Mysterious toilet blockages plague Cathay flights

(AFP/JOHN MACDOUGALL)

Cathay Pacific said Wednesday it has endured a spate of mysterious toilet blockages on its Airbus fleet, with one packed plane forced to make an unscheduled landing because it had no working lavatory.

Toilets on the Hong Kong airline's Airbus A330 and A340 planes have been blocked in three separate incidents over the past 11 days, Cathay spokeswoman Carolyn Leung told AFP, confirming a report by the South China Morning Post.

One November 17 flight from Riyadh in Saudi Arabia to Hong Kong carrying 278 passengers was forced to divert to Mumbai, when flight attendants discovered shortly after take-off that none of the plane's 10 toilets was working.

The enforced detour caused an 18-hour delay on what should have been an eight-hour flight.

The two other flights affected by blocked toilets were from Rome to Hong Kong on November 9 and Dubai to Hong Kong on November 19.

In both cases, the number of passengers had to be restricted to fewer than 240 when it was discovered before take-off that only toilets on one side of the plane were functioning.

The exact cause of the toilet blockages remained unclear, the spokeswoman said, adding that passengers might be partly to blame.

"You would be amazed at what we find in the pipes when we clean the system - not just face towels but medicine bottles, socks, items of clothing and even children's stuffed toys," Leung said.

The airline said it has consulted Airbus about the problem and its engineers are now fitting new pipes and carrying out deep-cleaning treatment on toilets.

Aircraft toilets use high-speed pipes that carry waste at up to 110 kilometres (68 miles) an hour into a holding tank which is emptied between flights.

Two vacuum systems operate separately on each side of the plane, meaning that a blockage usually affects all toilets on one side of the aircraft.

Cathay's internal guidelines say the minimum toilet-to-passenger ratio in economy class should be one to 80.