Airworthiness Directive · Amendment 39-14784 · Boeing Model 737 Airplanes
Boeing Model 737 Airplanes
This AD applies to all Boeing Model 737-100, -200, -200C, -300, -400, -500, -600, -700, -700C, -800, and -900 series airplanes; certificated in any category.
The FAA is adopting a new airworthiness directive (AD) for all Boeing Model 737 airplanes. This AD requires repetitive measurement of the freeplay of both aileron balance tabs; repetitive lubrication of the aileron balance tab hinge bearings and rod end bearings; and related investigative and corrective actions if necessary. This AD results from reports of freeplay-induced vibration of the aileron balance tab. The potential for vibration of the control surface should be avoided because the point of transition from vibration to divergent flutter is unknown. We are issuing this AD to prevent excessive vibration of the airframe during flight, which could result in loss of control of the airplane.
You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
The term “service bulletin,” as used in this AD, means the Accomplishment Instructions of the following service bulletins, as applicable:
(1) For Boeing Model 737-100, -200, -200C, -300, -400, and -500 series airplanes: Boeing Special Attention Service Bulletin 737-27-1272, dated September 29, 2005.
(2) For Boeing Model 737-600, -700, -700C, -800 and -900 series airplanes: Boeing Special Attention Service Bulletin 737-27-1273, dated September 29, 2005.
Within 24 months after the date of issuance of the original standard airworthiness certificate or the date of issuance of the original export certificate of airworthiness, or 18 months after the effective date of the AD, whichever is later: Measure the freeplay of both aileron control balance tabs. Repeat the measurement thereafter at the applicable interval in paragraph (g)(1) or (g)(2) of this AD. Do all actions required by this paragraph in accordance with the applicable service bulletin.
(1) For Boeing Model 737-100, -200, and -200C series airplanes: At intervals not to exceed 6,000 flight hours or 24 months, whichever occurs first.
(2) For Boeing Model 737-300, -400, -500, -600, -700, -700C, -800 and -900 series airplanes: At intervals not to exceed 8,000 flight hours or 24 months, whichever occurs first.
If any measurement found in paragraph (g) of this AD is outside the acceptable limits specified in the service bulletin: Before further flight, do the applicable related investigative and corrective actions in accordance with the applicable service bulletin.
(i) Within 9 months after the date of issuance of the original standard airworthiness certificate or the date of issuance of the original export certificate of airworthiness, or within 9 months after the effective date of this AD, whichever is later: Lubricate the aileron balance tab components specified in the applicable service bulletin. Repeat the lubrication thereafter at the applicable interval in paragraph (i)(1), (i)(2), or (i)(3) of this AD. Do all actions required by this paragraph in accordance with the applicable service bulletin.
(1) For Boeing Model 737-100, -200, and -200C series airplanes: At intervals not to exceed 3,000 flight hours or 9 months, whichever occurs first.
(2) For Boeing Model 737-300, -400, -500, -600, -700, -700C, -800, and -900 series airplanes, on which BMS 3-33 grease is not already in use prior to the time the lubrication task is being accomplished: At intervals not to exceed 3,000 flight hours or 9 months, whichever occurs first.
(3) For Boeing Model 737-300, -400, -500, -600, -700, -700C, -800, and -900 series airplanes, on which BMS 3-33 grease is already in use prior to the time the lubrication task is being accomplished: At intervals not to exceed 4,000 flight hours or 12 months, whichever occurs first.
If a freeplay measurement required by paragraph (g) of this AD and a lubrication cycle required by paragraph (i) of this AD are due at the same time or will be accomplished during the same maintenance visit, the freeplay measurement and applicable related investigative and corrective actions must be done before the lubrication is accomplished.
