Boeing discovered cracks in the structure of the 777X during its first test flight on August 19. The company said it would ground its test fleet to replace the faulty part and find out the cause of the problem. The company said the part is a structural part between the engine and the fuselage, and it has notified federal regulators and customers of the situation. Boeing is reportedly on order for 540 new aircraft, with deliveries scheduled to begin in 2025. It is not clear whether the problem will affect the delivery date of the aircraft.