Oops, We Messed Up

With a flight management computer, navigational displays, and a head-up display (HUD), one would think that it would be virtually impossible for competent pilots to land their airliner at the wrong airport.

Yet it happens.

Little chinks in the defenses against such embarrassment exist. Evidence comes from the night time mistaken landing of Southwest Airlines Flight 4013, a B737 with 124 passengers, at M. Graham Clark Downtown Airport, which was a scant six miles distant from the intended destination at Branson Airport, MO.

Seen in daylight, the two airports are close to one another

Seen in daylight, the two airports are close to one another

More than a year and a half after this 12 January 2014 mix-up, the National Transportation Safety Board (NTSB) has still not published its investigation report. However, the Board has released a slew of pertinent documents. One 37-page paper contains summaries of investigators’ interviews with the flight crew, Southwest check airmen, and an aircrew program manager from the Federal Aviation Administration (FAA).

Pertinent extracts will set up the discussion to follow.

▪ First, the post-incident interview with Captain Ronald Horne.

For the planned approach and landing at Branson Airport (3-digit code BBG), he was the pilot monitoring (PM) while the first officer had the pilot flying (PF) duties. Horne said he checked the central display unit in the cockpit to double check the flight legs prior to departure from Chicago’s Midway field. At that time, he recalled that the approach to Branson was not entered in the display.

As they neared their destination, they were cleared to land by Branson’s tower controller.

The first officer, Kenneth Langford, did a pre-landing brief, a visual approach to Branson’s Runway 14. Horne then placed 5- and 10-mile rings around Runway 14 on the displays.

The tower controller at Branson asked if they had the airport in sight. Yes, Horne radioed; both pilots saw a beacon out ahead of them, which they assumed to be Branson Airport. Flight 4013 was cleared for a visual approach.

Captain Horne recalled that the runway ahead of them was “lit up like an operational airfield”. It was a clear, dark night and the runway appeared very bright (like the fabled Sirens who lured sailors to crash their ships on the rocks).

Horne said he was concentrating on the head-up display to make sure the touchdown zone and the runway length at Branson were dialed in, and that the airplane maintained the requisite 3-degree glide slope.

Horne said he was focused on airspeed. After they touched down, the end of the runway seemed very close (Branson’s Runway 14 was 7,100 feet long; the Downtown Airport’s Runway 12 was 3,700 feet long). Maximum braking was applied, at which point Captain Horne figured “something was terribly wrong”.

After the airplane came to a safe stop, the passengers debarked for busses called to take them to Branson Airport.

The curious at Downtown Airport gape at the Southwest airliner that mistakenly landed there

The curious at Downtown Airport gape at the Southwest airliner
that mistakenly landed there

Horne said the head-up display may have contributed to being more focused on having a stabilized glide path to the runway, to the exclusion of other information in the cockpit — which would have indicated they were about to land at the wrong airport. The fact that he had never flown before to Branson Airport, while the first officer had done so, gave Horne “comfort” that all was well.

▪ Investigators’ interview with First Officer Kenneth Langford, the pilot flying.

He recalled entering Branson in the flight management computer. He said he briefed the visual approach to Branson’s Runway 14. Downtown Airport was mis-identified as Branson because it was the first set of lights they saw and it had a similar runway alignment (Downtown Airport’s Runway 12, i.e., 120 degrees alignment and very close to Branson’s Runway 14, with an azimuth of 140 degrees).

There were no centerline lights, just runway lights. Branson did not have centerline lights either, and no other airports were seen in the area.

It occurred to him that no PAPI lights were showing. These lights, located alongside the runway, indicate to the pilot where he is high, low, or on the glide slope to touchdown. PAPI is an acronym for Precision Approach Path Indicator.

Langford noticed the absence of PAPI lights, but at this point the aircraft was just 500 feet above the ground. He did not notice the number 12 painted on the runway.

When cleared to Branson by air traffic control, he had set the Branson approach on the flight management computer but when cleared for the visual approach he turned away for a 5-mile final approach; once he turned away, they were basically flying visually and not using any backup instrumentation.

▪ Interview with Daniel Menius, a Southwest dispatcher, occupying the cockpit jump seat to log required observation time.

