Airworthiness Directives; Alexandria Aircraft LLC Airplanes

We are superseding Airworthiness Directive (AD) 75-20-06 for certain Alexandria Aircraft LLC (type certificate previously held by Bellanca Aircraft Corp., Viking Aviation, Inc., and Bellanca, Inc.) Models 14-19-3A, 17-30, 17-30A, 17-31, 17-31A, 17-31ATC, and 17-31TC airplanes. AD 75-20-06 required repetitively inspecting the aft fuselage structure near the top of the vertical side tubing, which connects the horizontal stabilizer carry-through to the upper fuselage longeron, for cracks and installing the manufacturer's service repair kit as a terminating action for the repetitive inspections to repair any cracks found. Since we issued AD 75-20-06, we have determined that installing the service kit has not prevented cracks from occurring. We have also determined that all affected airplane serial numbers should be included in the Applicability section. This AD requires continued repetitive inspections of the aft fuselage structure near the top of the vertical side tubing for cracks and making all necessary replacements of cracked parts. This AD also adds additional serial number airplanes to the Applicability section. We are issuing this AD to correct the unsafe condition on these products.