Heads up regarding Electrical Fire

I was off watch and asleep when an acrid smell woke me and then there was pandemonium. We were full of toxic smoke below and had no idea what was going on, so I grabbed a fire extinguisher from my cabin wall and tried to make sense of it. The owner had the companionway ladder hatch up and the smoke was pouring from the engine area but none of us had half a clue why. We were gagging and coughing and our eyes were stinging.

Obviously we used the cockpit toggle to shut down the engine but the smoke poured unabated.

What had happened was that the starter motor had suddenly jammed in gear, so it is doing 20 times the revs of the engine, which is more than a tad over spec on a continuous basis. What’s 20 x 2500? Typically, a solenoid disengages the starter motor once the engine has fired but this depends on a circuit leading from the ignition switch which had spat the dummy. It wasn’t anything to do with the down below stuff, until wire insulation melt-down caused a major short circuit. I mean you like a bit of charge, but this was Le Mans. Melt-down was an immediate consequence.

After the event, we know the key ignition system to be the cause, because when the fried starter motor was replaced the same thing happened (quickly shut down). When the ignition key mechanism was replaced, all was well.

A couple of lessons were learned.

• Key / ignition circuits tend to be partially exposed and are not failsafe.
• The toxic smoke is caused by wire insulation meltdown. There is (initially) no actual fire. At least in the early stages, discharge of a fire extinguisher is going to cause more problems than it solves (visibility, air, finding the seat of the problem). The wrong fire extinguisher will get you into even worse straits.
• Insulation meltdown will usually cause a short circuit which escalates the drama.
• Turning the battery isolation switch to all off should be an early response but depending on how the boat is wired, might do bugger all.
• Symptoms are a high pitched whining sound, emanating from the bearings in the starter motor, then smoke. Big heat in the starter motor, although you can’t identify that when you can’t see anything in the engine compartment anyway.
• There is a pretty good argument for having a CO2 fire suppression system in the engine compartment. But I am not sure that this would have come into play early enough in our circumstance. The drama was smoke rather than fire although fire would surely have eventuated.

Thoughts:

• If you hear unusual whining, and there is smoke, it could be engine bearings or other stuff but it might also be electrical gear. Probably is.
• Toggle off the engine and also switch off at the key (this is the crucial learning).
• Depending on the conditions, dump the main halyard and work on headsail on a 3/4. Just let the de-powered main do whatever it wants. If someone has time to drag it down safely and sheet it in, fine. You have worse problems happening.
• Stay calm. You will get a lot more done faster. The tone of your voice will have a lot to do with how efficiently your crewmates react.
• Presuming some electrics still work, do not hesitate a moment re radio broadcast. 15 seconds later it might be impossible. If there is smoke / fire, don’t Pan Pan Mayday on channel 16. Worry about whether you have over-reacted later.
• Know the mayday sequence re info. Name, position, nature of emergency, people on board, intentions etc. If you are not au fait, have it on a laminated card glued to the radio or bulkhead. Here I am presuming that you have GPS in the cockpit for lat and long. I think you must have this info on deck.
• Fire off a flare. If you don’t know how to do this safely then learn now. There are simple and inexpensive courses available.
• Ideally you will have a waterproof hand-held VHF charged, and on deck. Again, don’t hesitate for a moment. Mayday. When it comes to life threatening situations, handheld VHF starts to look incredibly cheap.
• Count. You know how many people are on board. Know where they are. Get them on deck doing anything that’s useful in terms of flotation eg as simple as gathering fenders. Give them something (safe) to do. Be in control and normal.
• Depending on circumstances and level of panic, grab a fender, bowline it to whatever line is handy and dump it overboard aft. It will be up to the individual whether they want to go overboard and hang on.
• Find the fire extinguisher/s. Have someone near (but clear) with it but do not position them where a fire might prevent exit or smoke might cause unconsciousness.
• Don’t use the extinguisher until there are actual flames.
• There is a good argument for having an extra extinguisher in a cockpit locker where it is accessible in the open air. You don’t have to brave an inferno or choking smoke to get your hands on an extinguisher.
• If possible, delegate someone to hold their breath and throw up the grab bag, epirb, hand-held VHF, lifejackets, flares, hand held GPS, water bottles etc provided that a fire will not trap them. I am probably going to cop flack over this but if you’re abandoning a ship on fire, there is much that you might find useful and risk is part of the equation. There are times when you must gamble. Or you could take up stamp collecting.
• If there is time, disconnect and throw the LPG bottle overboard, plus fuel containers.
• Realise that the main enemy is toxic smoke rather than fire.
• There is a lot to be said for trying to control the situation and more to be said for being able to get out of it alive.
• If smoke levels make it possible, turn batteries to all off, and better still, rip out a primary battery cable with all your strength. Try to find something cloth-wise to put over your hand or you might be badly burned.
• All off should in theory break all circuits, but that depends on whether anything has been hot-wired over the years, and things usually have been. If there is time, turn everything off at the switchboard, but there probably wont be time.
• Do not, on the face of it, open hatches to clear smoke as breeze will encourage fire and limit the time you have to consider and execute escape options. It is better to be unsafe in the water than unsafe on a burning boat.
• Depending on where you are, your burning boat makes a decent flare. Where we were, there was no one to see it.
• Keep at lest some flotation gear above deck eg lazarette, rather than under the V-berth forward.

Problem is that all this stuff needs to be done pretty much simultaneously. Pre-plan. Have a clear idea in your head about what to do, numbers aboard, immediate tasks and delegation and above all, preservation of life. Write it down and laminate it and stick it in the front of your diary. An occasional five seconds of reference to this will imprint it in your mind and save a great deal of time and when it comes to fire, time is the enemy.

Fire is every sailors nightmare and your electrics threaten it more than you might think. All this happened to us and was contained within two minutes that seemed like two hours. I emerged from the situation vomiting and with burned hands from ripping out the battery cables. The boat was saved but I don’t want to do it again.

Sometimes I think we take our safety at sea too much for granted in the electrics sense. I have survived some spectacular weather but in over 40 years out there no one has told me about the potential hazards associated with the starter key mechanism. How about that?

People far more technically adept than me will know how to prevent and deal with this issue and I invite comment. Thing is though that drama happens and fire is up there with the worst and has to be thought about and actions pre-planned.