SAIB CE-04-83 —

1 SPECIAL AIRWORTHINESS INFORMATION BULLETIN

Aircraft Certification Service Washington, DC

U.S. Department of Transportation Federal Aviation Administration

CE-04-83 September 9, 2004 www.faa.gov/certification/aircraft This is information only. Recommendations aren’t mandatory.

Introduction

This Special Airworthiness Information Bulletin (SAIB) alerts you, registered owners and operators of American Champion Aircraft Corp. (Aeronca, Bellanca, Champion) 7GCB, 7GCBC, and 8GCBC airplanes, all serial numbers, of possible flap cable fraying. Undetected fraying of the flap cable could lead to cable failure and partial loss of deployed flaps.

Background

We have Service Difficulty Reports (SDRs) on file regarding flap cable fraying, part number (P/N) 1-9023, and pulley binding/seizing, P/N 1-2395, in the wing roots on the above mentioned airplanes. American Champion has analyzed the problem and determined that flap cable forces are transmitted over such as small area of the pulley that, without frequent lubrication, pulley and cable wear can occur quickly.

American Champion has issued Service Letter (S/L) 424, dated March 8, 2004, to address the airworthiness concern. This S/L specifies inspecting the wing root flap pulleys and cables for wear and lubrication every 50 hours time-in-service (TIS) for aircraft with heavy or prolonged flap usage and every 100 hours TIS or annual (whichever is least in hours) for aircraft with low flap usage.

American Champion currently changed the production of the affected airplanes to incorporate a larger diameter flap pulley, P/N 11-0968, to reduce pulley and cable wear. The larger flap pulley allows for standard flap and pulley inspection intervals (100 hours TIS or annual, as applicable without regard to flap usage). The S/L also states that field aircraft that are modified to incorporate the larger pulley, P/N 11-0968, should also install a new pulley bracket, P/N 2-2297.

The affected aircraft models and serial numbers, the service intervals, and the optional field modification to the larger flap pulley are all covered in the S/L.

2 Recommendation

We recommended that you complete American Champion S/L 424 within the next 90 days.

This Service Letter Can Be Obtained From the Following Website

http://www.amerchampionaircraft.com/tech/SL424.doc

For Further Information, Contact

Wesley Rouse, Aerospace Engineer, FAA, Chicago Aircraft Certification, 2300 E. Devon, Des Plaines, IL 60018; phone (847) 294-8113; email: [email protected].