Mitsubishi Aircraft and Phoenix-based Mesa Airlines have signed a memorandum of understanding covering a potential firm order for 50 SpaceJet M100 regional jets and purchase rights on another 50, the Japanese manufacturer announced Thursday evening at the Regional Airline Association convention in Nashville, Tennessee. In a statement, Mesa said it would operate the jets under capacity purchase agreements with partner major airlines starting in 2024. 

The contract with Mesa represents a commercial breakthrough for the M100, an extensively revamped iteration of a 76-seat concept Mitsubishi had called the MRJ70. Scheduled for certification in 2023, the M100 would fly to a range of 2,000 nm, while seating 76 passengers in a three-class configuration, requiring Mitsubishi to seek advances to the airframe to lower weight—including the addition of new lightweight materials such as composites and different metallic alloys. Most significantly, the airplane would meet the 86,000-pound mtow takeoff weight limit specified in the pilot union labor contracts at all three major U.S. airlines.

Mitsubishi considers the U.S. by far the biggest market for the SpaceJet, and when development began more than a decade ago most company executives expected scope clauses at the major airlines to relax enough to allow operation of the MRJ90—since rebranded the M90—at their regional affiliates. Market conditions and the appetite by mainline airline executives to confront their pilot groups over the issues have changed, however, and Mitsubishi’s customers have clearly indicated they don’t plan to further push for concessions by the time contract-amendable dates usher in the start of the next round of collective bargaining, soon after the turn of the decade.

The situation has essentially limited the 92-seat M90’s future customer base to markets outside the U.S., where launch customer All Nippon Airways and Japan Airlines can operate unencumbered by scope clauses. Plans call for first delivery of the M90 to ANA by the middle of next year.