Airline debt has jumped 23% since 2020 to $340 billion, according to data compiled by Bloomberg. So far this year, sales of bonds and loans to global airlines have reached about $63 billion.

The debt growth is further evidence that the industry faces a bumpy road ahead, with many border restrictions still in place and the summer holiday season in the United States and Europe It's coming to an end.

EasyJet and Japan Airlines announced new plans to raise funds this month to help them cope with the protracted pandemic.

Susanna Streeter, senior investment and markets analyst at Hargreaves Lance Down, said the spread of the delta variable could lead to other countries imposing stricter quarantine rules on visitors. .

Many airlines are tapping the bond market once again, while strong bond sales show investors' willingness to provide significant funding to the industry.

EasyJet has raised $400m in new debt and £1.2bn ($1.7bn) in equity. Funding will provide a back-up to weather a slow winter and position the carrier for a temporary recovery in leisure travel.

Japan Airlines has secured nearly 300 billion yen ($2.7 billion) in new financing through bonds and subordinated loans. Japan Airlines said the money will also be used to modernize its fleet by purchasing Airbus 350-1000 planes to become the flagship of the international airline.

Australia's Qantas Airways also announced plans to sell the bonds.