Half pilots 'have slept in flight'
More than half of pilots have fallen asleep on the flight deck, according to a survey by pilots' union Balpa.
And of the 56% who admitted nodding off, as many as 29% said they awoke to find the other pilot asleep.
Balpa said the survey results enforced its argument that proposed European changes to flight-time regulations could endanger flight safety.
House of Commons Transport Committee chairman Louise Ellman is also concerned about the European proposals.
But the Civil Aviation Authority (CAA) has said the changes, due to be voted on next week, will "maintain the UK's current high safety standards".
Of the 500 commercial pilots polled for today's survey, 43% said they believed their abilities had been compromised at least once a month in the last six months by tiredness, with 84% saying it has been compromised at some stage during the past six months.
Also, 31% did not believe their airline had a culture that lent itself to reporting tiredness concerns, with only half (51%) saying they believed their airline chief executive would back them if they refused to fly because of tiredness.
Unprompted, 49% said pilot tiredness was the biggest threat to flight safety - three times more than any other threat.
Balpa general secretary Jim McAuslan said: 'Making every flight a safe flight is the number one priority for British pilots who have helped establish some of the highest safety standards in Europe.
"Tiredness is already a major challenge for pilots who are deeply concerned that unscientific new EU rules will cut UK standards and lead to increased levels of tiredness, which has been shown to be a major contributory factor in air accidents."
Mrs Ellman said: "I agree with Balpa's concerns that the proposed changes to EU rules could endanger air passenger safety.
"Our committee has already warned that the changes could mean pilots landing planes after being awake for 22 hours."
She went on: "We have called for scientific evidence to be used to judge just how long pilots should be awake. There is still time for the UK Government and Europe to think again."
A CAA spokeswoman said: "Aviation safety is our number one priority. We think the new European flight-time limitation regulations maintain the UK's current high safety levels, and will actually increase safety for UK passengers travelling on some other European airlines.
"This view is informed by expert opinion based on scientific principles, operational knowledge, regulatory oversight information and research."
He went on: "The changes will give the CAA far greater access to airline data to help us oversee fatigue risk management. We will shortly begin working with UK airlines over the introduction of the new system.
"Once implemented, we will take responsibility for enforcing the regulations, and promoting a robust reporting culture. We will also work closely with the EC and the European Aviation Safety Agency over air crew fatigue management issues."
Meanwhile, the CAA said today that, in an incident widely reported yesterday, both pilots did not fall asleep at the same time while flying a UK-operated Airbus passenger plane.
The CAA had released a report, following a request under the Freedom of Information Act, which suggested that both pilots nodded off after they had only five hours of sleep in the previous two nights.
The airline, which has not been named, had submitted the report to the CAA.
The CAA said today: " Following clarification from the airline concerned, the CAA is satisfied that while this was a reportable event, and both pilots were concerned they were suffering symptoms of severe fatigue and took controlled rest separately, they did not fall asleep at the same time.
"It was right that the airline reported this to us after one of the pilots raised their concerns. The airline is now taking steps to adjust its rostering arrangements for flight crew."
The CAA went on: "The safety reporting procedures are designed to help us enhance aviation safety and ensure we base our actions on the best information available.
"Aviation safety is our number one priority and we will take all necessary action to ensure that reportable events are carefully considered and where problems are identified, lessons are learned."