Airworthiness Directive: 123
Date: June 14, 2001
Subject: S-12S Flow Fence 
Compliance: Mandatory 
Models Effected: All S-12S with Warp Drive Propellers
Cost: None
Parts Provided: Foam Rubber
Builder Supplied Parts: Super Glue

S-12S aircraft equipped with the 912 and 912S engine have the potential of a rough start.  When this occurs, it is possible for the tip of the propeller to contact the flow fence.

Please take the following steps to prevent damage to the flow fence and propeller:

1. Check if your aircraft has a 2" propeller spacer installed.  A 2" spacer is required.

2. Using a high-speed cutting tool, like a Dremel®, , cut out a notch as shown in Figure 1.  Drill holes in locations shown to prevent cracking.

FIGURE 1



3. Take the foam rubber provided, glue together the two pieces of foam to form a single block and insert into notch.  Use super glue to secure in   place by squirting small amounts between the foam rubber and sheet metal.  See Figure 2.

FIGURE 2

Parts required:  

DESCRIPTION                                     PART NUMBER      QTY                  5/8" X  2" X 1"  Black Foam Rubber           ----------                 2

Thank you for your attention to this matter. Hopefully we have not inconvenienced you to any great degree.

Fly safe.