Airworthiness Directives; Jetstream Aircraft Limited HP137 Mk1 and Jetstream Series 200 Airplanes

This amendment supersedes Airworthiness Directive (AD) 83-05- 01, which currently requires the following on Jetstream Aircraft Limited (JAL) HP137 Mk1 and Jetstream series 200 airplanes: repetitively inspecting the wing lower skin panels at the main gear bay cutouts for loose or damaged rivets and cracks, replacing loose or damaged rivets, and repairing any cracked wing lower skin panel. The Federal Aviation Administration's policy on commuter-class aircraft is to eliminate or, in certain instances, reduce the number of certain repetitive short-interval inspections when improved parts or modifications are available. The proposed action would require reinforcing the wing lower skin at both the landing gear cutouts at Wing Station (WS) 115 and the undercarriage bay cutouts at WS 60 and WS 90, as terminating action for the repetitive inspections that are currently required by AD 83-05-01. The actions specified in the proposed AD are intended to prevent wing damage caused by cracks or loose or damaged rivets in the wing lower skin panels, which, if not detected and corrected, could result in structural damage to the point of failure.