Canada A320 at San Francisco on Jul 7th 2017, lined up with taxiway for landing

Last Update: October 12, 2018 / 17:03:59 GMT/Zulu time

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Photo of Air Canada C-FKCK, Airbus A320 — Air Canada C-FKCK, Airbus A320 (Photo credit: probabilistic / Flickr / License: CC by)

Incident Facts

Date of incident
Jul 7, 2017

Classification
Incident

Airline
Air Canada

Flight number
AC-759

Departure
Toronto, Canada

Destination
San Francisco, United States

Aircraft Registration
C-FKCK

Aircraft Type
Airbus A320

ICAO Type Designator
A320

An Air Canada Airbus A320-200, registration C-FKCK performing flight AC-759 from Toronto,ON (Canada) to San Francisco,CA (USA) with 140 people on board, was on final approach to runway 28R in night conditions being cleared to land at about 23:56L (06:56Z Jul 8th), when a short time after reading back the landing clearance the crew queried tower to confirm they were cleared to land advising they were seeing lights on the runway, tower advised the runway was clear and they were cleared to land indeed. Another voice chimed in calling they were lined up with the taxiway, tower immediately instructed AC-759 to go around as result commenting it looked like they were lined up for taxiway C. The aircraft went around from below 100 feet AGL. Other flight crew taxiing their aircraft on taxiway C commented the A320 was flying straight over them. The A320 positioned for another approach and landed safely about 15 minutes later.

The FAA is investigating the occurrence rated a serious incident. There were four aircraft on taxiway C, which runs parallel to runway 28R to the right of the runway.

On Jul 11th 2017 the Canadian TSB reported the crew of C-FKCK asked ATC to confirm landing clearance as they were seeing lights when the aircraft was 0.6nm before the runway threshold. The controller was coordinating with another facility when a flight crew of another airliner taxiing on taxiway C queried ATC where AC-759 was going and stated it appeared the aircraft was lined up with taxiway C. AC-759 had already overflown taxiway C by about 0.25nm when ATC instructed the aircraft to go around. 4 aircraft were on taxiway C at the time of the occurrence. It is estimated that AC-759 overflew the first two aircraft by 100 feet, the third by about 200 feet and the last by 300 feet. The closest lateral proximity between AC-759 and one of the aircraft on taxiway C was 29 feet. The NTSB is investigating the occurrence.

On Jul 15th 2017 the NTSB reported the aircraft "was cleared to land on runway 28R at San Francisco International Airport (SFO), San Francisco, California, but instead lined up on parallel taxiway C, which had four air carrier airplanes on it awaiting takeoff clearance (a Boeing 787 that was first in line followed by an Airbus A340, another Boeing 787, and a Boeing 737). The flight descended below 100 feet above the ground and initiated a go-around after overflying the first airplane on the taxiway. ... Night visual meteorological conditions prevailed at the time of the incident."

On Aug 2nd 2017 the NTSB released first preliminary updates on the investigation into the occurrence stating, that runway 28L was closed, approach and runway lights were off, a large flashing X was active at the runway threshold. The runway closure had been NOTAMed, ATIS also included the information that runway 28L was closed and its lightings were out of service. Runway 28R and associated approach lights, including 2400 feet approach lightings, runway edge and center line lighting, runway threshold lighting, runway threshold lighting and PAPIs, were set at default intensity. Taxiway C also was set at default lighting including the green taxiway center line lighting and blue edge lighting.

The captain of AC-759 (ATPL, more than 20,000 hours total, 4,797 hours on type in command) was pilot flying, the first officer (ATPL, more than 10,000 hours total, more than 2,300 hours on type) was pilot monitoring.

About 7 minutes prior to the occcurrence all ATC positions at SFO (local control, local control assist, flight data and clearance delivery) were combined at the local control, at the time of the occurrence one controller was in the tower cab (normal staffing for midnight shift is two controllers).

On taxiway C there were four aircraft waiting for departure, first in sequence was UA-1 (B789, N29961) followed by PR-115 (A343, RP-C3441), UA-863 (B789, N13954) and UA-1118 (B739, N62895).

AC-759 had been cleared for the FMS bridge visual approach to runway 28R. FDR data indicate that AC-759 was aligned with the taxiway C 3nm out and maintained runway heading. About 0.7nm before the runway threshold the crew queried tower whether they were cleared to land, they saw lights on the runway. The aircraft flew too far right for the airport's ASDE-X, so that the aircraft was not displayed on the controller's display over a period of 12 seconds. When the aircraft was 0.3nm from the threshold the controller confirmed the aircraft was cleared to land.

UA-1 radioed first "where's this guy going" followed by "he's on the taxiway". The flight crew of PR-115 (second in queue) switched on their landing lights.

The flight crew of AC-759 advanced their thrust levers when they were at 85 feet AGL, the lowest height before the aircraft began to climb was 59 feet AGL about 2.5 seconds after the thrust levers were advanced. The aircraft was already climbing again when the controller issued the go-around instruction.

The NTSB reported that in post flight interviews both pilots of AC-759 reported they were convinced the lighted runway to their left was runway 28L and they were lined up with runway 28R. They did not recall seeing aircraft on taxiway C, however, something did not look right to them.

