OMEGA Navigation System

OMEGA was the first truly global radio navigation system for aircraft, operated by the United States in cooperation with six partner nations.

History

OMEGA was originally developed by the United States Navy for military aviation users. It was approved for development in 1968 with only eight transmitters and the ability to achieve a four mile accuracy when fixing a position. Each Omega station transmitted a very low frequency signal which consisted of a pattern of four tones unique to the station that was repeated every ten seconds. Because of this and radionavigation principles, an accurate fix of the receiver's position could be calculated. OMEGA employed hyperbolic radionavigation techniques and the chain operated in the VLF portion of the spectrum between 10 to 14 kHz. Near its end, it evolved into a system used primarily by the civil community. By receiving signals from three stations, an Omega receiver could locate a position to within 4 nautical miles using the principle of phase comparison of signals. [http://www.jproc.ca/hyperbolic/omega.html]

Omega stations used very extensive antennas in order to transmit their extremely low frequencies. They used grounded or insulated guyed masts with umbrella antennas, or wire-spans across fjords. Some Omega antennas were the tallest constructions on the continent where they stood or still stand.

When six of the eight station chain became operational in 1971, day to day operations were managed by the United States Coast Guard in partnership with Argentina, Norway, Liberia, and France. The Japanese and Australian stations became operational several years later. Coast Guard personnel operated two US stations: one in LaMoure, North Dakota and the other in Kaneohe, Hawaii on the island of Oahu.

Due to the success of the Global Positioning System the use of Omega declined during the 1990s, to a point where the cost of operating Omega could no longer be justified. Omega was permanently terminated on September 30, 1997 and all stations ceased operation.

Some of the stations, such as the LaMoure station, are now used for submarine communications.

OMEGA stations

There were nine Omega stations in total:

Bratland Omega Transmitter

Bratland Omega Transmitter (station A -
architect=
main_contractor=US Coast GuardPaynesville Omega Transmitter (station B -
architect=
main_contractor=US Coast Guard

La Moure Omega Transmitter (station D) situated near La Moure, North Dakota, USA at
architect=
main_contractor=US Coast Guard

Chabrier Omega Transmitter (station E ) near Chabrier on Reunion at
architect=
main_contractor=US Coast GuardShushi-Wan Omega Transmitter (station H) situated near Shushi-Wan on Tsushima Island at coord|34.614739|N|129.453644|E) used as antenna a 389 metre tall tubular steel mast insulated against ground. This mast, which was built in 1973 and which was the tallest structure in Japan ( and perhaps the tallest tubular steel mast ever built) was dismantled in 1998 by using a crane. On the site where it stood an approimately 8 metres tall memorial consting of the mast base ( without the insulator) was built and a segment was built up there for display. On the site of the former helix building, there is today a playground.

ee also

* Alpha, the Russian counterpart of the Omega Navigation System, still in use as of 2006.
* LORAN, low frequency terrestrial radio navigation system, still in use.
* CHAYKA, the Russian counterpart of LORAN
* SHORAN
* Oboe (navigation)
* G-H (navigation)
* GEE (navigation)

Bibliography

* Scott, R. E. 1969. "Study and Evaluation of the Omega Navigation System for transoceanic navigation by civil aviation". FAARD-69-39.
* Asche, George P. USCG 1972. Omega system of global navigation. "International Hydrographic Review" 50 (1):87-99.
* Turner, Nicholas. 1973. Omega: a documented analysis. "Australian Journal of International Affairs":291-305.
* Pierce, J.A. 1974. "Omega: Facts, Hopes and Dreams". Cambridge Mass: Harvard Univ Div of Engineering and Applied Physics.
* Wilkes, Owen, Nils Petter Gleditsch, and Ingvar Botnen. 1987." Loran-C and Omega : a study of the military importance of radio navigation aids". Oslo; Oxford ; New York: Norwegian University Press/Oxford University Press. ISBN 8200077039
* Gibbs, Graham. 1997. "Teaming a product and a global market: a Canadian Marconi company success story". Reston, VA: American Institute of Aeronautics and Astronautics. ISBN 1563472252; ISBN 978-1563472251 [A case study of the commercial development of the Omega Navigation System]

External links

* http://www.jproc.ca/hyperbolic/omega.html
* [http://www.qru.de/beacons2.htm LF Utility Stations 10-100 kHz (compiled by ZL4ALI)]
* [http://www.auroralchorus.com/omega.htm Pictures of former OMEGA-Station La Moure]