AD NUMBER: PL2008-22-53
SUBJECT: Airworthiness Directive PL2008-22-53 SUMMARY: This superseding
Emergency Airworthiness Directive (EAD) is prompted by 4
occurrences on the MD900 helicopters with failed left Vertical
Stabilizer Control System (VSCS) adapter tubes where the vertical
stabilizer became uncontrollable, resulting in reduced yaw control
of the helicopter.
There were no injuries, but in one occurrence, due to the high
speed quick yaw, the helicopter lost a window and a door.
The actions specified by this EAD are intended to prevent a
reduction of yaw control and subsequent loss of control of the