Airworthiness Directive · Amendment 39-11911 · Empresa Brasileira de Aeronautica S.A. (EMBRAER) Model EMB-120 Series Airplanes
Empresa Brasileira de Aeronautica S.A. (EMBRAER) Model EMB-120 Series Airplanes
All Model EMB-120 series airplanes, certificated in any category.
Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (d) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.
This amendment supersedes an existing airworthiness directive (AD), applicable to all EMBRAER Model EMB-120 series airplanes, that currently requires a one-time inspection of the movable backstop of the elevator pitch trim command system to ensure that it is installed correctly, and corrective action, if necessary. That AD also requires installation of a guide to maintain the movable backstop in its correct position. This amendment adds a requirement for an additional one-time inspection. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified in this AD are intended to prevent a sudden change in pitch attitude caused by autopilot disconnect, which could result in reduced controllability of the airplane.
To prevent a sudden change in pitch attitude caused by autopilot disconnect, which could result in reduced controllability of the airplane, accomplish the following:
(a) Within 20 flight hours after January 13, 1998 (the effective date of AD 97-26-22, amendment 39-10265), perform a one-time general visual inspection of the movable backstop of the elevator pitch trim command system to ensure that it is installed correctly, in accordance with Part I of the Accomplishment Instructions of EMBRAER Alert Service Bulletin 120-27-A081, Change 01, dated October 9, 1997. If any discrepancy is found, before further flight, accomplish follow-on corrective actions, in accordance with the alert service bulletin.
(b) Within 75 flight hours after January 13, 1998, install a guide for the movable backstop of the elevator pitch trim command system, in accordance with Part II of the Accomplishment Instructions of EMBRAER Alert Service Bulletin 120-27-A081, Change 01, dated October 9, 1997, or EMBRAER Service Bulletin S.B. 120-27-0081, dated September 1, 2000. As of the effective date of this AD, only EMBRAER Service Bulletin S.B. 120-27-0081 may be used for accomplishment of this paragraph.
(c) Within 100 flight hours after the effective date of this AD: Perform a one-time general visual inspection of the movable backstop of the elevator pitch trim command system to verify proper adjustment of the system and correct rigging of the elevator trim tab in accordance with the Accomplishment Instructions of EMBRAER Service Bulletin S.B. 120-27-0081, dated September 1, 2000. If any discrepancy is detected, before further flight, accomplish follow-on corrective actions in accordance with the service bulletin.
Note 2: For the purposes of this AD, a general visual inspection is defined as: “A visual examination of an interior or exterior area, installation, or assembly to detect obvious damage, failure, or irregularity. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight, or drop-light and may require removal or opening of access panels or doors. Stands, ladders, or platforms may be required to gain proximity to the area being checked.”
(d)(1) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Atlanta Aircraft Certification Office (ACO), FAA. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Atlanta ACO.
(2) Alternative methods of compliance, approved previously in accordance with AD 97-26-22, amendment 39-10265, are approved as alternative methods of compliance with this AD.
Note 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Atlanta ACO.
