SAIB CE-04-03 —

1 SPECIAL AIRWORTHINESS INFORMATION BULLETIN

Aircraft Certification Service Washington, DC

U.S. Department of Transportation Federal Aviation Administration

No. CE-04-03 October 8, 2003 We post SAIBs on the internet at www.airweb.faa.gov This is information only. Recommendations are not mandatory.

Introduction This Special Airworthiness Information Bulletin (SAIB) informs you, a registered owner or operator of certain Cessna Aircraft Company and Reims Aviation (Cessna) 172, 180, and 185 series airplanes (listed below), of the potential for failure of the control yoke assembly. This failure could cause loss of pitch and potential loss of aileron control of the airplane.

Cessna Aircraft Company 172E 172K 172Q R172J 180K 172F 172L R172E (T41) R172K 185D 172G 172M R172F (T41) 172RG 185E 172H 172N R172G (T41) 180H A185E 172I 172P R172H (T41) 180J A185F

Reims Aviation S.A. Cessna F172E Cessna F172H Cessna F172M Cessna FR172E Cessna FR172H Cessna F172F Cessna F172K Cessna F172N Cessna FR172F Cessna FR172J Cessna F172G Cessna F172L Cessna F172P Cessna FR172G Cessna FR172K

Background We have received reports that certain Cessna 172, 180, and 185 airplanes experienced a failure in the control yoke assembly caused by corrosion due to moisture ingress. This failure could cause loss of primary pitch control, and if the failure is above the pivot point, potential loss of aileron control. The corroded yoke is then susceptible to failure under normal pilot loads. The design of the yoke leaves a closed tube section below the pivot point. This closed area can collect moisture in some circumstances that can lead to corrosion and potential failure of the unit. The control yoke has been redesigned in production to eliminate the potential for moisture collection.

As a result of these failures, Cessna has issued service bulletin (SB) SEB01-3, Control Yoke Inspection, which provides instructions for removing the control yoke assembly, inspecting the base of the yoke, and performing corrosion treatment of the assembly. This SB contains a detailed listing of the applicable airplanes and actions to remove the yoke and inspect the base of the assembly by drilling an access hole. Any interior corrosion beyond a thin film calls for an ultrasonic inspection from three inches above the pivot point to the swaged end. Any reading of less than 0.037 inches in thickness is cause for rejection, and replacement of the yoke assembly. Following completion of the SB, they recommend you perform an annual external visual inspection of the yoke.

2 Recommendation The FAA strongly recommends that you incorporate SB SEB01-3, and treat the control yoke with corrosion preventative at the earliest opportunity. At this point we have not made a determination that these procedures should be mandatory. However, we highly recommend these procedures and urge you to give them serious consideration.

For Further Information Contact Chris B. Morgan, Aerospace Engineer, FAA, Wichita Aircraft Certification Office, 1801 Airport Road, Room 100, Mid-Continent Airport, Wichita, Kansas 67209; phone: (316) 946-4154; fax: (316) 946-4107; email: [email protected].

For Copies Of Service Bulletin, Contact Cessna Aircraft Company, One Cessna Blvd., P.O. Box 7704, Wichita, Kansas 67277-7704 phone: (316) 517-6000