Transportation Department, Federal Aviation Administration
We propose to adopt a new airworthiness directive (AD) for all Airbus Model A330-200, -200 Freighter, and -300 series airplanes; and Model A340-200, -300, -500, and -600 series airplanes. This proposed AD was prompted by a determination that, due to significant differences among all airspeed sources, the flight controls will revert to alternate law, the autopilot (AP) and the auto-thrust (A/THR) will automatically disconnect, and the flight director (FD) bars will be automatically removed. Then, if two airspeed sources become similar while still erroneous, the flight guidance computers will display the FD bars again, and enable the re-engagement of the AP and A/THR. In some cases, however, the AP orders may be inappropriate, such as possible abrupt pitch command. This proposed AD would require a software standard upgrade (modification or replacement) of the three flight control primary computers (FCPCs). We are proposing this AD to prevent autopilot engagement under unreliable airspeed conditions, which could result in reduced controllability of the airplane.
Document Headings Document headings vary by document type but may contain the following: the agency or agencies that issued and signed a document the number of the CFR title and the number of each part the document amends, proposes to amend, or is directly related to the agency docket number / agency internal file number the RIN which identifies each regulatory action listed in the Unified Agenda of Federal Regulatory and Deregulatory Actions See the Document Drafting Handbook for more details. Department of Transportation Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA-2016-7424; Directorate Identifier 2015-NM-173-AD] RIN 2120-AA64 AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed rulemaking (NPRM). SUMMARY: We propose to adopt a new airworthiness directive (AD) for all Airbus Model A330-200, -200 Freighter, and -300 series airplanes; and Model A340-200, -300, -500, and -600 series airplanes. This proposed AD was prompted by a determination that, due to significant differences among all airspeed sources, the flight controls will revert to alternate law, the autopilot (AP) and the auto-thrust (A/THR) will automatically disconnect, and the flight director (FD) bars will be automatically removed. Then, if two airspeed sources become similar while still erroneous, the flight guidance computers will display the FD bars again, and enable ( printed page 44236) the re-engagement of the AP and A/THR. In some cases, however, the AP orders may be inappropriate, such as possible abrupt pitch command. This proposed AD would require a software standard upgrade (modification or replacement) of the three flight control primary computers (FCPCs). We are proposing this AD to prevent autopilot engagement under unreliable airspeed conditions, which could result in reduced controllability of the airplane. DATES: We must receive comments on this proposed AD by August 22, 2016. ADDRESSES: You may send comments, using the procedures found in 14 …
Other Federal Register documents from the same docket.
Citation: 81 FR 44235