Before the flight departed from Midway, the captain said he had never been to Branson and the first officer said he had been there only once (the first officer did not specify if he had been the pilot flying or if it had been a night flight). Dispatcher Menius said the first officer claimed he was going to be the “expert” as neither Captain Horne nor dispatcher Menius had ever been to Branson before.

Menius thought Branson air traffic control asked if the pilots had the airport in sight. The pilots said they saw the beacon, but not the runway lights. This transmission stuck out to Menius.

He thought he saw an airport in the distance, but the airplane quickly made a left turn and the runway was right in front of them. At the time he thought, “Oh, I was off, that must be Northwest Arkansas Regional over there.” He dismissed the notion that the one in the distance was where they were heading.

It piqued his interest that there was no ramp lighting whatsoever. If Flight 4013 was expected to arrive, the ramp area would have been lit up.

He did not verbalize these thoughts, as they were below 10,000 feet and the sterile cockpit rule applied.

He recalled that the runway edge lights were lit, but that was all. There were no center line lights on the runway.

When they were crossing the runway threshold, he recalled seeing the number 12 on the runway and thought, “Is this happening? This is a dream; this is not right.”

He thought, “Oh my God, this is not the right airport.” He knew for a fact that [runway] 14 was the one they were supposed to be landing on. He thought it was a dream.

It never occurred to him that the runway could be too short and that a potentially catastrophic rollout was occurring.

The crew did not discuss afterward what went wrong. They seemed a little in shock.

▪ Interview with Jerry Griewahn, FAA aircrew program manager for the B737.

He said that visual approaches at Southwest were required to be backed up by a navigational aid they had available in the cockpit. This event was all related to human factors; they crew had developed tunnel vision and “it was all downhill from there.” Both pilots saw the Downtown Airport lights and “that caught their attention and distracted them and they never went back in” the cockpit (to check their instrument displays).

▪ Interview with Denny Keller, Southwest Airlines check airman.

He did not know why runway and approach lighting were not required to be briefed for visual approaches. Some pilots would include that information and some would not.

When asked how pilots were trained to land at the correct airport, he said they were trained to use all available resources, to back up visual approaches and, when they were close in, to ensure that the runway numbers and the heading for the runway were correct.

He said the presence of a VASI [visual approach slope indicator] or a PAPI could be part of a visual approach briefing, but it was not a requirement.

▪ Interview with Craig Henrichson, Southwest Airlines check airman:

Visual approaches were required to be backed up by an instrument approach. Runway and approach lighting, he said, were not required to be part of a visual approach briefing. When asked why not, he responded, “Ask the guy who wrote it.” The lighting was also not required to be briefed on a visual approach at night.

He said that there have been no changes to procedures since the incident. A flyer was distributed to Southwest pilots re-emphasizing that visual approaches were to be backed up by instrument approaches.

Well, the two check airmen may be surprised when the NTSB’s final report is issued; there is a high probability that it will recommend some procedural changes. For example, having an instrument landing programmed into the computer as a backup to the visual landing approach is only useful if the pilots look at their navigation display on the instrument panel. It is evident that neither Captain Horne nor First Officer Langford looked at the display on the panel in front of them. The absence of a requirement to brief before landing the runway lighting at an airport for a night visual approach is almost sure to produce a corrective recommendation from the NTSB. For a visual approach at night, lighting is an essential aid.

Crew resource management seems poor. The captain was depending on the first officer; Captain Horne was fiddling with the head up display, which did not provide an identification of the airport where they were supposed to be landing. Even though the dispatcher in the jump seat was not formally part of the flight crew, he was a Southwest employee. On something related to possibly landing at the wrong airport — definitely within the bounds of permitted “sterile” conversation — he should have spoken up.

The captain’s leadership seems deficient. He failed to correctly identify the airport and to confirm that it conformed to the destination programmed into the cockpit navigation display. He did not notice the different (albeit close) runway heading, the shortness of the runway, and other cues that they were about to commit a big mistake. Above all, he never should have deferred completely to the first officer, who had not landed at Branson before at night. In short, the captain evidenced no leadership.

After the incident, the first officer retired from Southwest. The captain resumed flying after receiving additional training. The nature of that training is unknown, but the essential failure is one of leadership, not technical expertise.