171. A 100-hour inspection was due at 3302.5 hours. The 100-hour inspection was actually done at 3309.5 hours. When is the next 100-hour inspection due?

Title 14 § 91.409 Inspections.

The FAA allows for a 100-hour inspection to be exceeded by up to 10 hours while en route to a location where the inspection can be performed. However, this excess time must be subtracted from the next 100-hour interval.

The 100-hour inspection was due at 3302.5 hours. It was actually performed at 3309.5 hours, meaning the inspection was overflown by 7 hours. This 7-hour overage must be subtracted from the next 100-hour period.

Next inspection due: 3309.5 hours (current time) + 100 hours — 7 hours = 3402.5 hours.