Feb 27, 2018 - [We were] being vectored for the ILS runway 07R approach at Anchorage, AK. Visual. Meteorological Conditi
2/27/2018
FOR YOUR INFORMATION
2018-44/6-3 1492590
To:
FAA (ATM ANC Tower)
Info:
FAA (AVP-1, AVP-200, AFS-200, AFS-400, AFS-430, AFS-280, ANM-100, ATM A11 TRACON, AQS-230, Director of Air Traffic Operations WSA North), A4A, ALPA, AOPA, APA, ASAP, ATSAP, ATSG, CAPA, IATA, ICAO, ICASS, IFALPA, IPA, NATCA, NBAA, NTSB, RAA, Airport Manager, Stevens Anchorage International Airport (ANC), AK
From: Linda J. Connell, Director
NASA Aviation Safety Reporting System Re:
ANC Localizer 07R Reliability
We recently received an ASRS report describing a safety concern that may involve your area of operational responsibility. We do not have sufficient details to assess either the factual accuracy or possible gravity of the report. It is our policy to relay the reported information to the appropriate authority for evaluation and any necessary follow-up. We feel you should be aware of the enclosed deidentified report.
To properly assess the usefulness of our alert message service, we would appreciate it if you would take the time to give us your feedback on the value of the information that we have provided. Please contact Dennis Doyle at (408) 541-2831 or email at
[email protected]
Aviation Safety Reporting System P.O. Box 189 | Moffett Field, CA | 94035-0189
ACN: 1492590 Time Date: 201710 Local Time Of Day: 1801-2400 Place Locale Reference.Airport: ANC.Airport State Reference: AK Environment Flight Conditions: VMC Aircraft 1 ATC / Advisory.TRACON: A11 Make Model Name: B747 Undifferentiated or Other Model Person 1 Function.Flight Crew: Pilot Flying Function.Flight Crew: First Officer ASRS Report Number: 1492590 Events Anomaly.ATC Issue: All Types Anomaly.Deviation - Track / Heading: All Types Detector.Person: Flight Crew Result.General: None Reported / Taken Narrative 1 [We were] being vectored for the ILS runway 07R approach at Anchorage, AK. Visual Meteorological Conditions were present at the time. Flight was controlled using the Center Autopilot. Airplane mechanical deferred items included the Left Autopilot as inoperative. At about ten (10) miles west of the airport and intercepting the localizer to runway 07R, the plane captured the course and continued. However, the localizer course failed to lock. The plane drifted off course and required correcting using the Heading Select commands. Small corrections were made and the localizer approach was re-armed. A few moments later the localizer was captured. The Flight Management Annunciators displayed LOC, thus affirming course capture. The approach continued to the final segment, located about five miles from the runway. However, there was a second correction that was required. The autopilot was disconnected at about 1.6 miles and 500 feet AGL, the approach continued to an uneventful landing. This is the second occurrence in the past month of an irregularity with the ILS localizer runway 07R at Anchorage. The localizer fails to lock after course capture. An aside, a conversation was made with another air carrier operator. They affirmed a question about the localizer locking course during approach to runway 07R. [Suggest] careful monitoring of Flight Management Annunciators during an ILS runway 07R approach at Anchorage is standard operating procedure. An approach into instrument
meteorological conditions and localizer lock failure would require prompt intervention, including considering a manually flown approach. Synopsis B747 First Officer reported a course deviation resulted when the ANC 07R localizer signal displayed anomalies. Reporter stated he has seen this issue in the past.
