The COVID-19 pandemic has had a significant impact on the aviation industry due to travel restrictions and a slump in demand among travellers. Significant reductions in passenger numbers have resulted in flights being cancelled or planes flying empty between airports, which in turn massively reduced revenues for airlines and forced many airlines to lay off employees or declare bankruptcy. Some have attempted to avoid refunding cancelled trips to diminish their losses. Airliner manufacturers and airport operators have also laid off employees.