48-28-01 TEMCO: Applies to All Models GC-1A and GC-1B Aircraft.
I. Inspection required at each 20 hours operation until compliance with item II is made.
Cracks are occurring in the last bulkhead (Station 185) of the fuselage at the bottom rudder hinge and stop fitting, and the bulkhead must be inspected for such cracks. If cracks are found, a repair must be made in accordance with item II.
II. Compliance required not later than September 1, 1948.
To preclude the possibility of a structural failure in the rear bulkhead of the fuselage, at the bottom rudder hinge and stop, a steel reinforcement must be made as follows:
1. If cracks are found in the bulkhead drill No. 50 (0.07 diameter) check holes at end of each crack.
2. Fabricate and install a steel reinforcement fitting as defined in TEMCO Drawing 11-213-5074.
The Texas Engineering and Manufacturing Co., Inc., will furnish free of charge the steel reinforcement fitting described in item 2.
(TEMCO Customer Service Maintenance Bulletin No. 26 covers this same subject.)