QE2’s engineers devise clever solution for stopping dangerous leak

The luxury cruise ship Queen Elizabeth 2 avoided going adrift in the Atlantic Ocean thanks to an ingenious solution devised by the crew to stop a leak in an engine room during a cruise last year, an investigation of the incident has concluded.

A leaking inlet pipe threatened to leave QE2 adrift.
   Image Credit: Cunard Line

The 70,327-grt QE2, perhaps the most famous cruise ship in service, was bound from Southampton, England, to New York in May 2002, when an engineer discovered a large leak in the aft engine room. At the time, the 963-foot vessel was carrying 1,457 passengers and 973 crewmembers, and was roughly halfway through its six-day voyage.

After failed attempts to stop the leak with clamps, rubber seals and other usual means, engineers devised an inflatable bladder, or bag, using spare parts from the ship’s watertight doors. They inserted the bag into the leaking pipe and filled it with air, thus stemming the inflow of water and allowing the ship to complete its voyage to New York, where it arrived two days later.

Had the crew not improvised a way to stem the flow of water, the leaking pipe could have failed completely, according to an investigative report issued in March by the Marine Accident Investigation Branch of the British Department for Transport. If that had happened, the vessel could easily have lost use of its propulsion motors in rough seas and swells, the report says.

Image Credit: Marine Accident Investigation Branch

Leak site created by corrosion along the pipe flange. The 11-square-inch hole allowed seawater to flow into the aft engine room at a rate of more than 39,000 gallons per hour.

“In this state, the vessel would have been disabled and drifted in poor weather conditions with a major compartment flooded,” the report said. “Even in this condition, it would have retained sufficient freeboard and stability to remain a safe haven for those onboard, but it was clearly a state that was undesirable and one having the potential for generating unforeseen risks.

“Steps taken by the engineering staff ensured that the situation did not deteriorate to this extreme.”

QE2, owned by Cunard Line Ltd., has made more than 500 trans-Atlantic crossings since its maiden voyage in 1969. The liner’s Southampton-New York sailings, however, will be taken over in April 2004 by Cunard’s new flagship, the 150,000-ton Queen Mary 2, which is still under construction in a French shipyard. QE2 will continue to make shorter Southampton-based cruises.

The drama unfolded at 0200 on May 21, 2002, when the senior watchkeeping engineer found a leak in the aft engine room during a routine inspection. The leak, coming through a puncture later measured at about 11 square inches, was caused by simple corrosion of the aging inlet pipe, which served an evaporator used to produce fresh water. The flow rate was later estimated at more than 39,000 gallons per hour.

Because the leak was located between the isolating valve and the vessel’s shell, it couldn’t be stopped simply by closing the valve. A crew of engineers at first attempted to solve the problem by clamping a rubber seal over the leaking pipe. At the same time, the water that had accumulated in the engine room was pumped into the oil-water holding tanks.

Soon thereafter, the high waters caused the aft engine room high-water alarm to sound and the port engine to shut down automatically. The crew shut down another engine manually, leaving no main engine running in the aft engine room.

As the water continued pouring into the engine room, it was pumped overboard as the crew tried to stop the leak using rope, canvas, clamps and various blocking media, such as silicone and sawdust, the report says. Nothing seemed to work, and hour after hour passed with no solution in sight.

Image Credit: Marine Accident Investigation Branch

Engineers devised the “top hat,” which was bolted to the leaking pipe.

In the meantime, some crewmembers were fabricating a device in a last-ditch effort to stop the leak. The device included a piece of steel in the shape of a top hat, which was bolted to the flange of the butterfly valve on the leaking pipe. A tube with a flexible bladder attached to the end was then inserted through the top of the contraption into the leaking pipe.

At 2100, or 19 hours after the leak was discovered, the problem was remedied. That’s when the crew inflated the bladder that had been inserted into the leaking pipe, using air from the ship’s compressed-air system. The inflated bag filled the faulty pipe and stopped the leak.

The report called the idea to use the bladder “particularly ingenious.” That’s because it wasn’t part of the ship’s damage-control equipment, but rather a spare part from the hydraulic system of the ship’s watertight doors.

“To recognize that these parts could be of use in this situation and, to an even greater degree, devise a method for their insertion into the failed pipe was very ingenious,” the report said. “Most marine engineers would hope to match this ingenuity under similar circumstances; it is probable that few would succeed.”

An air bladder was then inserted through the top hat and inflated to stem the leak.

In fact, had the device not worked, the faulty pipe could have failed altogether, thus allowing water to pour in at the rate of 264,000 gallons a minute, according to the report. It is questionable if the vessel’s bilge systems could have handled such a flow, the report added.

The crisis, however, wasn’t over yet. At 0915 the following day, the inflatable bag ended up failing and deflating, and water again flooded the aft engine room. But the engineers were ready and had the leak stopped an hour later, this time by repeating the first technique, except with a longer inflatable bag to ensure it wouldn’t deflate again.

The leak was kept under control until QE2 arrived in New York the morning of May 24. There, the leak and faulty pipe were repaired.

By Professional Mariner Staff