Tue, Nov 16, 2021
AD 2021-18-17 Adds A New Requirement To Update The Version Of The FCC OPS If Necessary
The FAA is superseding Airworthiness Directive (AD) 2012-21-08, which applied to certain The Boeing Company Model 737-600, -700, -700C, -800, and -900 series airplanes.
AD 2012-21-08 required inspecting for part numbers of the operational program software (OPS) of the flight control computers (FCCs) and installing and testing an updated version of the FCC OPS. This AD was prompted by reports that during autopilot coupled instrument landing system (ILS) approaches, the airplane did not capture or track the glideslope correctly. This AD retains the requirement to inspect for part numbers of the OPS of the FCCs, and adds a new requirement to update the version of the FCC OPS if necessary. This AD also expands the applicability to include The Boeing Company Model 737-900ER series airplanes. The FAA is issuing this AD to address the unsafe condition on these products. This AD is effective December 20, 2021.
Supplementary Information: The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2012-21-08, Amendment 39-17224 (77 FR 64711, October 23, 2012) (AD 2012-21-08). AD 2012-21-08 applied to certain The Boeing Company Model 737-600, -700, -700C, -800, and -900 series airplanes. The NPRM published in the Federal Register on February 27, 2020 (85 FR 11319). The NPRM was prompted by reports that during autopilot coupled ILS approaches, the airplane did not capture or track the glideslope correctly. In the NPRM, the FAA proposed to continue to require inspecting for part numbers of the OPS of the FCCs, and to add a new requirement to update the version of the FCC OPS if necessary. The NPRM also proposed to expand the applicability to include The Boeing Company Model 737-900ER series airplanes. The FAA is issuing this AD to address the glideslope capture problem, which could allow the airplane to descend below the glideslope beam and result in controlled flight into
terrain on airplanes that do not have the upgraded FCC OPS installed.
More News
Pilot Also Reported That Due To A Fuel Leak, The Auxiliary Fuel Tanks Were Not Used On June 4, 2025, at 13:41 eastern daylight time, a Piper PA-23, N2109P, was substantially damage>[...]
Have A Story That NEEDS To Be Featured On Aero-News? Here’s How To Submit A Story To Our Team Some of the greatest new stories ANN has ever covered have been submitted by our>[...]
From 2023 (YouTube Edition): Reflections on War’s Collective Lessons and Cyclical Nature The exigencies of war ought be colorblind. Inane social-constructs the likes of racis>[...]
Aero Linx: Colorado Pilots Association (CPA) Colorado Pilots Association was incorporated as a Colorado Nonprofit Corporation in 1972. It is a statewide organization with over 700 >[...]
High Speed Taxiway A long radius taxiway designed and provided with lighting or marking to define the path of aircraft, traveling at high speed (up to 60 knots), from the runway ce>[...]
NTSB Prelim: Piper PA-23
See All