Milestone-Proposal:LORAN: Difference between revisions
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Long lasting near global radio navigation system. Evolved from LORAN, SS-LORAN, LORAN-A, and LORAN-C which was taken out of service recently. | Long lasting near global radio navigation system. Evolved from LORAN, SS-LORAN, LORAN-A, and LORAN-C which was taken out of service recently. | ||
Period of interests: 1940 to 1946 when a new from of radio navigation is proposed, 1941 when R&D work begins, throughout WW2, to 1946 when LORAN is a well established engineered system globally. LORAN's service to just recently is treayed in ..... . | Period of interests: 1940 to 1946 when a new from of radio navigation is proposed, 1941 when R&D work begins, throughout WW2, to 1946 when LORAN is a well established engineered system globally. LORAN's service to just recently is treayed in ..... . | ||
Timeline 1940 to about 1945. why limited . . | Timeline 1940 to about 1945. why limited . | ||
Rad Lab was able to step after loran was running on a firm fundation. | |||
Rad Lab's project involvement terminated when loran was on a solid foundation.. | |||
Jack Pierce's epic article published by the IEEE in 1946 is the prime source for the information here. | Jack Pierce's epic article published by the IEEE in 1946 is the prime source for the information here. | ||
Who was he? | Who was he? | ||
John (Jack) A. Pierce, a senior research fellow at Harvard University, Cambridge, Mass. was awarded the Medal For Engineering Excellence in 1990 for the "design , teaching and advocacy of radio propagation, navigation and timing which led to the development of Loran, Loran C and Omega." In 1941, Pierce began working at the Massachusetts Institute of Technology's Radiation Laboratory which was testing the United States' first hyperbolic radio aid to navigation called Loran. Later work produced Loran C which operated at a lower frequency of 100 kHz. After WWII, he was appointed senior research fellow in applied physics at Harvard and from 1950 to 1974 did work on low frequency navigation aids that lead to Omega. | John (Jack) A. Pierce, a senior research fellow at Harvard University, Cambridge, Mass. was awarded the Medal For Engineering Excellence in 1990 for the "design , teaching and advocacy of radio propagation, navigation and timing which led to the development of Loran, Loran C and Omega." In 1941, Pierce began working at the Massachusetts Institute of Technology's Radiation Laboratory which was testing the United States' first hyperbolic radio aid to navigation called Loran. Later work produced Loran C which operated at a lower frequency of 100 kHz. After WWII, he was appointed senior research fellow in applied physics at Harvard and from 1950 to 1974 did work on low frequency navigation aids that lead to Omega. | ||
Among his many awards are a 1948 Presidential Certificate of Merit and the 1953 Morris Liebmann Prize of the Institute of Radio Engineers. | Among his many awards are a 1948 Presidential Certificate of Merit and the 1953 Morris Liebmann Prize of the Institute of Radio Engineers. | ||
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A second application of the same principle must be used, based on the time difference of a different pair of stations. In practice, one of the stations in the second pair also may be—and frequently is—in the first pair. In simple terms, this means signals must be received from at least three transmitters to pinpoint the receiver's location. By determining the intersection of the two hyperbolic curves identified by this method, a geographic fix can be determined. | A second application of the same principle must be used, based on the time difference of a different pair of stations. In practice, one of the stations in the second pair also may be—and frequently is—in the first pair. In simple terms, this means signals must be received from at least three transmitters to pinpoint the receiver's location. By determining the intersection of the two hyperbolic curves identified by this method, a geographic fix can be determined. | ||
L | L | ||
TODAY LORAN-C was originally developed to provide radionavigation service for U.S. coastal waters & was later expanded to include complete coverage of the continental U.S. as well as most of Alaska. Twenty-four U.S. LORAN-C stations work in partnership with Canadian and Russian stations to provide coverage in Canadian waters and in the Bering Sea. They system provides better than 0.25 nautical mile absolute accuracy for suitably equipped users within the published areas. and provides navigation, location, and timing services for both civil and military air, land and marine users. It is approved as an en route supplemental air navigation system for both Instrument Flight Rule (IFR) and Visual Flight Rule (VFR) operations. The LORAN-C system serves the 48 continental states, their coastal areas, and parts of Alaska. Dedicated Coast Guard men and women have done an excellent job running and maintaining the LORAN-C signal for 52 years. It is a service and mission of which the entire Coast Guard can be proud. | TODAY LORAN-C was originally developed to provide radionavigation service for U.S. coastal waters & was later expanded to include complete coverage of the continental U.S. as well as most of Alaska. Twenty-four U.S. LORAN-C stations work in partnership with Canadian and Russian stations to provide coverage in Canadian waters and in the Bering Sea. They system provides better than 0.25 nautical mile absolute accuracy for suitably equipped users within the published areas. and provides navigation, location, and timing services for both civil and military air, land and marine users. It is approved as an en route supplemental air navigation system for both Instrument Flight Rule (IFR) and Visual Flight Rule (VFR) operations. The LORAN-C system serves the 48 continental states, their coastal areas, and parts of Alaska. Dedicated Coast Guard men and women have done an excellent job running and maintaining the LORAN-C signal for 52 years. It is a service and mission of which the entire Coast Guard can be proud. | ||
