AD 2002-21-05 67 FR 64039

This amendment adopts a new airworthiness directive (AD) that applies to certain REVO, Incorporated (REVO) Models Lake LA-4, Lake LA- 4A, Lake LA-4P, Lake LA-4-200, and Lake Model 250 airplanes. This AD requires you to inspect the upper and lower wing spar doublers and angles for cracks at a certain time after the incorporation of Modification Kit B-79 or FAA-approved equivalent, replace any cracked wing spar doubler or angle, and report the results of the inspection to the Federal Aviation Administration (FAA). The kit modification consists of installing a doubler kit to give the spar an adequate fatigue life. This AD is the result of an incident of a crack found at the most outboard wing attachment fitting hole on one of the affected airplanes with the modification incorporated. The actions specified by this AD are intended to prevent wing spar failure caused by cracks in the wing spar doublers or angles, which could result in the wing separating from the airplane with consequent loss of control.