AD Issued on Grob Astir CS gliders, 2006-17-02; Horizontal tail locking bolt.
This AD affects Model G102 ASTIR CS sailplanes, serial numbers 1001 through 1536, which are certificated in any category. It supercedes AD 84-09-05, which required you to install a modified spherical locking bolt and nut in the forward horizontal stabilizer connection to the vertical stabilizer and install new locking pins in the aft connecting plate for the horizontal stabilizer.
Since AD 84- 09-05, fatigue cracks were found in the modified spherical locking bolt. Consequently, this AD requires you to replace the modified spherical locking bolt, the retaining pins (collar bolts), and associated hardware; add a life limit on the spherical locking bolt and the retaining pins; and repetitively inspect the front and rear horizontal stabilizer attachment. This is issued to prevent cracks in the spherical locking bolt, which could result in failure of the horizontal stabilizer connection. This failure could lead to loss of control. The repetitive inspections must occur annually or not to exceed each 100 hrs. time in service.
This AD becomes effective on September 22, 2006. Compliance must be achieved within 90 days of the effective date. Life limit is ten years on the new parts.
Govt. Liaison Committee