Six airlines in the UK, including Wizz Air, British Airways and Tui, collectively owe passengers £4.5m ($5.9m) in unpaid court claims, according to consumer association Which? Wizz Air accounted for more than half of the total, with £2.2m owed across 1,601 judgements. The Civil Aviation Authority’s AviationADR refund scheme was described as “failing” by Which?, causing a backlog of cases, with thousands of claims outstanding. The scheme was introduced in 2016 to allow passengers to access their entitlement to refunds and expenses when flights are delayed or cancelled.