Gatwick Airport had fire crews on standby
A plane bound for Barbados was forced to return to Gatwick Airport after the captain reported a technical problem.
The Virgin Atlantic flight returned to the West Sussex airport an hour after take-off but the airline said it was simply a precautionary measure.
Gatwick Airport said the Boeing 747-400 had declared a problem and the fire service had been put on standby.
Virgin said the 320 passengers were put on a replacement flight to Barbados on Saturday at 2115 BST.
A Virgin spokesman said an investigation into why flight VS29 returned to Gatwick was under way.
"The captain of the aircraft decided as a precautionary measure to go back to Gatwick," he said.
"Virgin Atlantic gives the highest priority to the safety and security of its passengers and crew. Virgin Atlantic apologises for the inconvenience caused and the delay to passengers' journeys."
The plane landed back in Gatwick about 1100 BST.
Delayed passengers and 15 crew members were given vouchers while waiting for their second flight, which left 11 hours after the original scheduled departure time.
Virgin Atlantic said it would offer passengers a partial refund as they were delayed longer than five hours.
A spokeswoman for the Air Accidents Investigation Branch (AAIB) said it had been notified but were not investigating the incident.