Propane disaster

[Editor’s note: The following is a first-hand account of a propane explosion on the 55-foot Nicholson yawl, Lord Trenchard, owned by the British Armed Forces and used for adventure training for military personnel. The yacht was alongside the town dock in Poole, on the south coast of England, when the blast occurred. Two people were injured, one very seriously. This story, with all its gory detail, should be a cautionary tale for anyone with a propane system aboard their yacht.]

"The sound of people moving around the cabin and quiet conversation wakes me. It is broad daylight, and I glance at my watch. Six fifty-five — I can doze in the quarter berth for a few more minutes. I pull the bunk curtain aside just in time to see two of the crew disappear up the companionway with their shower gear. The skipper, Colin Rouse, is up and about. ‘What’s the weather like?’ I ask. ‘Fine,’ he answers. ‘Looks good for the passage. Kettle’s on.’

"I lie back and think about the plan for the day. Seven new crewmembers will be joining us after breakfast, and in my mind I run through the briefing that they will need before we can set off. Our plan is to sail across the English Channel to Cherbourg in France, about 130 miles. I hear the generator, fitted below the cockpit, turn over as Colin tries to start it from the control panel by the saloon steps. It doesn’t start the first time, and then I hear it turn over again.

"Chaos. I am conscious of the most excruciating pain; the whole of my right leg feels as though it is being electrocuted. The agony goes on and on and on. I can’t see. I’m covered in something white and translucent. There is no noise, and then I hear screaming, deep cries of agony; it takes a finite time for me to realize that the screaming is coming from me. Illogically, I think that something must have happened to the generator and live cables have dropped across my leg. After what seems like an age, the pain starts to ease. Faintly, I hear a voice. ‘He’s lost his leg.’ I turn my head to the right and see a severed leg lying beside my bunk where the chart table seat should be. For one dreadful, heart-stopping moment I think that it is mine. Then I realize that the leg is deeply tanned and wearing a shoe and sock — it can’t be me.

"I lose consciousness at this point and the next thing I am aware of is someone dragging me from the remnants of the quarter berth. They are pulling shattered sheets of fiberglass off me. I am lying on the bare hull; the bunk has disappeared from under me. My rescuers drag me through the gaping hole where the coach roof had been. There is a stink of fiberglass, as though I was in a boatbuilding shop. My face and eyes are covered in blood and something seems to have happened to my right foot — it’s bleeding and won’t take my weight. I look back into the wreckage of what had been the saloon. Colin is lying there with people working on him. The stump of his leg is pointing straight toward me. The cabin is devastated — I cannot conceive what has happened. There is blood everywhere.

"I recall nothing else until I step onto the jetty from the square-rigged training ship Royalist, alongside which Lord Trenchard is berthed. There are police cars and ambulances all over the quay and more are arriving. I only hear their sirens faintly. There is a lot of broken glass and a crowd is beginning to form, held back by the police. A sergeant is talking to me, but I can’t really absorb what he is saying. He shakes my shoulders. ‘How many people were onboard. How many?’ I try to pull myself together. ‘Four,’ I answer.

"I look back at Lord Trenchard. The whole of the cockpit and afterdeck has disappeared, leaving a gaping hole some 20 feet long. The mizzenmast has fallen forward and the aft end of the coach roof has been torn off. I can see a deep split running down the hull from the coaming to the waterline. The whole deck has been lifted and all the windows blown out. Only at this moment does my mind register what has happened — explosion. I want to go back to the boat to help Colin, but sensibly, I’m not allowed to. ‘He’s all right — he’s being looked after,’ I am told. Still dripping blood, I am put into an ambulance and driven away."

That is the reality of a propane explosion. The violence of the event is beyond belief. The blast was heard over four miles away and windows blown out on the quay, despite being shielded by the bulk of Royalist inboard of Lord Trenchard. The other two crewmembers onboard, who had, like me, been lying in their bunks, were miraculously uninjured, but very shocked. The two crewmen who had just stepped onto the jetty probably saved Colin’s life. They recall looking around to see parts of the boat — including the complete wheel and binnacle — flying high in the air. They came back onboard and administered first aid, helped by officers from Royalist, until medical help arrived.

The emergency services deserve every praise. A Poole lifeboat came alongside and together with Royalist supported Lord Trenchard to keep her afloat; she was making a lot of water from the splits in the hull and damaged seawater systems. After Colin got ashore, she was towed to the other side of the harbor to be lifted out. I spent some time in casualty, together with members of Royalist’s crew who had suffered cuts and bruises. I had the gashes in my foot stitched up — the cuts to my face were only superficial — and discovered that both my eardrums had burst. The initial pain in my leg, which had been only a few inches from the seat of the blast, was explained to me; the shock of the explosion had stimulated all the nerves in it at once, a common blast effect.

Whilst being treated I heard that Colin’s left leg had been amputated above the knee. His other leg was badly damaged but had mercifully been saved. He also had injuries to his hand and neck, and although critically ill, was out of immediate danger.

