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

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 left and right wing upper and lower spar doublers for cracks; replace any cracked parts; and incorporate a modification kit. This 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, including incidents where the fatigue cracking occurred on airplanes with less than 500 hours time-in-service (TIS). The actions specified by this AD are intended to detect and correct cracks in the wing spars, which could result in the wing separating from the airplane with consequent loss of control.