Aileron Pulley Guard Modifications

Listed below are summaries of ANOR 3/13/03 page 2, Step 48 that replaces Section IX, page 174 and the Mandatory Service Bulletin 47 (9/18/2001).

ANOR 3/13/03 page 2, Step 48 replaces Section IX, page 174

1. Bend guard strap around the bolt head to prevent the guard from rotating.
2. Each cable guard using cotter pins, clevis pins, or other welded structure must not exceed a maximum clearance of 1/16” from the edge of the pulley.

Service Bulletin 47  (9/18/01)  - Mandatory

1. Use material thickness of 0.025 inches (not 0.020 per the manual) to fabricate new pulley guards with clearance of 0.05 at the sides and 0.04 at the outer edge of the pulley(s).
2. Clearance between pulley and pins can be corrected by drilling a new hole or by placing a thin wall sleeve over the clevis or cotter pin.
3. If pulleys are too far away from a welded bracket guard (lower outboard flap pulleys) you can rivet a thin shim of suitable material onto the bracket.

Check the clearance of all pulley guards with a piece of shim stock.

Here is what I did to satisfy both:

1)  Increased the thickness of the material to 0.050 inches instead of the recommended 0.025 inches for all of the fabricated guards.

2)  For the Aileron pulley guards, I extended the top leg of each strap and bent it up against the wing spar rather than the bolt head to prevent the strap from rotating.  I felt that since the wing will be closed and these guards will not be easily accessible, then they must be made so that they will never be able to rotate.  Also, the torque on the nut/bolt will not have to be so great.  For those pulley guards inside the cage (that are easily accessible), I bent the guards up against the bolt heads per the ANOR.

Heavy Duty Pulley Guard Straps Bent Up Against the Wing Spar

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