Milestone-Proposal:LORAN: Difference between revisions
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Standard Loran is a hyperbolic system that was developed primarily for navigation over water. It operate on one of several frequencies between1700and 2000 kc/seeand thereforeenjoyspropaga- tion characteristics determined primarily by soil conductivity and ionospheric conditions. Transmitters now in use radiate about 100kw and give a ground-wave range oversea water of about 700 nautical miles in the daytime. The day timer ange over land is seldom more than 250 miles even for high-flying aircraft and is scarcely100miles at the surface of the earth. At nightthe ground-wave range oversea water is reduced to about 500 miles by the increase in atmospheric noise, but sky waves, which are almost completely absorbed by day,become effective and increase the reliable night range to about 1400miles. | Standard Loran is a hyperbolic system that was developed primarily for navigation over water. It operate on one of several frequencies between1700and 2000 kc/seeand thereforeenjoyspropaga- tion characteristics determined primarily by soil conductivity and ionospheric conditions. Transmitters now in use radiate about 100kw and give a ground-wave range oversea water of about 700 nautical miles in the daytime. The day timer ange over land is seldom more than 250 miles even for high-flying aircraft and is scarcely100miles at the surface of the earth. At nightthe ground-wave range oversea water is reduced to about 500 miles by the increase in atmospheric noise, but sky waves, which are almost completely absorbed by day,become effective and increase the reliable night range to about 1400miles. | ||
HISTORY - USE POINT TO USCG | HISTORY - USE POINT TO USCG | ||
The following paragraphs tell the story of Loran's beginning, its first leaders, location where the work was performed, the installation of the first | The following paragraphs tell the story of Loran's beginning, its first leaders, location where the work was performed, the installation of the first | ||
Engineering is not a solo activity. When a grande long-lived engineered system like LORAN, .. this nomination milestone gives credit to those persons that worked on the so-called Project 3 or C of the Radiation Laboratory of MIT during 1941 to c1946. This group of individuals did not work in the Rad Lab building, having nothing to do with microwave or radar. These individuals work in the Hood Building and other building in Boston and Cambridge. The USCG had a permanent office working on this project. One person in particular that deserves mention is Coast Guard Lt. Cmdr. L.M. Harding who provided supervision and direction for the Pacific Loran ... | Engineering is not a solo activity. When a grande long-lived engineered system like LORAN, .. this nomination milestone gives credit to those persons that worked on the so-called Project 3 or C of the Radiation Laboratory of MIT during 1941 to c1946. This group of individuals did not work in the Rad Lab building, having nothing to do with microwave or radar. These individuals work in the Hood Building and other building in Boston and Cambridge. The USCG had a permanent office working on this project. One person in particular that deserves mention is Coast Guard Lt. Cmdr. L.M. Harding who provided supervision and direction for the Pacific Loran ... | ||
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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 . . | ||
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, 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. | ||
Among his many awards are a 1948 Presidential Certificate of Merit and the 1953 Morris Liebmann Prize of the Institute of Radio Engineers. He earned a BA in physics from Harvard while an assistant at the University's Cruft Laboratory. (Photo and copy courtesy IEEE Spectrum, August 1990) | Among his many awards are a 1948 Presidential Certificate of Merit and the 1953 Morris Liebmann Prize of the Institute of Radio Engineers. He earned a BA in physics from Harvard while an assistant at the University's Cruft Laboratory. (Photo and copy courtesy IEEE Spectrum, August 1990) | ||
JA Pierce was . . .???///// | |||
In the spring of 1941, a small technical group was formed to receive and test some radio navigation equipment already being fabricated. This group, headed by Melville Eastman of the Microwave Committee, founder of General Radio Corporation of Cambridge, was organized under the newly formed Radiation Laboratory of the Massachusetts Institute of Technology, from which it drew two or three key personnel, while other were recruited from outside sources. Further research and investigations were undertaken and soon indicated that changes in the basic design were necessary.. | In the spring of 1941, a small technical group was formed to receive and test some radio navigation equipment already being fabricated. This group, headed by Melville Eastman of the Microwave Committee, founder of General Radio Corporation of Cambridge, was organized under the newly formed Radiation Laboratory of the Massachusetts Institute of Technology, from which it drew two or three key personnel, while other were recruited from outside sources. Further research and investigations were undertaken and soon indicated that changes in the basic design were necessary.. | ||
