The FAA proposes to adopt a new airworthiness directive AD for certain ATRGIE Avions de Transport Rgional Model ATR42-500 and ATR72-212A airplanes. This proposed AD was prompted by a report of the possible use of improper material during the manufacturing of vertical stabilizer to horizontal stabilizer junction fittings. This proposed AD would require inspections of affected parts applicable repairs and eventual replacement of certain affected parts as specified in a European Union Aviation Safety Agency EASA AD which is proposed for incorporation by reference IBR. The FAA is proposing this AD to address the unsafe condition on these products.