Investigations by Irish authorities have discovered no evidence of depressurisation or toxic contamination, two years after a mysterious Germanwings Airbus A319 incident that resulted in the crew's issuing a Mayday call.
The aircraft, registration D-AGWK, was operating on a scheduled flight from Dublin to Cologne on 27 May 2008 when its crew members reported feeling unwell shortly after take-off. The flight's purser also reported to the flight crew that "almost all the passengers had fallen asleep", says the report from Ireland's Air Accident Investigation Unit (AAIU).
Six crew members and 119 passengers were on board the aircraft which, according to Flightglobal's ACAS database, was barely a month old at the time.
The captain reported feeling unwell and he later recalled feeling a "tingling sensation in his right arm, comparable with the arm 'falling asleep'", says the AAIU. "At this point, the aircraft was now approaching [flight level] 200. The cockpit crew's initial concern was a possible pressurisation problem."
However, the cockpit displays did not show any warnings or failures, says the report. "A decision was made to don oxygen masks, declare an emergency and descend," it adds. After the flight crew donned oxygen masks, their symptoms disappeared.
The aircraft issued a Mayday call and subsequently landed without incident at Dublin Airport. Investigations after the incident were inconclusive, with no evidence of loss of pressurisation in the aircraft, or contamination of the aircraft's air supply.
Meteorological factors and crew fatigue were also ruled out as contributors to the incident. "The probable cause of the adverse symptoms reported by the aircraft crew and some passengers could not be determined," says the report.
The AAIU, however, recommends that the Irish Aviation Authority should ensure the provision of adequate medical services at large airports. There was no on-site doctor at Dublin Airport after the incident, and "such a presence would have been useful to the investigation", says the report.
It also recommends that Dublin Airport Authority reviews its procedures in response to such events and ensure that passengers and crews are not detained in "a potentially toxic environment, following cabin air quality events". The aircraft's passengers and crew had been held in the aircraft for an hour after it landed before they were given the go-ahead to disembark.