NINJA II: The Fuel Cap He Opened to Check a Stalled Engine Nearly Killed Him

Utah Beach, 12 June 2013 — 04:00

NINJA II, a 7.99m aluminium potting and netting boat working out of Utah Beach in Normandy, had been fishing for whelks since 02:30. Two aboard: the skipper, 36, and a 20-year-old deckhand. Both properly qualified, both medically fit, neither reporting fatigue. Nothing about the morning suggested anything was wrong — until the auxiliary petrol-hydraulic motor that drove the pot-hauler winch simply stopped.

What Happened

The motor had been replaced at the start of the month and had needed a few dealer call-outs since — but had run perfectly for the five days before the accident. When it stalled just before the fourth string of pots, the skipper's first assumption was the obvious one: low on fuel. The motor sat in the wheelhouse, on the port side. He opened the fuel tank cap to check the level.

A violent explosion followed. The motor caught fire. The skipper suffered severe burns to his arms and face. With the wheelhouse now inaccessible, neither raising the alarm nor reaching the fire extinguisher was possible from inside it — the crew fought the fire with buckets of seawater instead, and got it under control. The electrical panel and every navigation and communication instrument were damaged by the heat. They beached the boat, hauled it out on its usual tractor and trailer, and drove the skipper to hospital themselves — 40km to Coutances. The owner only learned what had happened from a note left on board.

What the Investigation Found

BEAmer's investigation couldn't establish with certainty exactly what ignited the vapour, but the physical picture was clear enough. The most likely explanation: the engine had stalled from flooding, caused by a sticking needle valve letting too much fuel through to the carburettor (the tank feeds it under gravity pressure). A year on, investigators were still examining whether a badly-routed breather hose during the engine's installation had caused crankcase overpressure — and found the oil level in the crankcase unusually high, mixed with a significant quantity of petrol. What's certain is where it happened: petrol vapour (flash point 40°C) ignited in a confined space the moment the tank cap came off.

The Consequences

Third-degree burns to both arms and his face put the skipper in the burns unit at Nantes for five days, including a skin graft to his left arm. His original three-month medical leave was extended by another three months. The owner replaced the motor-hydraulic unit — reinstalled in the same spot — and added a second fire extinguisher outside the wheelhouse. On 11 July 2013, Cherbourg's vessel safety centre formally required the unit to be relocated outside the wheelhouse entirely, and a second extinguisher stored there permanently.

The Real Lesson

A petrol-fuelled engine, in a confined space, with no preventive measures in place — that combination is what BEAmer's own finding names as the direct contributor, not a single freak failure. The instinct to open a fuel cap and look was completely ordinary; it's exactly what happens next to that engine, and where that engine is installed, that decided the outcome.

Check Your Vessel

• Skippers and deckhands: Is any petrol-fuelled auxiliary engine on your vessel installed inside an enclosed space — a wheelhouse, a below-deck compartment — rather than in the open air?
• All crew: Do you know where every fire extinguisher aboard actually is, and is at least one reachable from outside any space that could become inaccessible in a fire?
• Skipper/owner: If an engine that runs on petrol has recently needed repeat dealer attention, has the installation itself — not just the fault — been checked by someone independent?

Source: BEAmer (Bureau d'Enquêtes sur les Événements de Mer, France) — Rapport d'enquête simplifié, Incendie à bord du caseyeur-fileyeur NINJA II, 12 June 2013, published June 2014.