Scandinavian airline SAS filed for bankruptcy in the United States in order to accelerate its restructuring plans, warning a strike by its pilots had adversely affected its liquidity and financial position.
Half of its flights were cancelled due to the industrial action after wage negotiations between the carrier and its pilots collapsed.
SAS said it had brought forward plans to restructure its finances following the strike, with plans to reduce their salaries as part of the airline's restructuring the reason for them walking out.
In Chapter 11 bankruptcy a company can restructure its debts while continuing to operate under court supervision.
SAS said talks to raise US$756mln were "well advanced" to enable it to continue its immediate operations.
Aeromexico and Philippine Airlines have also renegotiated contracts and financial arrangements with key suppliers under Chapter 11 protection.
As air travel rebounded in recent months, airlines and airports - which shed thousands of jobs during the pandemic - have struggled to keep pace.
As a result of the pandemic, SAS cut 5,000 jobs - 40% of its workforce - in 2020.
After a series of flight cancellations and disruptions, EasyJet's chief operating officer resigned on Monday.