A Virgin Atlantic flight was forced to turn around after it emerged that one of the pilots had not completed all of their company training.
Flight VS3, which was en route to New York after taking off from Heathrow on Monday, was ordered to return around half an hour after taking off.
The Airbus A330 arrived back at the London-based airport about an hour later, where the co-pilot was replaced.
Despite the first officer being fully licensed and qualified to operate the aircraft, they had not completed the “final assessment flight” required by the airline.
As a result, the captain had not been given designated trainer status and the pairing of pilots was in breach of “internal training protocols” but not of UK aviation and safety regulations.
A Civil Aviation Authority spokesperson said it was made aware of the incident by the airline and confirmed “both pilots were suitably licensed and qualified to undertake the flight”.
The captain has been described as “highly experienced” with “many thousands of hours of flight time during 17 years at Virgin Atlantic”, while his co-pilot was said to have joined the airline in 2017.
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Virgin Atlantic, which is largely owned by billionaire Richard Branson, blamed the incident on a “rostering error” and said the officer was replaced to ensure “full compliance” with its protocols.
After the change was made, the flight was able to resume and eventually landed at New York’s JFK airport around two hours and 40 minutes later than planned.
Meanwhile, internal operations at Virgin Atlantic have been reviewed and updated to avoid a similar incident from happening in the future.
The airline apologised for the inconvenience caused to its customers.