Summary
This document revises an earlier proposed airworthiness directive (AD), applicable to certain Jetstream BAe Model ATP airplanes, that would have required repetitive inspections to detect damage of the antenna mounting reinforcing plates and surrounding fuselage skin. If any damage was detected, the proposed AD would have also required replacement of the reinforcing plate with a new reinforcing plate and/or repair of the surrounding fuselage skin, which would have terminated the repetitive inspection requirements. That proposal was prompted by reports of corrosion found at the antenna reinforcing plates, which was caused by ingress of water at the plates. This action revises the proposed rule by expanding the inspection area. The actions specified by this proposed AD are intended to prevent such corrosion, which could result in reduced structural integrity of the fuselage pressure vessel.