Flight Controls

FAA Aviation Safety SPECIAL AIRWORTHINESS INFORMATION BULLETIN SAIB: CE-11-43 SUBJ: Flight Controls Date: July 6, 2011 This is information only. Recommendations aren’t mandatory.

Introduction

This Special Airworthiness Information Bulletin (SAIB) advises you of an airworthiness concern regarding possible interference with flight control due to loose objects in American Champion Aircraft Corporation (ACAC) Models 7EC, 7ECA, 7GCAA, 7GCBC, 7KCAB, 8KCAB, & 8GCBC airplanes.

At this time, this airworthiness concern is not considered an unsafe condition that would warrant an airworthiness directive action under Title 14 of the Code of Federal Regulations (14 CFR part 39).

Background

This SAIB resulted from an incident where an American Champion Model 8KCAB (Decathlon) airplane experienced a partial loss of elevator control while conducting aerobatic maneuvers. The pilot was able to make a hard landing, using power, which resulted in a propeller strike. Inspection of the airplane revealed that the retention pin and ring from the emergency door jettison handle was lodged between the elevator bellcrank and the fuselage, thus limiting elevator travel. It is believed that the emergency door jettison pin and ring had become dislodged, fallen between the floorboard and the side wall of the fuselage, and then worked its way back to the elevator bellcrank during aerobatic maneuvers.

A search of accident/incident and service difficulty databases turned up two additional control jamming events for American Champion model 8KCAB airplanes. The first involved a momentary jam of the aileron due to a loose emergency door retention pin and ring in the airplane belly (similar to the elevator jamming event that initiated this SAIB). Another model 8KCAB elevator jam was reported as the result of a loose seat belt buckle component that had migrated to the empennage of the airplane.

American Champion has issued three service letters. The first is directed specifically at the emergency door jettison retention pin and ring.  Service letter 434, dated June 9, 2011, provides instructions on how to tether the emergency door jettison pin, such that the pin may be removed for emergency egress, yet the pin remains tethered to the door, thus preventing it from becoming a piece of foreign object debris that could interfere with a flight control.  Service Letter 435, dated June 9, 2011, provides recommended inspection procedures of the fuselage belly at 100-hour or annual inspections for loose items.  Service Letter 436, dated June 10, 2011, provides for floorboard extensions in the left and right forward cabin. The extensions provide a closer fit with the cabin sidewalls and therefore lessen the likelihood of a loose object in the cabin migrating to the airplane belly, where it could cause a flight control interference or jam.

1

2 Recommendations

We recommend that all that ACAC model airplanes identified in the introduction above complete the repetitive inspection procedures in American Champion Service Letter 435 as well as the one time procedures in Service Letters 434 and 436.

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].

For Related Service Information Contact

To obtain copies of American Champion service letter numbers 434, 435, & 436, contact American Champion Aircraft Corporation, P.O. Box 37, 32032 Washington Ave. – Hwy. D, Rochester, WI 53167; or visit their website at www.amerchampionaircraft.com, select “Technical” and scroll down to the service letter number you wish to view or print.