Cessna Multi-Engine Service Bulletin ME77-34

Full document text

"TAKE YOUR CESSNA HOME FOR SERVICE AT THE SIGN OF THE CESSNA SHIELD" SUBJECT: [flfD Qd] D~ D CJ@ CFU ~ D CFU@ SERVICE LETTER MARKETING DIVISION • CESSNA AIRCRAFT COMPANY WICHITA, KANSAS 67201 • CABLE ADDRESS I CESSCO WICHITA February 13, 1978 TRIM CONTROL SYSTEM ME77 -34 (Supplement #1) AIRCRAFT APPLICABILITY: All Serials of the following Multiengine Aircraft 336,337, T337, P337, 310, 320, 340,401,402,411, 404, 414, 421 The original issuance of Service Letter ME77-34 dated December 23, 1977 provided detailed information for conducting a general inspection of the aileron, elevator and rudder trim systems on the applicable aircraft as noted above. The attached inspection procedures have been revised to correct trim tab deflection information for a certain group of 337 and T337. Areas of change are marked (I) in the left hand margin. * * * * * * (Owner Notification System- No.2) ALL PRICES SUBJECT TO CHANGE WITHOUT NOTICE COPYRIGHT © 1978 CESSNA AIRCRAFT COMPANY CESSNA AIRCRAFT COMPANY ______..........._..........._........._., ..........._........._......._......._......._,_., __________........._........._........._ THERE ARE MORE CESSNAS FLYING THAN ANY OTHER MAKE "TAKE YOUR CESSNA HOME FOR SERVICE AT THE SIGN OF THE CESSNA SHIELD" [fLR)01J0~0CJ@CFU~0CFU@ SERVICE LETTER MARKETING DIVISION • CESSNA AIRCRAFT COMPANY WICHITA, KANSAS 67201 • CABLE ADDRESS I CESSCO WICHITA December 23, 1977 ME77-34 SUBJECT: TRIM CONTROL SYSTEM INSPECTION AIRCRAFT APPLICABILITY: All Serials of the following Multi-Engine Aircraft: 336,337, T337, P337, 310, 320, 340, 401, 402, 411, 404, 414, 421 IMPORTANT To assist Service personnel in maintaining trim control systems on all Cessna Multi-Engine aircraft, the attached inspection procedure has been developed. This procedure provides detailed information for conducting a general in- spection of the aileron, elevator and rudder trim systems and PLACES PARTICULAR EMPHASIS ON THE MOUNTING AND SECURITY OF THE TRIM TAB ACTUATOR AND ASSOCIATED LINKAGE. Because of the importance of trim control systems, a careful inspection (using the attached procedures) is to be made on all Multi-Engine aircraft AT THE NEXT 100 HOURS OR ANNUAL INSPECTION, WHICHEVER COMES FIRST. This inspection can be accomplished quite easily when done as part of a regular aircraft inspection and will insure that this important system is in good operating condition. This detailed trim system inspection procedure will be incorporated into the respective aircraft service manuals and will specify compliance at each 100 hour inspection on Cessna Multi-Engine aircraft. * * * * * * (Owner Notification System - No. 2) ALL PRICES SUBJECT TO CHANGE WITHOUT NOTICE CESSNA AIRCRAFT COMPANY COPYRIGHT © 1977 CESSNA AIRCRAFT COMPANY I I TRIM TAB ACTUATORS, TRIM TABS AND ATTACHING LINKAGE INSPECTION NOTE The following inspection should be accomplished at the next 100 hours or annual inspection whichever occurs first, and is to be repeated every 100 hours thereafter. These instructions are general in nature, for a specific in- stallation, refer to the applicable airplane service manual. Before starting this inspection, turn all electrical power off and remove necessary access panels. 26 January 1978 INSPECTIONS: l. TRIM TAB ACTUATORS USING SNAP RINGS FOR RETENTION a. Inspect the actuator mounting clamps and mounting structure for evidence of damage, cracks and security of installation. Inspect the clamps for proper fit on the actuator, clamps must be firmly seated on the actuator. Inspect snap ring for complete and proper engagement in snap ring groove of actuator. On all airplanes except 336 and 337 series, check that snap ring is properly seated in the positioning slot of the mounting bracket. On 336 and 337 series airplanes, check that snap rings are properly located between the spacers and actuator mounting clamp. Check that mounting clamp bolts or screws (as applicable) are torqued 20 to 25 inch-pounds and apply white lacquer torque putty to bolt for future inspections. Inspect guard block for condition and attachment. NOTE Some installations use two snap rings. The second snap ring should be seated against the end of the mounting bracket. 2. TRIM TAB ACTUATORS- FLANGL MOUNTED a. Inspect the trim tab actuator mounting flange and actuator mounting structure for evidence of damage, cracks and security of installation. Inspect that mounting screws and nuts are torqued 20 to 25 inch- pounds and apply white lacquer torque putty to screws and nuts for future inspections. Inspect guard block or guard pin, as applicable, for condition and attachment. 3. TRIM TAll DEFLECTION (FREE PLAY) CHECK (See Detail at right) a. With the primary control surface and its respective tab in neutral position, restrain the primary control surface and manually deflect the tab at the trailing edge at the point where the actuator push-pull rod is located. Using one pound of force, deflect the tab one direc- tion and measure the deflection from neutral using the control surface as a reference; then measure the deflection from neutral in the oppo- site direction. The sum of the two deflections must not exceed amounts specified below. If the sum of the two deflections exceed amount specified below, replace AN bolts with NAS464 bolts of equivalent diameter and grip length in the push rod and recheck; if unacceptable, replace bearings in'rod end and recheck; if unacceptable, replace trim tab horn bearing and recheck; if still unacceptable, overhaul or replace the trim tab actuator and insure all areas are properly saftied. UP MAXIMUM DEFLECTION (FREKPLAY) (1) Aileron trim tab maximum deflection 0.050 (all airplanes except 336 and 337 series) measured at outboard end of tab. (2) Rudder trim tab maximum deflection 0.070 (310, T310, 320, 340) measured at upper end of tab.