecks are hardly, if ever ever done

I am only intimately familiar with SE Florida diving done in Boynton Beach, West Palm, and Jupiter. None of the wrecks have buoys. In Jupiter and West Palm the wrecks are generally done by hot drop directly. These dives are often a drift including several wrecks and/or other structures. I have never seen a shot line used in Florida. The only one I've used was to dive the Hogan off San Diego. I would imagine that the currents present at the wrecks in Boynton Beach might render a shot line useless by pulling the weight from the pressure on the ball or balls. At these wrecks, a temporary ball is swum down and tied off. Access is then by hot drop to the ball or direct drop to the wreck. Especially if there is brisk current, direct drops are done by divers with prior experience and acceptable skills.