Frontier and Spirit Airlines will once again try to merge, only months after the Biden administration won a key antitrust court battle to block an attempt by JetBlue to buy Spirit. A combination of the two ultra-low-cost carriers would produce the country’s fifth largest airline,

Frontier Airlines is attempting for a second time to merge with the now bankrupt Spirit Airlines, which declared bankruptcy late last year as budget airlines struggle.

Frontier said in a release that it has met with Spirit’s board and executives since it made its proposal this month.