The carrier is expanding the technology to its international widebody fleet.
The investment firm has until the end of this week to secure a deal.
The aircraft is expected to enter service next year.
The head of Airlines For America is expected to testify.
The AFA-CWA cited “seriously delayed bargaining” and “outrageously low economic proposals” from the airline’s management.
Carriers were stung by higher fuel prices stemming from the war in Iran.
The start-up carrier applied for a foreign air carrier permit and exemption authority in May.