A call to limit long working hours in the aviation sector has been made after investigators highlighted fatigue as a contributor to engine problems which prompted an emergency landing at Heathrow.
The British Airways Airbus A319 bound for Oslo with 75 passengers and five crew had to return to the airport four minutes into its flight with one engine damaged and another on fire.
The Air Accident Investigation Branch (AAIB) pointed to a maintenance error which had led to fan cowl doors being left unlatched on both engines. Both detached from the aircraft, damaging the Airbus and a number of its systems.
Leaking fuel from a damaged fuel pipe on the right engine ignited and an external fire developed, meaning that the aircraft had to be flown back on a single engine.
“A number of passengers saw fuel leaking from the right engine. One passenger highlighted the leaking fluid to a member of the cabin crew, stating that it appeared to be fuel, but was told that it was not. Photographs taken by passengers show a significant fluid leak from the right engine,” according to the AAIB report.
The aircraft was met by fire crews having landed safely and passengers were evacuated using emergency escape slides.
“A number of organisational factors were contributory to the maintenance error. The operator has since taken action to address these issues,” the AAIB said while making five safety recommendations in the wake of the incident which occurred in May 2013.
Both technicians working on the aircraft the previous night were on overtime and it was not their regular shift.
The AAIB found that “there were no other means of assessing the level of fatigue in maintenance workers, based on their actual attendance record including any overtime worked”.
The report said: “Both technicians were working in compliance with the company’s working time policy. However, analysis of their working time records showed that there was an increased risk that their performance could be compromised by fatigue.
“This was induced by the significant level of planned and overtime working that they had carried out prior to and including the shift in question.”
Responding to the report, Dr Rob Hunter, head of flight safety at the British Airline Pilots’ Association (Balpa), said: “Balpa has been highlighting the prevalence of fatigue amongst pilots in recent years.
“The AAIB’s report makes it clear that the problem goes beyond pilots and could well be affecting other workers in safety-critical roles in aviation.”
“We hope EASA [the European Aviation Safety Agency] takes full notice of the fatigue elements in this report and implements the AAIB’s safety recommendations. EASA should also bear in mind our continual warning that fatigue is an insidious problem in aviation which must be taken seriously.”
BA executive chairman, Keith Williams, said: “The safety of our customers and crew is always our highest priority.
“The changes we have already made to our procedures, along with the safety recommendations for EASA and Airbus, will prevent occurrences of this type of incident in the future.”
Although the hours of technicians were compliant with working time legislation, the company had restructured its overnight engineering teams, BA added.