UK pilots' organisation Balpa said last month's incident "comes as no surprise", adding that it had "repeatedly warned the CAA of the risk of both pilots falling asleep, including in a letter to each member of the CAA board last year".
Balpa general secretary Jim McAuslan said: "British pilots want to make every flight a safe flight and tiredness is the biggest challenge they face.
"As the regulator responsible for UK flight safety, the CAA has been far too complacent about the levels of tiredness among British pilots and failing to acknowledge the scale of the under-reported problem.
"In fact, the CAA and Government are backing EU cuts to UK flight safety that will increase tiredness among pilots and the risk of dangerous incidents."
The CAA said today: "We understand that Balpa are not happy with the proposals but we think overall it is a good package and not much different to what we have now."
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