Which of the following is NOT a condition for Subpart 121.Z to apply?

• A. Operating single-engine aircraft is a condition.
• B. Seating capacity more than 9 is a condition.
• C. MTOW 8618 kg or less is a condition.
• D. MTOW greater than 8618 kg is not a condition.

Answer: (D)

Subpart 121.Z applies only when the aircraft meets a specific set of gating criteria. The weight limit is the boundary for applicability: the aircraft must have a maximum takeoff weight of 8,618 kg or less. It must also be single-engine and have seating capacity greater than nine. Describing MTOW as greater than 8,618 kg is not a condition that brings Subpart 121.Z into effect; in fact, exceeding the weight limit disqualifies the subpart. So the other criteria are the ones that must be met for Subpart 121.Z to apply, while MTOW above 8,618 kg is an exclusion.