Quote from extracted from | Quote from extracted from | ||
Website entitled LORAN A | Website entitled LORAN A | ||
http://www.jproc.ca/hyperbolic/loran_a.html | http://www.jproc.ca/hyperbolic/loran_a.html | ||
" In mid-1942, R. J. Dippy, who had invented the Gee system, was sent to the USA for eight months to assist in Loran development. Many of the techniques used in Gee were adopted, and it was he who insisted that the Loran and Gee receivers were made physically interchangeable so that any RAF or USAAF aircraft fitted for one could use the other by simply swapping units. This was still to prove valuable, long after the war had finished, for Transport Command navigators flying the Australia run from the UK who could plug in the appropriate set depending on where they were. He also designed the ground station timing and synchronization equipment and his assistance speeded up Loran development considerably. Once design had been finalized, production went ahead rapidly. The first Loran-A pair was on the air permanently by June 1942 (Montauk Point, NY, and Fenwick Is, Del.), and by October there were additional stations along the Canadian east coast. The system became operational in early 1943, and late that year stations were established in Greenland, Iceland, the Faeroes and the Hebrides to complete the North Atlantic cover, some being operated by the Royal Navy. At the request of the RAF, another station was put into the Shetlands to cover Norway, and Loran was eventually used by over 450 aircraft of Coastal Command. | " In mid-1942, R. J. Dippy, who had invented the Gee system, was sent to the USA for eight months to assist in Loran development. Many of the techniques used in Gee were adopted, and it was he who insisted that the Loran and Gee receivers were made physically interchangeable so that any RAF or USAAF aircraft fitted for one could use the other by simply swapping units. This was still to prove valuable, long after the war had finished, for Transport Command navigators flying the Australia run from the UK who could plug in the appropriate set depending on where they were. He also designed the ground station timing and synchronization equipment and his assistance speeded up Loran development considerably. Once design had been finalized, production went ahead rapidly. The first Loran-A pair was on the air permanently by June 1942 (Montauk Point, NY, and Fenwick Is, Del.), and by October there were additional stations along the Canadian east coast. The system became operational in early 1943, and late that year stations were established in Greenland, Iceland, the Faeroes and the Hebrides to complete the North Atlantic cover, some being operated by the Royal Navy. At the request of the RAF, another station was put into the Shetlands to cover Norway, and Loran was eventually used by over 450 aircraft of Coastal Command. | ||
" But it was in the Pacific that Loran made its greatest direct contribution to winning the war. Distances in the Pacific Ocean are enormous. As American forces moved westward, air fields were built on many of the small islands and atolls that dot the ocean beyond Hawaii. The limited range of many World War II aircraft demanded that they frequently land and refuel. Navigation by celestial observations is possible only when weather permits and, moreover, it requires a highly trained man who does little on the plane except navigate. Because of the lengthy training required, celestial navigators, particularly on Army Air Corps planes, were extremely scarce. Thus it was that loran provided the easy-to-use, accurate navigational system required to and the air fields so necessary for refueling. | " But it was in the Pacific that Loran made its greatest direct contribution to winning the war. Distances in the Pacific Ocean are enormous. As American forces moved westward, air fields were built on many of the small islands and atolls that dot the ocean beyond Hawaii. The limited range of many World War II aircraft demanded that they frequently land and refuel. Navigation by celestial observations is possible only when weather permits and, moreover, it requires a highly trained man who does little on the plane except navigate. Because of the lengthy training required, celestial navigators, particularly on Army Air Corps planes, were extremely scarce. Thus it was that loran provided the easy-to-use, accurate navigational system required to and the air fields so necessary for refueling. | ||
The intensive bombing of Japan began as soon as air bases could be secured near enough for aircraft to make the round trip. Accurate navigation was necessary not only for precision bombing, but also for carrying a maximum bomb load instead of a large reserve of gasoline. The loran system provided the means for this accurate navigation. By the end of World War II there were 75 standard loran stations serving the needs of aircraft and vessels in operation with over 75,000 receivers in use. Coverage in the Japanese and East China Sea Areas was extended in the 1950's | The intensive bombing of Japan began as soon as air bases could be secured near enough for aircraft to make the round trip. Accurate navigation was necessary not only for precision bombing, but also for carrying a maximum bomb load instead of a large reserve of gasoline. The loran system provided the means for this accurate navigation. By the end of World War II there were 75 standard loran stations serving the needs of aircraft and vessels in operation with over 75,000 receivers in use. Coverage in the Japanese and East China Sea Areas was extended in the 1950's | ||
