AD 2022-03-18 Requires Replacing The Push Rod Assembly With A Modified Push Rod Assembly

The FAA is adopting a new airworthiness directive (AD) for certain British Aerospace (Operations) Limited and  British Aerospace Regional Aircraft Model Jetstream Series 200, Jetstream Model 3101, and Jetstream Model 3201 airplanes.

This AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI identifies the unsafe condition as a bent control rod within the gust lock system, which may enable both power levers to be pushed into the flight range with the gust lock lever fully engaged. This AD requires replacing the push rod assembly with a modified push rod assembly. The FAA is issuing this AD to address the unsafe condition on these products. This AD is effective March 21, 2022.

Supplementary Information: The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to certain serial-numbered British Aerospace (Operations) Limited and British Aerospace Regional Aircraft Model Jetstream Series 200, Jetstream Model 3101, and Jetstream Model 3201 airplanes. The NPRM published in the Federal Register on November 12, 2021 (86 FR 62742). The NPRM was prompted by MCAI originated by the Civil Aviation Authority (CAA), which is the aviation authority for the United Kingdom. CAA has issued CAA AD G-2021-0005, dated August 3, 2021 (referred to after this as “the MCAI”), to address an unsafe condition on certain serial-numbered BAE Systems (Operations) Ltd. Model Jetstream Series 3100 and Series 3200 airplanes.

The MCAI states:

• On 8 October 2019, a Jetstream Series 3200 aircraft aborted take-off at a speed of approximately 130 kt and veered off the runway. The investigation into the serious incident concluded the take-off was initiated with an engaged Gust Lock Mechanism, resulting in a temporary loss of aircraft control. Damage was identified in the Gust Lock mechanism, which allowed both power levers to be moved beyond flight idle with the gust locks engaged.
• The serious incident investigation determined that a bent control rod within the gust lock system made it possible to move both power levers simultaneously to the max position, even though the gust locks were still engaged.
• The gust-lock system is designed to lock and prevent damage to the control surfaces when the aircraft is parked during gusting wind conditions. The system contains a mechanical baulk which prevents both power levers from being moved beyond the flight idle position when the gust locks are engaged.
• Three previous occurrences in which a bent control rod enabled both power levers to be moved simultaneously beyond the flight idle position while the gust lock system was engaged have been identified by the Type Certificate Holder. Service Bulletin 27-JM 5350 was first published in 1992 to introduce a stronger control rod.
• This condition, if not prevented, could lead to partial or total loss of aircraft control. To address this potential unsafe condition, this [CAA] AD mandates the installation of a modified push rod assembly.
• BAE Systems operating manuals contain pre-flight checks that are designed to ensure the gust locks are not engaged during take-off.

You may examine the MCAI in the AD docket at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-0961.

In the NPRM, the FAA proposed to require replacing the push rod assembly with a modified push rod assembly. The FAA is issuing this AD to address the unsafe condition on this product.

FMI: www.regulations.gov