Summary
The FAA proposes to supersede Airworthiness Directive (AD) 2021-12-10, which applies to certain Leonardo S.p.a. Model AB139 and AW139 helicopters. AD 2021-12-10 requires installing a placard on the primary stretcher unit. Since the FAA issued AD 2021-12-10, Aerolite (the manufacturer of the stretcher unit), developed a modification of the primary stretcher unit to improve its structural properties. This proposed AD would require the installation of a certain placard depending on the configuration of the primary stretcher unit. The proposed AD would also require revising the existing rotorcraft flight manual (RFM) for the helicopter. This proposed AD would also revise the applicability to only include Leonardo S.p.a. Model AB139 and AW139 helicopters, modified by FAA Supplemental Type Certificate (STC) SR04384NY. The FAA is proposing this AD to address the unsafe condition on these products.