Which statement is true about Part 121 Operations?

• A. MTOW greater than 8618 kg
• B. Air Transport Operations for Smaller Aircraft
• C. Operational pax seating capacity <= 9
• D. MTWO <= 8618 kg

Answer: (A)

Part 121 operations cover air carrier services using larger aircraft, and the defining criterion is having a maximum takeoff weight above a specific threshold. In this context, that threshold is 8,618 kg (about 19,000 lb). When an aircraft’s MTOW exceeds this amount, it falls under Part 121 rules, which govern scheduled airline operations and impose stricter requirements due to the size and complexity of the operation. The other statements don’t fit because smaller aircraft aren’t governed by Part 121 (they fall under Part 135 or Part 91), seating capacity for Part 121-operated aircraft is typically well above 9 seats, and the term MTWO is not the correct metric here and the direction of the inequality matters.