AD NUMBER: 2007-17-09
MANUFACTURER: Mitsubishi
SUBJECT: Airworthiness Directive 2007-17-09
SUMMARY: We are adopting a new airworthiness directive (AD) to supersede 93-07-11 and AD 94-04-16, which apply to certain Mitsubishi Heavy Industries MU-2B series airplanes.

AD 93-07-11 and AD94-04-16 currently require you to reduce the maximum deflection of the elevator nose-down trim to a 1-degree to 3-degree range. When the above AD actions were issued, there was no associated elevator trim indicator change.

Without such change, the trim reaches the maximum nose-down limit and the indicator still shows additional nose-down trim available.

In attempting to force additional nose-down trim, pilots have manually jammed the trim system preventing subsequent electric trim changes until the pilot manually freed the trim wheel.

Consequently, this AD retains the actions from AD 93-07-11 and AD 94-04-16 and adds the action of modifying the elevator trim indicator scale dial to be consistent with the reduced elevator trim capability.

We are issuing this AD to prevent the above scenarios from occurring with consequent loss of control.

FMI: www.faa.gov/regulations_policies/airworthiness_directives/