Skip to content
Vincony — fast, managed web hosting for your next site
The Pilots Desk
US-FAA14 CFR 121.1115

Limit of validity

Read the official rule

This regulation requires Part 121 air carriers operating certain large turbine transport aircraft to incorporate a "Limit of Validity" (LOV) into their maintenance programs. The LOV establishes a maximum age or usage limit for the airplane's structure based on fatigue and damage tolerance analysis—essentially a point beyond which the aircraft cannot be operated unless additional engineering analysis extends that limit.

The rule applies primarily to transport category, turbine-powered airplanes over 75,000 pounds with type certificates issued after January 1, 1958, plus certain lighter aircraft requiring an LOV under design regulations. Carriers must include an FAA-approved LOV in their Airworthiness Limitations Section by dates specified in the regulation's tables. If no approved LOV exists by the compliance date, operators must use a default LOV from the regulation's tables.

To operate beyond an LOV, carriers need an extended LOV approved under separate regulations addressing widespread fatigue damage, with Principal Maintenance Inspector approval required for all program revisions.

*This is a plain-English summary for study only. The official 14 CFR text on this page is controlling — always read the current regulation and consult a CFI.*

This is an original plain-English explanation for training and reference, not legal advice and not for navigation. Always rely on the current official rule linked above. Last reviewed June 20, 2026.