The Boeing 737 MAX 10 has an impressive and strong customer base, including United Airlines, Ryanair, American Airlines and Delta Air Lines. However, recent years have not been kind to the largest 737 MAX variant, which has suffered from a hefty backlog. Certification Problems Are The 737 MAX 10's Main IssueCredit: ShutterstockBoeing has given prospective customers a huge reason to not choose its MAX 10: certification issues. Aircraft Range Airbus A321neo 3,400 nautical miles (6,297 km) Airbus A321LR 4,000 nautical miles (7,408 km) Airbus A321XLR 4,700 nautical miles (8,704 km) Boeing 737 MAX 7 3,800 nautical miles (7,040 km) Boeing 737 MAX 8 3,500 nautical miles (6,480 km) Boeing 737 MAX 9 3,300 nautical miles (6,110 km) Boeing 737 MAX 10 3,100 nautical miles (5,740 km)The A321XLR can remain in the skies for an incredible 11 hours. Related All The Airlines Waiting For Boeing To Certify The 737 MAX 10 With regulatory obstacles pending and airlines awaiting final approval, all eyes are on Boeing's largest single-aisle aircraft, the 737 MAX 10.