Horrifying new details emerge from dive boat crewmen...

Daily Mail UK ^ | 09/05/2019 | Lauren Fruen

[_Jim]

re: “ Hopefully there are tapes of both sides of the conversation, and if not, why not? “

Who sits around recording CH 16 marine (156.800 MHz) calls?

Coast guard could have had a ‘tape’ rolling ...

[livius]

I read that when the people on deck woke up, they ran to the hatch also to open it...but it was fully engulfed in flames. By the time the crew woke up, probably a lot of the people on the lower deck were dead or beyond rescuing. It must have been fast, because anybody who could have gotten to the hatch could have gotten out easily. (Unless the hatch really was locked, so that needs checking.)

It seems that it may have started in the galley and spread out on either side, because they had charging stations in the galley and probably somebody’s lithium battery exploded or overheated and set fire to something nearby. People charge their professional-level video cameras there, and some of these have bigger batteries.

Some boats only let people charge batteries at stations on the deck. Bet that’s going to be a law soon.

[Ol' Dan Tucker]

Thanks for the pic.

[LeonardFMason]

“Interesting that they’ve been unable to recover and identify just ONE person.”

SOMETHING is off with this whole thing.

Who is the one person(body) NOT found?

[Flaming Conservative]

Could you please dummy down the lithium charger info for the technically challenged among us?

[_Jim]

re: “ If it has the protection circuit board built into the pack, it can most likely be ruled out. “

No.

[DoodleDawg]

The NTSB is fairly competent at this sort of thing.

Then let's see what their investigation shows. I imagine they've barely gotten started and most of their evidence is in 150 feet of water.

[sheana]

It doesn’t matter what the 911 guy said. The stairs down to the bunks didn’t have a door. No way to lock it. The escape hatch was a piece of plywood that when you pushed up on it it just pushed out. No locks. There were no locks on the boat to lock! I’ve been on dive boats such as these. I know people who own/run them. The boats are wide open where passengers can wander at will.

[_Jim]

re: “ If it has the protection circuit board built into the pack, it can most likely be ruled out. “

No.

During testing of Li-Ion chargers and using used cells (from a laptop battery pack), I have had cells which never saw a terminal voltage over 4.1 Volts begin to “self heat” (as it began to self discharge due to an internal short that developed AFTER having seem a full charge).

Fortunately, I didn’t have any ‘flame on’ happen or ‘cell swelling’ (due to internal gas buildup) take place.

[yesthatjallen]

These diagrams highlight why these boats need to be redesigned.

The staircase and the escape hatch are located in the same general area.

There is essentially a bottleneck to one exit route and that one exit route lead to the fire.

[yesthatjallen]

Lithium batteries are prone to spontaneous combustion.

[McGavin999]

If I owned a boat no one with a battery would be allowed onboard without one of those bags. 33 people, all with cellphones and cameras...hindsight is always 20-20 and we don’t really know if this was the cause, but now we know it could be the cause.

[rivercat]

Stop posting BS that’s been disproved many times.

I’ve been on this boat several times. The doors to the galley were NOT LOCKED. There are fire extinguishers all over the place.

[Ol' Dan Tucker]

Could you please dummy down the lithium charger info for the technically challenged among us?

Sure thing.

A little lithium battery background. When a non-lithium battery is overcharged, it will usually just get hot. Ditto when it's over-discharged. When a lithium battery is overcharged or over-discharged, it develops internal shorts.

With enough of these shorts the battery will enter what's known as thermal run-away. IOW, the internals start to break-down producing heat, which starts to cook the lithium in the battery. This produces toxic white smoke that will turn the flat pack into a silver sausage. Eventually, the mylar outer skin will burst exposing the lithium to the air.

When this happens, the lithium catches fire.

Here's a pic of a LIPO (lithium polymer) battery pack. These are the type of lithium batteries used in most consumer electronics, such as phones, etc.

See the circuit board that's located where the red and black wires enter the pack? That's the protection circuit. It's constantly monitoring pack voltage to prevent overcharges or over-discharges.

Here's a LIPO that doesn't have the circuit.

Here's a pic of a normal hobby LIPO and one that's puffed, meaning it's developed internal shorts and should not be used.

[pbear8]

Who is the one person(body) NOT found?

They were in the water, the boat burned, the missing body may have floated off. The family knows who they are.

[Ol' Dan Tucker]

During testing of Li-Ion chargers and using used cells (from a laptop battery pack), I have had cells which never saw a terminal voltage over 4.1 Volts begin to “self heat” (as it began to self discharge due to an internal short that developed AFTER having seem a full charge).

During your testing were you monitoring individual cell voltages within the pack? IOW, were you testing individual cells or full packs?

Here's the rub.

LIPOs are also sensitive to over-discharge. If one of the cells in the pack is out of balance with the other cells, the voltage can drop below 3V. This can (not will) trigger internal shorts.

[treetopsandroofs]

I’m reminded that 34 others died in the Ron Brown take-down.

https://www.politico.com/story/2017/04/ron-brown-dies-in-plane-crash-april-3-1996-236759

[treetopsandroofs]

Yes, let’s assume the best, as this doesn’t seem to be DIRECTLY related to politics.

[doorgunner69]

Not a diver, are you?

[Drew68]

Smoking grass or mainlining, and fire started, accelerants in the vicinity caught fire.

Maybe a crew member was masturbating to internet porn and knocked over a kerosene lantern?

I mean, let's cover all the bases here.