As a legacy of there being no inspection specific to an in-flight pitch disconnect, there is potential for other ATR aircraft to have sustained an in-flight pitch disconnect in the past and be operating with undetected horizontal stabiliser damage.
The ATSB considers that the action taken by ATR addresses this safety issue.
In July 2016, ATR issued an All Operators Message (AOM: 42/72/2016/13 issue 1) to advise of stabiliser damage found during a scheduled maintenance check. Although the origin of this damage was not yet identified, ATR advised that it might be related to aircraft used beyond normal operation limitations (including but not limited to the combination of in-flight dual inputs, a pitch disconnect and large opposite elevator deflection at high speed).
ATR recommended in the AOM that operators perform a one-time inspection of the horizontal to vertical stabilizer junction as per the instructions in SB ATR42-55-0015 or ATR 72-55-1008 at the next convenient opportunity, no later than 6 months from release of the AOM.