On May 3rd 2018 the NTSB opened their docket into the investigation and released the airport surveillance video (see below).

On Sep 25th 2018 the NTSB, while holding the board meeting to determine the causes of the serious incident, reported that the crew initiated the go around at 89 feet AGL, after the go around was initiated the aircraft descended to a minimum of 60 feet before climbing again, the minimum distance to one of the aircraft on the taxiway was 13 feet. The first officer (more than 10,000 hours of experience, the captain had more than 20,000 hour of flight experience) had missed to tune the ILS frequency for runway 28R. The crew was in possession of the NOTAM indicating runway 28L was closed, however, this information was buried in the middle of page 9 on a 28 page flight release package and thus was less than optimal, The crew was provided with three pages of NOTAMs and 5 pages of other information within the release package. When the information was needed, it could not be recalled by the flight crew. The visual impressions of runway 28R and taxiway C, while on approach to taxiway C, were clearly different, however, confirmation bias is a strong human factor overriding such visual impressions. The flashing X on runway 28L was not properly recognized, had the crew been able to identify the runway surface it is likely they'd have identified the flashing X correctly, the crew reported in post flight interviews it was all black to the left, the investigators stated therefore it remained unclear whether the crew had seen the flashing X at all. The ASDE-X (ground movement surveillance) was not designed to predict a taxiway landing, the system thus worked as designed and did not issue an alert. A safety recommendation to review ASDE-X with respect to predict taxiway landings, however, the FAA did not perform such actions, the safety recommendations were closed after "unacceptable" response. The lead investigator stated: "The safety issues identified investigation relate to the need for consistent FMS autotuning capability, effective presentation of relevant flight operations information, equipment to alert flight crew when the airplane is not aligned with the runway surface, modification of surface detection equipment to identify potential taxiway landings, more effective signalling the flight crews of the closure of runways when one or more runways are closed at an airport, and revision to deregulations to review flight crew fatigure." The NTSB chairman worked out on the base of an example that the NOTAMs were a "pile of garbage", for example the flight release documents included a NOTAM about taxiway limitations for aircraft with more than 114 feet wingspan, however, the A320 had only 101 feet wingspan, so why was that NOTAM included? The captain (20,000+ hours of experience) had been up for 19 hours since the last rest he had taken, the first officer was up 12 hours since his last rest. The severity of the incident was not recognized initially, only after review by the FAA and assessment the severity, which the NTSB chairman rated a "close call", was recognized. There was only one controller on the tower staffing all frequencies, as such there was frequency congestion with the controller being distracted on other frequencies. The board voted on and accepted the following proposed probable cause: "The NTSB determine the probable cause of this incident was the flight crew's misidentification of taxiway C as intended landing runway that resulted from the crew members' lack of awareness of the parallel runway closure due to their ineffective review of NOTice to AirMen throughout the flight and during the approach briefing. Contributing to the incident were: 1) the flight crew's failure to tune the instrument landing system frequency for backup lateral guidance, expectation bias, fatigue and break downs in crew resource management and 2) Air Canada's ineffective presentation of approach procedure and NOTAM information" (Summary of the meeting concluded)

On Sep 25th 2018 following the board meeting the NTSB released the findings and probable cause (the final report will be released in due time and summarized as usual by the AVH):

Findings

1. None of the following were factors in this incident: (1) flight crew qualifications, which were in accordance with Canadian and US regulations; (2) flight crew medical conditions; (3) airplane mechanical conditions; and (4) airport lighting, which met US regulations.

2. The first officer did not comply with Air Canada’s procedures to tune the instrument landing system (ILS) frequency for the visual approach, and the captain did not comply with company procedures to verify the ILS frequency and identifier for the approach, so the crewmembers could not take advantage of the ILS’ lateral guidance capability to help ensure proper surface alignment.

3. The flight crew’s failure to manually tune the instrument landing system (ILS) frequency for the approach occurred because (1) the Flight Management System Bridge visual approach was the only approach in Air Canada’s Airbus A320 database that required manual tuning of a navigation frequency, so the manual tuning of the ILS frequency was not a usual procedure for the crew, and (2) the instruction on the approach chart to manually tune the ILS frequency was not conspicuous during the crew’s review of the chart.

4. The first officer’s focus on tasks inside the cockpit after the airplane passed the final waypoint reduced his opportunity to effectively monitor the approach and recognize that the airplane was not aligned with the intended landing runway.

4 Title 14 CFR Part 117, “Flight and Duty Limitations and Rest Requirements: Flightcrew Members.” described the window of circadian low as 0200 through 0559 (body clock time zone).

5. The flight crew-initiated, low-altitude go-around over the taxiway prevented a collision between the Air Canada airplane and one or more airplanes on the taxiway.

6. The controller responded appropriately once he became aware of the potential conflict.

7. Errors that the flight crewmembers made, including their false assumption that runway 28L was open, inadequate preparations for the approach, and delayed recognition that the airplane was not lined up with runway 28R, reflected breakdowns in crew resource management and led to minimal safety margins as the airplane overflew taxiway C.

