Airworthiness Directives; REVO, Incorporated Models Lake LA-4, Lake LA-4A, Lake LA-4P, Lake LA-4-200, and Lake Model 250 Airplanes

Résumé

This document proposes to adopt a new airworthiness directive (AD) that would apply to certain REVO, Incorporated (REVO) Models Lake LA-4, Lake LA-4A, Lake LA-4P, Lake LA-4-200, and Lake Model 250 airplanes. The proposed AD would require inspecting the left and right wing upper and lower spar caps and doublers for cracks, replacing any cracked parts and/or incorporating a modification kit depending on the extent of the damage, and reporting the results of the inspection to the Federal Aviation Administration (FAA). The proposed AD is the result of a report of a fatigue crack found at the second most inboard wing attachment bolt hole on one of the affected airplanes. Similar fatigue cracking has since been reported on seven more of the affected airplanes. The actions specified by the proposed AD are intended to detect and correct cracks in the wing spar caps and doublers, which could result in loss of the wing with consequent loss of control of the airplane.