Continental Airlines Flight 1760
Encyclopedia
On May 11, 1997 Continental Airlines
Flight 1760, inbound from George Bush Intercontinental Airport
landed safely at Naval Air Station Cabaniss Field
in Corpus Christi
, Texas
by mistake. The plane was approaching Corpus Christi International Airport
through low clouds and directed by Air Traffic Control
to use the runway 31 localizer
to guide them to the runway. When the Captain saw a runway ahead of him after leaving the clouds he made his approach and landed on runway 31 at Cabaniss Field 5 nautical miles (9.3 km) to the southeast.
Contributing to this incident was the tower controller at Corpus Christi turning the runway 13 localizer on for a prior arrival. After that aircraft landed it was not disengaged to turn the localizer to runway 31 back on. Both localizers used the same frequency. There are only 40 frequencies that are currently available for them to operate on. In order to efficiently manage the available radio spectrum many runways utilize the same frequency on opposite ends. To prevent the two transmitting arrays from conflicting with each other only one can be turned on at a time. Pilots are able to distinguish them from each other by listening for the callsign transmitted over the frequency in morse code.
The crew in this case failed to identify the localizer, which would have alerted them they were not on the correct localizer. They were in fact flying an unauthorized back course. On a normal approach a left deflection of the instrument needle means the plane should adjust its course to the left to intercept the localizer. With a back course it is now the other way around, a fly left indication means fly right. This error may have led the plane off course enough to place Cabaniss Field in front of them.
Continental Airlines
Continental Airlines was a major American airline now merged with United Airlines. On May 3, 2010, Continental Airlines, Inc. and UAL, Inc. announced a merger via a stock swap, and on October 1, 2010, the merger closed and UAL changed its name to United Continental Holdings, Inc...
Flight 1760, inbound from George Bush Intercontinental Airport
George Bush Intercontinental Airport
George Bush Intercontinental Airport, is a Class B international airport in Houston, Texas, serving the Houston–Sugar Land–Baytown metropolitan area, the sixth-largest metropolitan area in the United States. Located north of Downtown Houston between Interstate 45 and U.S. Highway 59...
landed safely at Naval Air Station Cabaniss Field
Naval Air Station Corpus Christi
Naval Air Station Corpus Christi , also known as Truax Field, is a naval base located six miles southeast of the central business district of Corpus Christi, in Nueces County, Texas, USA.-History:...
in Corpus Christi
Corpus Christi, Texas
Corpus Christi is a coastal city in the South Texas region of the U.S. state of Texas. The county seat of Nueces County, it also extends into Aransas, Kleberg, and San Patricio counties. The MSA population in 2008 was 416,376. The population was 305,215 at the 2010 census making it the...
, Texas
Texas
Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...
by mistake. The plane was approaching Corpus Christi International Airport
Corpus Christi International Airport
Corpus Christi International Airport is a city-owned public-use airport located five nautical miles west of the central business district of Corpus Christi, in Nueces County, Texas, United States.The airport's new six gate, . Hayden W...
through low clouds and directed by Air Traffic Control
Air traffic control
Air traffic control is a service provided by ground-based controllers who direct aircraft on the ground and in the air. The primary purpose of ATC systems worldwide is to separate aircraft to prevent collisions, to organize and expedite the flow of traffic, and to provide information and other...
to use the runway 31 localizer
Localizer
In aviation, a localizer is one of the components of an Instrument Landing System , and it provides runway centerline guidance to aircraft. In some cases, a course projected by localizer is at an angle to the runway . It is then called a Localizer Type Directional Aid...
to guide them to the runway. When the Captain saw a runway ahead of him after leaving the clouds he made his approach and landed on runway 31 at Cabaniss Field 5 nautical miles (9.3 km) to the southeast.
Contributing to this incident was the tower controller at Corpus Christi turning the runway 13 localizer on for a prior arrival. After that aircraft landed it was not disengaged to turn the localizer to runway 31 back on. Both localizers used the same frequency. There are only 40 frequencies that are currently available for them to operate on. In order to efficiently manage the available radio spectrum many runways utilize the same frequency on opposite ends. To prevent the two transmitting arrays from conflicting with each other only one can be turned on at a time. Pilots are able to distinguish them from each other by listening for the callsign transmitted over the frequency in morse code.
The crew in this case failed to identify the localizer, which would have alerted them they were not on the correct localizer. They were in fact flying an unauthorized back course. On a normal approach a left deflection of the instrument needle means the plane should adjust its course to the left to intercept the localizer. With a back course it is now the other way around, a fly left indication means fly right. This error may have led the plane off course enough to place Cabaniss Field in front of them.