British holiday airline TUI has taken the definition of “no frills” to a new level after a family boarded one of its planes and discovered their seats were missing. The airline is now under scrutiny by authorities after the British family spent part of the flight sitting on the floor. The Taylor family were flying with TUI to Birmingham from a holiday in Menorca in June and boarded a plane to discover an empty space where their seats — 41D, E and F —  should have been. “We all just looked at each other as if to say 'where's our seats gone?'," Paula  Taylor told the BBC. The one remaining seat on the plane was given to the Taylors’ 10-year-old daughter, Brooke, while the adults were shown to flip up seats in the crew section. The Taylors said the after take-off the crew was busy serving food and other items stored behind the flip down seats. This meant they then had to go and sit on the floor in the space where their seats should have been. They were joined by Brooke because she did not want to sit alone. Airlines prevent people from sitting or sleeping on the floor because of the risk of injury if an aircraft hits unexpected turbulence.  Many make an announcement to this effect during the safety briefing. READ Airlines will use big data to avoid dangerous turbulence. In this case, the family got home safely but Mrs Taylor told the BBC she was given short shrift when the raised the matter with TUI and was initially offered a goodwill gesture of £30. But TUI, which said seat problem was due to a last-minute aircraft change,  subsequently offered the family a full refund of  £1300 after being contacted by BBC’s Rip Off Britain: Holidays. The UK Civil Aviation Authority, which is looking into the matter, told the broadcaster that while passengers are allowed to sit in crew seats under certain conditions, they must not be left unseated during any stage of the flight.