An aircraft is used exclusively to give flight instruction for hire and has accumulated 97 hours since its last 100-hour inspection. The nearest facility capable of performing the inspection is 2 hours away by flight time. According to 14 CFR 91.409(a), what is the mechanic's/operator's correct course of action?
- AThe aircraft must be grounded immediately at 97 hours until the inspection is completed
- BThe aircraft may be flown up to 10 hours past the 100-hour limit to reach a place where the inspection can be performed, and that overflight time counts toward the next inspection interval
- CThe 100-hour requirement only applies to aircraft over 12,500 pounds, so this aircraft is exempt
- DThe aircraft may continue operating indefinitely as long as the pilot logs the overdue condition
Show answer & explanationAnswer & explanation
Correct answer: B. The aircraft may be flown up to 10 hours past the 100-hour limit to reach a place where the inspection can be performed, and that overflight time counts toward the next inspection interval
14 CFR 91.409(a) allows an aircraft to exceed the 100-hour limit by not more than 10 hours if necessary to reach a place where the inspection can be performed; any time flown in excess of 100 hours is deducted from the next 100-hour interval.
Why the other options are wrong
- A. Incorrect; the regulation specifically permits a limited overflight allowance to reach maintenance.
- C. Incorrect; the 100-hour rule applies based on use for hire/instruction, not aircraft weight.
- D. Incorrect; there is no indefinite extension, only the 10-hour allowance.
100-Hour Inspection Overflight Allowance
14 CFR 91.409(a) permits an aircraft due for a 100-hour inspection to fly up to 10 additional hours to reach a facility that can perform the inspection, with that excess time counted against the next inspection interval.
- Applies to aircraft used for hire or flight instruction for hire
- Maximum 10-hour overflight allowance
- Excess hours are subtracted from the next 100-hour interval
- Inspection must occur before further flight except to reach the maintenance location
Memory trick: 'Ten more to get her fixed' — 10 extra hours allowed to reach the shop.