radio frequency, patterns, wave reflection | radio frequency, patterns, wave reflection | ||
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Refer to Pierce article | Refer to Pierce article | ||
INSERT IMAGE HERE showing the extent of coverage in 5 years of effort... 1946 | INSERT IMAGE HERE showing the extent of coverage in 5 years of effort... 1946 | ||
LORAN first signal began transmissions during the summer 1941. New LORAN transmitting stations were added around the Atlantic coast throughout WW2 and the continental United States. The LORAN-C system became obsolete, replaced by GPS navigation system and the LORAN system was terminated in a special ceremony orchestrated by USGC Washington headquarters in 8 February 2010.theHow the LORAN project was initiated, organized and managed is very interested, if not note worthy. | LORAN first signal began transmissions during the summer 1941. New LORAN transmitting stations were added around the Atlantic coast throughout WW2 and the continental United States. The LORAN-C system became obsolete, replaced by GPS navigation system and the LORAN system was terminated in a special ceremony orchestrated by USGC Washington headquarters in 8 February 2010.theHow the LORAN project was initiated, organized and managed is very interested, if not note worthy. | ||
Rapid construction under extreme weather conditions. System operation by operators from different nations: US, Canada and Denmark. Collaborative effort. MIT Lab was initially responsible for the entire program, but under close hands-on direction of the USCG. USGC's role increased. | Rapid construction under extreme weather conditions. System operation by operators from different nations: US, Canada and Denmark. Collaborative effort. MIT Lab was initially responsible for the entire program, but under close hands-on direction of the USCG. USGC's role increased. | ||
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LORAN Principle use | LORAN Principle use | ||
BOSDWITCH pdf | BOSDWITCH pdf | ||
Principle | Principle | ||
A crude diagram of the LORAN principle - the difference between the time of reception of synchronized signals from radio stations A and B is constant along each hyperbolic curve; when demarcated on a map, such curves are known as "TD lines" | A crude diagram of the LORAN principle - the difference between the time of reception of synchronized signals from radio stations A and B is constant along each hyperbolic curve; when demarcated on a map, such curves are known as "TD lines" | ||
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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. | 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. | ||
LORAN-C Termination Information | LORAN-C Termination Information | ||
REFERENCES | REFERENCES | ||
JA Pierce, "An Introduction to Loran", IEEE AES Magazine 1990 (attached) | JA Pierce, "An Introduction to Loran", IEEE AES Magazine 1990 (attached) | ||
Bowditch, American Practical Navigator.U.S. Navy Hydrographic Office, 1958 pp. 333 - 343 | Bowditch, American Practical Navigator.U.S. Navy Hydrographic Office, 1958 pp. 333 - 343 | ||
Willoughy, Malcom Francis; The Story of LORAN in the U.S. Coast Guard in World War II, Arno Pro, 1980 | Willoughy, Malcom Francis; The Story of LORAN in the U.S. Coast Guard in World War II, Arno Pro, 1980 | ||
http://www.uscg.mil/History/STATIONS/LORAN_Section_1.asp | http://www.uscg.mil/History/STATIONS/LORAN_Section_1.asp | ||
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 | ||
WEBSITES | WEBSITES | ||
http://www.loran-history.info/ | http://www.loran-history.info/ | ||
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http://www.uscg.mil/History/STATIONS/LORAN_Section_1.asp | http://www.uscg.mil/History/STATIONS/LORAN_Section_1.asp | ||
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 | ||
TO PROBE FURTHER | TO PROBE FURTHER | ||
I. B.W. Sittelry, “ELEMENTS OFLORAN,” MIT Radiation Laboratoyr Re- port No. 499; March, 1944; also available as Navships 900, 027, Bureau of Ships, April 1944 | I. B.W. Sittelry, “ELEMENTS OFLORAN,” MIT Radiation Laboratoyr Re- port No. 499; March, 1944; also available as Navships 900, 027, Bureau of Ships, April 1944 | ||
Revision as of 22:32, 9 December 2010
This Proposal has not been submitted and may only be edited by the original author.
Pierce Loran.pdf