Later that day I went back down to Lord Trenchard to try to retrieve some of my personal kit. She was still being kept afloat, but was half-full of water and diesel fuel. The interior was almost unrecognizable with virtually nothing left intact. The explosion had obviously happened under the cockpit and the blast had torn forward through the boat, ripping out the joinery, bulkheads and cabin sole. The forehatch, which had been secured with a massive wooden strongback, had been torn off. The chart table had been blown forward through the saloon, together with the radar and all the instruments. It seemed impossible that four people could have survived. Mixed in with the shattered fragments of fiberglass and plywood were the pathetic remains of personal possessions — shredded clothing and sleeping bags, books, toilet gear, Colin’s battered flute. It was a very shocking sight, made worse by the evidence of Colin’s injuries — splashes of blood and blood-soaked clothing.

How could such an accident happen? The Joint Services Adventurous Sail Training Center in Gosport has been running a fleet of 24 boats, including nine Nicholson 55s, for nearly 30 years. These boats are deployed worldwide — three of them were racing across the Indian Ocean when this accident happened. They have a regular program of refits and maintenance, and because many of the military personnel who sail in them are novices, safety procedures and routines are paramount. The British Marine Accident Investigation Branch carried out a very thorough inquiry into the explosion.

Like the other military Nicholson 55s, Lord Trenchard’s propane system consisted of two 9-lb cylinders, mounted in a locker sunk into the deck abreast the cockpit. Both cylinders were connected by flexible hoses to the regulator via a wall block, and from there a single, continuous copper gas-pipe ran to an isolating valve by the stove. A retaining plate secured the cylinders in the locker with just their shut-off valves exposed. One cylinder was turned on, whilst the other, shut off, was a stand-by, available when the in-use cylinder ran out. Whenever the cooker was not in use, the isolating valve beside it was kept shut. A gas alarm was fitted with two sensors, one beneath the cooker and one below the cockpit.

The evening before the accident, the in-use propane bottle ran out whilst supper was being cooked. It was turned off, the stand-by cylinder was turned on and a note made to change the empty cylinder the next day.

The accident report identified three failures that caused the explosion. First, the stand-by cylinder, which had been turned on the previous evening, had not been properly connected to its flexible pipe. The cylinder was recovered after the event, and the connection was loose. It had been attached during a previous trip made by Lord Trenchard a fortnight earlier and had been the stand-by cylinder since then. Thus, when, 12 hours before the explosion, this cylinder was turned on, propane at high-pressure leaked undetected directly from the bottle into the locker.

This propane should have drained overboard. However, examination of the locker, which was also recovered, revealed that it was not completely gas-tight. So an unknown proportion of the escaping propane leaked into the watertight compartment below the cockpit.

The final cause of the disaster was that the gas alarm failed to operate. The reason for this could not be determined — the alarm system was so badly damaged in the explosion that testing it was impossible. The report concluded that the generator starter motor supplied the spark that ignited the propane.

So three failures, one human and two material, caused this catastrophe. The most obvious lesson is that propane cylinders should always be turned off at the cylinder when the stove is not being used. But in many boats, this is inconvenient — the stowage locker is outside in the cold and wet, and it is often difficult to get at. It is worth noting that a solenoid shut-off valve, often fitted to overcome this inconvenience, would not have prevented this accident, as it would have been downstream of the loose connection.

But there are other lessons, too. Propane on boats is inherently dangerous, and to keep it safe we have to actively do things. We must turn the bottle on and off every time the stove is used and test our gas alarm systems by 9njecting propane into the sensors at regular intervals. We must periodically check that ourpropane lockers are indeed gas-tight and that the drains from them are not blocked. We must checknpipework and replace flexible hoses, test flame failure devices. Human nature is such that not all of these things will unfailingly get done.

ýWe should all consider whether we really do need propane on our boats. Nowadays, there are more alternatives available than the traditional kerosene stove. There are user-friendly diesel stoves on the market. Larger yachts with modern, quiet inboard generators might use electricity for their cooking.

On a happier note, Colin made the most remarkable recovery, due largely to his amazing cheerfulness and fortitude together with the unstinting support of his partner Janis. Within a week he was terrorizing the nurses in hospital and within a fortnight he was home. Although the adjustment has not been easy, he gets around well on a marvelous artificial leg. He no longer works as a Nicholson skipper but has not given up sailing. Last summer he campaigned a yacht in the grueling Fastnet race under the auspices of BLESMA, the British Limbless Ex-Servicemen’s Association. All the crew have lost one or both legs. It was a successful venture, and they had a lot of fun.

Accidents happen, but ones involving propane are more horrible than most. We were fortunate that no one was killed on Lord Trenchard. Had the explosion happened the previous day, with the yacht at sea and everyone onboard in the cockpit, or had we all been sitting around the saloon table, undoubtedly lives would have been lost, quite possibly the whole crew. To prevent such a disaster happening to you, if you must have propane on your yacht, always, always turn it off at the bottle.

A former Royal Navy officer, Gavin McLaren worked for the Ministry of Defence as a Nicholson 55 skipper from 1988 until 1992, when he and his wife Georgie spent four years extended cruising in their Rival 41, Margaret Wroughton, visiting the Caribbean and the U.S. East Coast.

He was re-employed as a Nicholson skipper in 1999, just two weeks before the accident described here, and was sailing aboard Lord Trenchard as the mate, refamiliarizing himself with the boat. He is the author of North Biscay Pilot and the forthcoming new edition of the Atlantic Crossing Guide.

By Ocean Navigator