8. The flight crewmembers’ lack of awareness about the runway 28L closure and the crewmembers’ previous experience seeing two parallel runways at San Francisco International Airport led to their expectation to identify two runway surfaces during the approach and resulted in their incorrect identification of taxiway C instead of runway 28R as the intended landing runway.

9. Although the notice to airmen about the runway 28L closure appeared in the flight release and the aircraft communication addressing and reporting system message that were provided to the flight crew, the presentation of the information did not effectively convey the importance of the runway closure information and promote flight crew review and retention.

10. The cues available to the flight crewmembers to indicate that the airplane was aligned with a taxiway were not sufficient to overcome their belief, as a result of expectation bias, that the taxiway was the intended landing runway.

11. Multiple salient cues of the surface misalignment were present as the airplane approached the airport seawall, and one or more of these cues likely triggered the captain’s initiation of a go-around, which reportedly occurred simultaneously with the first officer’s call for a go-around.

12. The captain and the first officer were fatigued during the incident flight due to the number of hours that they had been continuously awake and circadian disruption, which likely contributed to the crewmembers’ misidentification of the intended landing surface, their ongoing expectation bias, and their delayed decision to go around.

13. Current Canadian regulations do not, in some circumstances, allow for sufficient rest for reserve pilots, which can result in these pilots flying in a fatigued state during their window of circadian low.

14. Flight safety would be enhanced if airplanes landing at primary airports within class B and class C airspace were equipped with a cockpit system that provided flight crews with positional awareness information that is independent of, and dissimilar from, the current instrument landing system backup capability for navigating to a runway.

15. Although the investigation into this incident identified significant safety issues, cockpit voice recorder information, had it been available, could have provided direct evidence regarding the flight crew’s approach preparation, cockpit coordination, perception of the airport environment, and decision-making.

16. Once the flight crewmembers perceived lights on the runway, they decided to contact the controller to ask about the lights; however, their query was delayed because of congestion on the tower frequency, which reduced the time available for the crewmembers to reconcile their confusion about the lights with the controller’s confirmation that the runway was clear.

17. Although the use of line up and wait (LUAW) procedures during single-person air traffic control operations was not a factor in this incident, the tower controllers should have delayed consolidating local and non-local control positions until LUAW procedures were no longer needed.

18. If an airplane were to align with a taxiway, an automated airport surface detection equipment alert would assist controllers in identifying and preventing a potential taxiway landing as well as a potential collision with aircraft, vehicles, or objects that are positioned along taxiways.

19. Increased conspicuity of runway closure markers, especially those used in parallel runway configurations, could help prevent runway misidentification by flight crews while on approach to an airport.

Probable Cause

The NTSB determines that the probable cause of this incident was the flight crew’s misidentification of taxiway C as the intended landing runway, which resulted from the crewmembers’ lack of awareness of the parallel runway closure due to their ineffective review of NOTAM information before the flight and during the approach briefing.

Contributing to the incident were (1) the flight crew’s failure to tune the ILS frequency for backup lateral guidance, expectation bias, fatigue due to circadian disruption and length of continued wakefulness, and breakdowns in CRM and (2) Air Canada’s ineffective presentation of approach procedure and NOTAM information.

Following safety recommendations were released:

To the Federal Aviation Administration:

1. Work with air carriers conducting operations under Title 14 Code of Federal Regulations Part 121 to (1) assess all charted visual approaches with a required backup frequency to determine the flight management system autotuning capability within an air carrier’s fleet, (2) identify those approaches that require an unusual or abnormal manual frequency input, and (3) either develop an autotune solution or ensure that the manual tune entry has sufficient salience on approach charts.

2. Establish a group of human factors experts to review existing methods for presenting flight operations information to pilots, including flight releases and general aviation flight planning services (preflight) and aircraft communication addressing and reporting system messages and other in-flight information; create and publish guidance on best practices to organize, prioritize, and present this information in a manner that optimizes pilot review and retention of relevant information; and work with air carriers and service providers to implement solutions that are aligned with the guidance.

3. Establish a requirement for airplanes landing at primary airports within class B and class C airspace to be equipped with a system that alerts pilots when an airplane is not aligned with a runway surface.

4. Collaborate with aircraft and avionics manufacturers and software developers to develop the technology for a cockpit system that provides an alert to pilots when an airplane is not aligned with the intended runway surface and, once such technology is available, establish a requirement for the technology to be installed on airplanes landing at primary airports within class B and class C airspace.

5. Modify airport surface detection equipment (ASDE) systems (ASDE-3, ASDE-X, and airport surface surveillance capability) at those locations where the system could detect potential taxiway landings and provide alerts to air traffic controllers about potential collision risks.

6. Conduct human factors research to determine how to make a closed runway more conspicuous to pilots when at least one parallel runway remains in use, and implement a method to more effectively signal a runway closure to pilots during ground and flight operations at night.

To Transport Canada:

7. Revise current regulations to address the potential for fatigue for pilots on reserve duty who are called to operate evening flights that would extend into the pilots’ window of circadian low.

On Oct 12th 2018 the NTSB released their final report.