What is the difference between an Annual inspection and a 100-hour inspection for small aircraft?

• A. Both inspections are optional.
• B. A 100-hour inspection is required for all aircraft.
• C. An annual inspection is legally required for all aircraft; a 100-hour inspection is required if the airplane is used for hire or flight instruction; both require a certified mechanic.
• D. There is no legal difference between the two inspections.

Answer: (C)

The question tests understanding of two different FAA-mandated inspection triggers. An annual inspection is a calendar-based requirement that applies to every civil aircraft, ensuring a comprehensive check of airworthiness regardless of usage. A 100-hour inspection is time-based and only comes into play if the airplane is used for hire or for flight instruction. If the aircraft is not used commercially, the 100-hour rule doesn’t apply, though the annual still does. For both inspections, a certificated mechanic must perform the work and sign off in the logbook, certifying the aircraft as airworthy. This combination—universal annuals versus conditional 100-hour checks, plus the need for a certified mechanic—is what makes the stated answer correct.