The UK’s Civil Aviation Authority confirmed that both pilots were alone on the flight deck at the time of the incidents, meaning there was noone flying the plane.

On the first occasion the captain allegedly left the flight deck to use the toilet. When he tried to radio the first officer, there was no reply and he returned to find his second in charge fast asleep at the controls, according to

In the second case, a pilot returning from his break had to shake his co-pilot awake.

Pilots have raised concerns that new flying hours imposed by the EU could lead to pilots being exhausted. Under the new rules, pilots could be in a position where they’re landing commercial jets after having been awake for up to 22 hours awake.

UK pilots currently go up to 18 hours without sleep, with at least four in ten report nodding off on a flight. A third of those pilots who did fall asleep report waking up to find their co-pilot also sleeping.

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