Flight Control System

1 FAA Aviation Safety SPECIAL AIRWORTHINESS INFORMATION BULLETIN SUBJ: Flight Control System SAIB: NM-17-09 Date: March 9, 2017 This is information only. Recommendations aren’t mandatory.

Introduction

This Special Airworthiness Information Bulletin (SAIB) advises owners and operators of The Boeing Company Model 767-200, -300, -300F, and -400ER series airplanes of inspection and maintenance procedural changes for certain inboard spoiler power control actuators (PCAs) of the flight control system.

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

Background

An operator of a Model 767 airplane reported the loss of two hydraulic systems when the speedbrakes were deployed during landing. This incident occurred during a non-revenue flight following a periodic maintenance check. It was determined that two inboard spoiler PCAs were leaking hydraulic fluid, which could have been caused by incorrect usage of certain tooling during maintenance. If hydraulic pressure is applied while lock collars are installed on the inboard spoiler PCAs, damage to the PCAs can occur, resulting in the loss of hydraulic fluid during operation. This only affects inboard spoiler PCAs (installed on spoilers 5 through 8) manufactured by one supplier and used on Model 767 airplanes having line numbers 1 through 1108 inclusive.

Boeing has issued Alert Service Bulletin 767-27A0236, dated November 9, 2016, to address this concern. The service information provides instructions to inspect the inboard spoiler PCAs on affected Model 767 airplanes in order to prevent the loss of hydraulic fluid. Procedural changes have also been made to the Boeing 767 Aircraft Maintenance Manual (AMM), Section 27-61-00, dated December 22, 2016. The revised AMM procedures provide additional instructions to inspect the inboard spoiler PCAs for damage and leakage anytime the lock collars are used.

Recommendations

The FAA recommends that owners and operators of the affected airplanes incorporate the procedures outlined in the referenced service information.

For Further Information Contact

Kelly McGuckin, Aerospace Engineer, Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue SW., Renton, Washington 98057-3356; telephone 425-917-6490; fax 425-917-6590; e-mail [email protected].

2 For Related Service Information Contact:

Boeing Commercial Airplanes, Attention: Contractual & Data Services (C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740; telephone 562-797-1717; Internet https://www.myboeingfleet.com.