Complex sentence: More than half of all passengers travelling by air in the UK currently travel via the five London area airports, though regional airports have experienced the most growth in recent years, due to the success of'no-frills' airlines over the last decade.
Split into simpler sentences: More than half of all passengers travelling by air in the UK currently travel via the five London area airports. Regional airports have experienced the most growth in recent years, due to the success of'no-frills' airlines over the last decade.