Flybe's collapse "will likely be the first of many in 2020," said James Goodall, transport analyst at Redburn.
"We expect that the demand destruction caused by Covid-19 accelerated its demise and we believe further airline bankruptcies should be expected in the coming months."
Airlines could lose $63bn to $113bn in revenue from the slump in passenger traffic globally this year, the International Air Transport Association (IATA) said on Thursday. Last month, it had predicted losses of $29bn.
Demand has plummeted, not just from holidaymakers, but from corporate travel as firms restrict business trips for employees and conferences are postponed.
"There will be a significant increase in airline casualties in this scenario," said Michael Duff, managing director at The Airline Analyst.
Many airlines have introduced cost-cutting measures such as asking staff to take unpaid leave and pay cuts as planes are grounded.
Emirates has asked workers to take unpaid leave for up to one month, while Cathay Pacific asked staff to take three weeks of unpaid leave.