Hundreds of passengers aboard three British Airways flights endured flights to nowhere on Saturday due to technical problems.
Two of the departures were long-haul flights on Boeing 777 jets; the third was a Mediterranean island service using an Airbus.
The problems began on BA263 from London Heathrow to Riyadh, the capital of Saudi Arabia.
According to Flightradar24, the Riyadh flight took off from Heathrow slightly late at 2.47pm British time. At 4.25pm, while flying over the Croatian coast, the aircraft turned around and flew back to its starting point, where it landed at 6.32pm.
The cause was believed to be an issue with the traffic collision avoidance system, which meant the aircraft was not compliant with Saudi airspace requirements.
Passengers were put up in Heathrow area hotels overnight. The replacement flight departed just before 11am on Sunday, making it 21 hours behind schedule.
Travellers booked to fly from Riyadh to Heathrow in the early hours of Sunday morning spent two unexpected nights in the Saudi capital: their flight is currently 30 hours behind schedule, with arrival expected around 1.30pm on Monday afternoon.
The second turn-back involved British Airways flight BA586 from Heathrow to Bastia on the French island of Corsica. The Airbus A320 was two-thirds of the way through its journey, flying over central Switzerland, when it turned around – landing three hours later back where the passengers had started.
The flight eventually operated the following day, arriving over 20 hours late.
The third flight to return to Heathrow was BA203 to Boston. Its passengers had the shortest “flight to nowhere”. The Boeing 777 took off at 5.17pm. It had been airborne for only 16 minutes and was at 13,000 feet over Gloucestershire when the jet turned back.
But congestion at Heathrow meant the journey back to Heathrow took twice as long as the westbound leg: the plane had to circle over Surrey before touching down.
The flight to the Massachusetts capital was cancelled rather than rescheduled, with outbound and inbound passengers rebooked on other services.
A British Airways spokesperson said: “We are extremely sorry for the delay to our customers’ journeys. We would never operate a flight unless it was safe to do so.”
The Independent estimates that at least 700 departing passengers, and the same number of arrivals, were affected. If they were all to successfully claim compensation for the delays, the cost to British Airways would be around £650,000 – on top of hundreds of thousands of pounds in costs for hotel accommodation, meals and aircraft fuel.
On Sunday a fourth British Airways departure from London made a swift return to base: the BA CityFlyer service from London City airport to Malaga turned back just seven minutes after take-off, landing nine minutes later.
Emergency vehicles met the aircraft on arrival.
A British Airways spokesperson said: “Due to a minor technical issue the aircraft returned to London City airport and landed safely. Our airport teams assisted customers and rebooked them onto alternate services.”