" The crews of Loran stations varied somewhat in size, depending on their locations. They have averaged about fifteen men. As the stations had to be entirely self-sufficient, they had cooks, hospital corpsmen, damage controlmen, and enginemen, in addition to the electronic technicians who operated and maintained the transmitters. Each station was commanded by a commissioned officer, usually a lieutenant (junior grade ), with a chief petty officer as second in command. Prospective commanding officers were given a short training course in Loran and administration before assignment. Command of a Loran station was almost invariably a young a Coast Guard officer's first independent assignment, and it provided an excellent opportunity for him to demonstrate his leadership qualities. Many young others dreaded Loran duty because of the isolation, but after it is over, nearly all of them felt it had been well worthwhile. At isolated stations, tours of duty were for one year. The great majority of Loran stations were supplied with fuel, bulky spare parts, and large staple items by a Coast Guard supply ship which called once or twice a year. Unless they were located near a large community, Loran stations received mail, personnel, fresh stores, and emergency spare parts by Coast Guard airplane. Most stations had their own airstrip." | " The crews of Loran stations varied somewhat in size, depending on their locations. They have averaged about fifteen men. As the stations had to be entirely self-sufficient, they had cooks, hospital corpsmen, damage controlmen, and enginemen, in addition to the electronic technicians who operated and maintained the transmitters. Each station was commanded by a commissioned officer, usually a lieutenant (junior grade ), with a chief petty officer as second in command. Prospective commanding officers were given a short training course in Loran and administration before assignment. Command of a Loran station was almost invariably a young a Coast Guard officer's first independent assignment, and it provided an excellent opportunity for him to demonstrate his leadership qualities. Many young others dreaded Loran duty because of the isolation, but after it is over, nearly all of them felt it had been well worthwhile. At isolated stations, tours of duty were for one year. The great majority of Loran stations were supplied with fuel, bulky spare parts, and large staple items by a Coast Guard supply ship which called once or twice a year. Unless they were located near a large community, Loran stations received mail, personnel, fresh stores, and emergency spare parts by Coast Guard airplane. Most stations had their own airstrip." | ||
http://www.scribd.com/doc/35814242/MIT-Radiation-Lab-Series-V2-Radar-Aids-to-Navigation | http://www.scribd.com/doc/35814242/MIT-Radiation-Lab-Series-V2-Radar-Aids-to-Navigation | ||
THE COAST GUARD AT WAR | THE COAST GUARD AT WAR | ||
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John (Jack) A. Pierce, who retired from a position as a senior research fellow at Harvard University, Cambridge, Mass. was awarded the Medal For Engineering Excellence in 1990 for the "design , teaching and advocacy of radio propagation, navigation and timing which led to the development of Loran, Loran C and Omega." In 1941, Pierce began working at the Massachusetts Institute of Technology's Radiation Laboratory which was testing the United States' first hyperbolic radio aid to navigation called Loran. It inaugurated in October 1942. Later work produced Loran C which operated at a lower frequency of 100 kHz. After WWII, he was appointed senior research fellow in applied physics at Harvard and from 1950 to 1974 did work on low frequency navigation aids that lead to Omega. | John (Jack) A. Pierce, who retired from a position as a senior research fellow at Harvard University, Cambridge, Mass. was awarded the Medal For Engineering Excellence in 1990 for the "design , teaching and advocacy of radio propagation, navigation and timing which led to the development of Loran, Loran C and Omega." In 1941, Pierce began working at the Massachusetts Institute of Technology's Radiation Laboratory which was testing the United States' first hyperbolic radio aid to navigation called Loran. It inaugurated in October 1942. Later work produced Loran C which operated at a lower frequency of 100 kHz. After WWII, he was appointed senior research fellow in applied physics at Harvard and from 1950 to 1974 did work on low frequency navigation aids that lead to Omega. | ||
Coast Guard Lt. Cmdr. L.M. Harding|a6=Having to locate loran transmitters (North Atlantic Chain) in remote wilderness areas was a big problem. Getting supplies to isolated stations, crews, | Coast Guard Lt. Cmdr. L.M. Harding|a6=Having to locate loran transmitters (North Atlantic Chain) in remote wilderness areas was a big problem. Getting supplies to isolated stations, crews, MIT | ||
Cooperation with foreign countries was required to build stations in Labrador, Newfoundland, Greenland and Iceland. | Cooperation with foreign countries was required to build stations in Labrador, Newfoundland, Greenland and Iceland. | ||
As the program matured, the Rad Lab was able to step back and let more capable organizations, such as the USCG, take over site construction and system operations. By 1948, the Rad Lab had completed its mission. | As the program matured, the Rad Lab was able to step back and let more capable organizations, such as the USCG, take over site construction and system operations. By 1948, the Rad Lab had completed its mission. | ||
Revision as of 23:17, 9 December 2010
This Proposal has not been submitted and may only be edited by the original author.
Pierce Loran.pdf
