Wednesday, January 15, 2014

How to land at the wrong airport

Twice in recent memory a large jet airliner has landed at the wrong airport. The Kansas City Star reported on January 14 that a Southwest Airlines 747 landed at the M. Graham Clark Taney County airport in Hollister, Mo. instead of the larger airport in Branson. Several months earlier, in November 2013, a Boeing 747 freighter operated by the Boeing Company itself, accidentally landed at Wichita’s Col. James Jabara airport instead of McConnell Air Force Base.

The Dallas News reports that the Southwest jet landed at Hollister at 3:40 p.m. Archived weather reports on show that the weather was partly cloudy with the clouds at about 5,000 feet. Similarly, in the case of the Boeing in Wichita, the preliminary NTSB report notes that “visual meteorological conditions prevailed,” meaning that cloud ceilings were at least 1,000 feet and visibility was at least three miles. The 747 landed at 9:20 p.m.

The two recent episodes were not the first airliners to land at the wrong field. In one famous incident in 1967, a TWA pilot mistakenly landed his Boeing 707 at the Ohio State University airport instead of the intended Port Columbus. The story is recounted in the Columbus Dispatch.

Paradoxically, it can be easier to locate an airport when the weather is bad than when it is good. In cloudy weather, instrument approaches lead the airplane directly to the landing runway with great precision. When the weather is good, air traffic control vectors the pilot toward the airport, but often the aircraft is cleared for a visual approach. According to the Pilot Controller Glossary, to accept a visual approach, the pilot must have “either the airport or the preceding aircraft in sight.”

In many cases, landing at the wrong airport is a case of mistaken identity. The pilot sees an airport and misidentifies it as his destination. This can be easy to do because urban areas often have many airports. Since runways are usually aligned with the prevailing winds, many airports in the same area can have a similar configuration.

In Missouri,’s airport database shows that Clark airport (KPLK) has runways numbered 12 and 30, consistent with the magnetic courses of 120 and 300 degrees. Branson (KBBG) is similarly configured with runways 14 and 32. A telltale difference is that Branson’s runway is 7,140 feet long where Clark is only 3,738 feet. McConnell AFB (KIAB) has paired runways that are numbered 1 and 19 left and right. These runways are each 12,000 feet long. The smaller Jabara airport (KAAO) has a 6,101 foot runway numbered 18 and 36.

The airport pairs are also close together. Jabara is eight miles from McConnell. Clark is only six miles from Branson.

It is likely that the pilots were cleared for a visual approach and simply mistook the smaller airports for their larger neighbors due to the similar runway configurations and proximity.

The problem could have been exacerbated for the Boeing 747 pilots because their approach took place at night. There are numerous potential pitfalls with night landings, including the difficulty in picking urban airport lights out from the surrounding city lights. Often brighter city lights can make airports nearly impossible to spot. In addition, night landings are subject to a number of visual illusions that could have made it difficult for the crew to detect the short length of the Jabara airport.

To avoid making this sort of mistake, pilots should verify the runway before they land. This can be done by using the same instrument systems that help the airplane find the runway in bad weather. A good procedure is to tune in the instrument landing system (ILS) frequency for the runway that is being used. If the needles don’t center on short final, the airplane is not approaching the right runway.

For runways without an ILS, most modern jets are equipped with GPS. Over the past few years, many smaller airports have added RNAV/GPS approaches. These can also be used as a backup. If the runway does not have a GPS approach, the pilot can still select the runway waypoint and create his own visual approach with a user waypoint about three miles in front of the landing runway.

Landing at the wrong airport is not a common mistake, but it is a serious one. The pilots in question may lose their licenses and find their careers at a premature end. Using navigation systems as a backup on a visual approach can prevent an embarrassing and potentially career-ending error.

Originally published on Aviation Examiner

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