What to do when your dive boat sinks?

[Steve_C]

Source? USCG is normally very conservative, in my experience.
Thank you, Mr. Armchair General, sir.

I used to have a 19 footer and had read up on what the numbers meant. Here is a recent document: I added the boldface. You can do a simple web search and find similar statements on many boating sites.

"There are a number of variables that boat manufacturers consider when determining the maximum person capacity that appears on your Capacity Plate.

One of those variables is the weight of each person.

Boat manufacturers typically use an average weight of about one hundred and fifty pounds per person to calculate maximum capacity. It can be a little more or a little less, but if some or all of your passengers weigh over one hundred fifty pounds, you may have to decrease the number of passengers you can safely take on board.

Remember, the maximum person capacity is a guideline that you have to adjust given the weight of your passengers and the other supplies you are taking on board.

If you are carrying heavy equipment, you may have to further reduce the number of passengers."

 

[MargaritaMike]

Thank you, Mr. Armchair General, sir.

Since it's maritime related shouldn't it be "Thank you, Mr. Armchair Admiral, sir."?

 

[Steve_C]

Source? USCG is normally very conservative, in my experience.
Thank you, Mr. Armchair General, sir.

RTFM

 

[GreyhoundsAreFast]

Boat manufacturers typically use an average weight of about one hundred and fifty pounds per person to calculate maximum capacity. It can be a little more or a little less, but if some or all of your passengers weigh over one hundred fifty pounds, you may have to decrease the number of passengers you can safely take on board.

Remember, the maximum person capacity is a guideline that you have to adjust given the weight of your passengers and the other supplies you are taking on board.

If you are carrying heavy equipment, you may have to further reduce the number of passengers."

I asked for a source but you didn’t really give one. At least not one that’s verifiable.

I just find it amusing that you truly believe that you can determine the root cause of a boating accident knowing only 1% of the details.

Since you seem to truly believe that this particular boat (which had < 1/3 of USCG’s recommended passengers aboard) had too much weight, I’ll refer you to “RTFM:” 230 Vantage Boat Model | Boston Whaler

Rated for ten passengers and 3000lbs. I’m not good at math but maybe you’ll be so kind as to extrapolate for us and advise the investigator of your findings.

 

[Steve_C]

I do not know the root cause. I do not know how rough that water was. I do not know how long the anchor line was. I may have misread it but the OP said there were 6 people in the boat at least 3 of which were divers. I still believe that over weighting may have been a contributing factor. The boat was over weighted according to the manual.

According to the manual you sent. The boat capacity is 3000 and that includes people, motor, and any gear. It says for passengers 10 persons or 1650 pounds so that is 165 pounds per person including gear. I do not know how heavy that engine is but according to the specs the weight of motor, fuel, and water is 1,550 lbs. That means all passengers, scuba gear, ice colors, etc has to be kept within the 1650 pounds.

So 6 adult males (assumption) plus scuba gear for at least 3 divers, plus any coolers etc will put them very close to 1650 if not over.

The manual clearly states Do not load to capacity in poor weather or rough water.

 

[CT-Rich]

I was thinking the same about weight, also. How a boat handles with the weight and gear for six divers is going to be a factor. 6 divers (165x 6=990 lbs), 6 weight belts and other kit (6x 30= 180 lbs) 12 tanks, Al 80, assuming 2 dives each (12x 35= 420 lbs). That’s 1590 lbs divers and gear alone, 1400 lbs if only a single tank. Weather and how the weight was distributed will also play a role. So I was thinking about overloading myself. Which whaler was it?

I’m glad no one was hurt, and I hope no kit was lost or any permanent damage. Just out of curiosity, when you realized she was flooding, did they consider getting underway again and heading in? The hull should be self draining as long as you are underway (if I remember correctly).

 

[Steve_C]

I
Rated for ten passengers and 3000lbs.

You have to understand what those numbers actually mean. This time I have quoted from the manual to show you what they mean.

 

[GreyhoundsAreFast]

I was thinking the same about weight, also. How a boat handles with the weight and gear for six divers is going to be a factor. 6 divers (165x 6=990 lbs), 6 weight belts and other kit (6x 30= 180 lbs) 12 tanks, Al 80, assuming 2 dives each (12x 35= 420 lbs). That’s 1590 lbs divers and gear alone, 1400 lbs if only a single tank. Weather and how the weight was distributed will also play a role. So I was thinking about overloading myself. Which whaler was it?

I’m glad no one was hurt, and I hope no kit was lost or any permanent damage. Just out of curiosity, when you realized she was flooding, did they consider getting underway again and heading in? The hull should be self draining as long as you are underway (if I remember correctly).

There were three divers in the water already. 1tank each, I assume nitrox.

 

[Steve_C]

"quote: The water was not entering the boat so much when they were skimming across it, but the boat must have sat lower in the choppy water once they were anchored."

I may be dense. If I am wrong I appreciate being shown why using facts. But I still have not seen a computation based on definitions from the owners manual to show that the boat was not over weighted for conditions on the way out and while anchoring and while divers are going into the water. Boats settle lower when they come off plane. Boats dip lower on the side where people exit. There also was some water entering when on plane. Saltwater is 8.6 lbs per gallon. Even as little as 10 gallons of salt water sloshing around is another 80 some pounds.

According to Archimedes how low a boat sits in the water is entirely dependent on the weight.

 

[Bowers]

I know im late to the party but heres my two cents.. The captain should be radioing a mayday call and you should be grabbing a life jacket. Yes i said life jacket not bcd, because a pfd rated for offshore use (lifejacket) is usually a bright color for rescuers to see from a distance and designed to keep your face out of the water even if you go unresponsive.