EASA AD US-2018-23-09
Stabilizers - Horizontal Stabilizers - Inspection
Airworthiness Directive 2018-23-09 is a final rule issued by the Federal Aviation Administration addressing The Boeing Company Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes. It mandates inspections of horizontal stabilizers to detect cracks in the rear spar upper chord caused by galvanic corrosion due to a manufacturing oversight involving missing protective finishes on certain bushings.