EASA SIB AIR-20-19
Boeing 777 and 787 Aeroplanes - Flight Management Computing Software System
Summary
The Special Airworthiness Information Bulletin SAIB: AIR-20-19 is an FAA information bulletin addressing a flight management computing software anomaly affecting Boeing 777 and 787-8, -9, and -10 airplanes. The bulletin informs operators about an issue where the auto-throttle may fail to disconnect during a balked landing, potentially causing airspeed reduction and stick shaker activation. It provides background on the software versions involved and references Boeing Flight Crew Operations Manual Bulletins for guidance.
What Changed
This bulletin introduces awareness of an auto-throttle software anomaly in the Boeing 777 AIMS V17B software and the Boeing 787 Flight Management Block Point 4 software that can cause the auto-throttle to remain engaged in IDLE mode during a balked landing. It highlights Boeing's ongoing development of a software update to correct this issue and the FAA's consideration of rulemaking to mandate installation once available.
Why It Matters
This issue is critical for aviation professionals because the auto-throttle remaining engaged in IDLE mode during a balked landing can lead to unintended airspeed reduction and activation of the stick shaker, increasing the risk during go-around maneuvers. Operators and flight crews need to understand and mitigate this risk to maintain safe flight operations and comply with recommended procedures. Maintenance and compliance teams must prepare for upcoming software updates and potential regulatory mandates.
What To Do
Owners and operators of affected Boeing 777 and 787 airplanes should promptly incorporate the procedures outlined in the Boeing Flight Crew Operations Manual Bulletins TBC-108 and TBC-158 to manage the auto-throttle anomaly during balked landings. They should monitor Boeing and FAA communications for the release and mandatory installation of the corrective software update. No specific compliance deadline is provided, but early adoption of recommended procedures is advised.