AD FAA-2018-0271

We are superseding Airworthiness Directive (AD) 2016-13-06, which applied to certain Saab AB, Saab Aeronautics Model 340A (SAAB/ SF340A) and SAAB 340B airplanes. AD 2016-13-06 required a revision of the applicable airplane flight manual (AFM), repetitive inspections of the horizontal stabilizer de-icing boots, and applicable corrective actions. This AD continues to require a revision of the applicable AFM, repetitive inspections of the horizontal stabilizer de-icing boots, and applicable corrective actions. This AD also requires replacement of single stitched de-icing boots with improved double stitched boots, and re-identification of the modified horizontal stabilizer leading edge. This AD was prompted by reports of ruptured horizontal stabilizer de- icing boots. We are issuing this AD to address the unsafe condition on these products.