Jet with hundreds of passengers aboard plummets 30,000ft in emergency descent

Charter flight from Stansted to Poland's Rzeszow Airport carrying 262 passengers diverted to Amsterdam Schiphol in March last year after alarms activated

(Getty Images)

A passenger jet en route from London to Poland with more than 260 passengers aboard was forced to make an “emergency descent” from 37,000 feet after the cabin failed to pressurise properly, a report has found.

The Titan Air Boeing 767 charter flight from Stansted to Rzeszow Airport, in south east Poland, had just started cruising at high altitude when alarms started going off, an Air Accidents Investigation Branch (AAIB) report found.

The passenger oxygen masks came down and the pilot brought the twin-engine plane down by 30,000 feet and diverted to land at Amsterdam's Schiphol Airport after issuing a mayday call on 19 March last year.

The AAIB investigation found that a faulty positive pressure relief valve (PPRV) meant the aircraft had not pressurised correctly after taking off from the Essex air hub.

Both the aircraft's PPRVs had been replaced with “overhauled” values during “heavy maintenance” before the flight, the report said.

But it added a prior test flight had shown no problems and examination of the part after the incident discovered “no obvious reason for the malfunction”.

Data from the flight recorder showed the seatbelt signs automatically illuminated at 9.40am, some 20 minutes after take-off from Stansted.

The aircraft has 262 passengers and nine crew aboard at the time.

The report concluded: “The failure of the cabin to pressurise correctly resulted from a faulty PPRV which was installed during recent maintenance.

“The maintenance checks of the replacement valves did not identify the defect with the fault PPRV.

“The event was a failure to pressurise correctly, rather than a sudden depressurisation and the crew's timely actions in identifying the problem and carrying out the appropriate emergency procedures ensured a safe outcome.”

PA