An air taxi aircraft's last required 100-hour inspection was completed at a recorded tachometer time of 1,200.0 hours, making the next 100-hour inspection due at 1,300.0 hours. The aircraft is now at 1,301.5 hours, and the operator wants to fly it 3.5 hours to reach a maintenance facility that can perform the inspection. Is this flight permitted, and when is the next 100-hour inspection due?
- APermitted; the flight is within the 10-hour overflight allowance, and the next inspection is due at 1,400.0 hours
- BPermitted; the flight is within the 10-hour allowance, and the next inspection is due at 1,405.0 hours
- CNot permitted because the aircraft has exceeded the 100-hour limit by more than 1 hour
- DNot permitted; the aircraft is already overdue and must not be flown
Show answer & explanationAnswer & explanation
Correct answer: A. Permitted; the flight is within the 10-hour overflight allowance, and the next inspection is due at 1,400.0 hours
14 CFR 91.409(c) allows the 100-hour limit to be exceeded by not more than 10 hours to fly the aircraft to a place where the inspection can be done. Here, the aircraft is 1.5 hours over at departure, and the 3.5-hour flight brings total overflight to 5.0 hours (1,301.5+3.5=1,305.0), which is within the 10-hour allowance. Importantly, the excess time is counted toward the next 100 hours, so the next inspection remains due at the original due date plus 100 hours (1,300.0+100=1,400.0), not based on the point at which the aircraft actually landed.
Why the other options are wrong
- B. Incorrectly bases the next due time on the actual flight time flown (1,305.0) instead of the original due point.
- C. 1.5 hours over is well within the allowable 10-hour overflight margin.
- D. Overflight up to 10 hours over the limit is explicitly permitted by regulation.
100-Hour Overflight Allowance
14 CFR 91.409(c) permits exceeding the 100-hour inspection limit by up to 10 hours to reach a place of inspection, but the excess counts toward the next 100 hours due.
- Applies only when flying to a maintenance facility for the inspection.
- Maximum overflight allowed is 10 hours total.
- Next inspection is still due 100 hours after the original due point, not the actual landing time.
Memory trick: "Ten extra hours to find a wrench, but the clock doesn't budge an inch."