Milestone-Proposal:LORAN: Difference between revisions
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{{ProposalEdit|a1=LORAN|a2a=Cambridge MA|a2b=Boston Section|a3=1940 to | {{ProposalEdit|a1=LORAN|a2a=Cambridge MA|a2b=Boston Section|a3=1940 to 1946|a4=Radiation Laboratory of the Massachusetts Institute of Technology: | ||
In October 1940, MIT was chosen for the site of an independent laboratory that would be staffed by civilian and academic scientists from every discipline. Fourteen months before the U.S. entered World War II, MIT formed, under government contract, a newly Radiation Laboratory began its investigation of radio navigation and radar. The radio navigation division was housed separately from the radar group but was always referred to as Radiation Laboratory. The staff was housed in their own building in Cambridge. On 31 December 1945, the Radiation Laboratory was formally closed and staff members returned to their careers. It should be noted that in 1990, the IEEE Milestone was awarded to the Radiation Laboratory. That Milestone was awarded to the laboratory as a whole, not navigation. | In October 1940, MIT was chosen for the site of an independent laboratory that would be staffed by civilian and academic scientists from every discipline. Fourteen months before the U.S. entered World War II, MIT formed, under government contract, a newly Radiation Laboratory began its investigation of radio navigation and radar. The radio navigation division was housed separately from the radar group but was always referred to as Radiation Laboratory. The staff was housed in their own building in Cambridge. On 31 December 1945, the Radiation Laboratory was formally closed and staff members returned to their careers. It should be noted that in 1990, the IEEE Milestone was awarded to the Radiation Laboratory. That Milestone was awarded to the laboratory as a whole, not navigation. | ||
Our Proposal: | Our Proposal: | ||
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A full and complete description of the evolution of loran is provided in the attached article by JA Pierce entitled | A full and complete description of the evolution of loran is provided in the attached article by JA Pierce entitled | ||
"An Introduction to Loran", Proceeding of the IRE, 1946. Reprinted by IEEE AES Magazine 1990. | "An Introduction to Loran", Proceeding of the IRE, 1946. Reprinted by IEEE AES Magazine 1990. | ||
INSERT PIERCE ARTICLE HERE. | INSERT INSERT INSERT | ||
PIERCE ARTICLE HERE. | |||
The Gee System in Britain | The Gee System in Britain | ||
At the time that loran was being designed, there existed in Britain a similar navigation system being developed called Gee. Gee was also a pulse-modulated hyperbolic navigation system, similar to loran. Gee operated at ultra-high frequencies and was limited to line-of-sight distances, of 400 miles or so. Gee was intended for aircrafts traveling short distances; not long sea voyages. In mid-1942, R. J. Dippy, who had invented the Gee system, came to the United States for eight months to assist in loran development. Pierce admits that Dippy's basic concept was borrowed by American scientists working on long-range navigation but not Gee designs and nor techniques. He acknowledges that "Loran copied gee's concepts rather than techniques and may be said to have been invented in America in the sense in which Galileo is said to have invented the telescope". | At the time that loran was being designed, there existed in Britain a similar navigation system being developed called Gee. Gee was also a pulse-modulated hyperbolic navigation system, similar to loran. Gee operated at ultra-high frequencies and was limited to line-of-sight distances, of 400 miles or so. Gee was intended for aircrafts traveling short distances; not long sea voyages. In mid-1942, R. J. Dippy, who had invented the Gee system, came to the United States for eight months to assist in loran development. Pierce admits that Dippy's basic concept was borrowed by American scientists working on long-range navigation but not Gee designs and nor techniques. He acknowledges that "Loran copied gee's concepts rather than techniques and may be said to have been invented in America in the sense in which Galileo is said to have invented the telescope". | ||
Conclusion: that Gee was not available nor was it an acceptable alternative to loran.|a6=Obstacles during the course of the project were accepted as is or resolved. Secrecy had to be maintained throughout, probably making things worst. The following conditions or obstacles had to be dealt with: | |||
Obstacles | |||
1. Loran stations were often in remote isolated area, making field construction difficult. | 1. Loran stations were often in remote isolated area, making field construction difficult. | ||
2. Cooperation among different countries was required: Canada, Denmark, and Britain, for example. | 2. Cooperation among different countries was required: Canada, Denmark, and Britain, for example. | ||
3. High reliability requirements: In his article, Pierce describes the features taken into account during the design because of high requirements for continuous service. He states that the transmitters worked satisfactorily within specified limits “99 percent of the times”. That's pretty impressive for first generation equipment, considering that loran transmitters are synchronized and operate in pairs. Because the time at which the slave pulse reaches the master station is known, the master station continuously monitors the slave pulse. If a discrepancy is detected, the master alerts the slave station. Either station can initiate a trouble alarm to navigators warning of a potential problem. | |||
3. High reliability requirements: In his article, Pierce describes the features taken into account during the design because of high requirements for continuous service. He states that the transmitters worked satisfactorily within specified limits “99 percent of the times”. | To simplify maintenance, all units were in duplicate with provisions for quick interchange of operating and stand-by units. Overlapping coverage, multiple timers, were provided. Shielded rooms were used to protect timers from interferences. | ||
To simplify maintenance, all units were in duplicate with provisions for quick interchange of operating and stand-by units. Overlapping coverage, multiple timers, | |||
4. Living at remote isolated loran stations: Loran stations were often isolated, remote, dreary places. One website explains as follows: | 4. Living at remote isolated loran stations: Loran stations were often isolated, remote, dreary places. One website explains as follows: | ||
" The crews of | " 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, in addition to the electronic technicians who operated and maintained the transmitters. Each station was commanded by a commissioned officer, usually a lieutenant, with a chief petty officer as second in command. Prospective commanding officers were given a short training course in loran and administration before assignment. Many young men 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." (*) | ||
5. Training operators and navigators: A great number of radio operators and technicians from the US and other countries had to be trained on how to operate the new navigation transmitters. Equally important, navigators aboard ships and aircrafts had to learn a whole new way of doing things to find their | 5. Training operators and navigators: A great number of radio operators and technicians from the US and other countries had to be trained on how to operate the new navigation transmitters. Equally important, navigators aboard ships and aircrafts had to learn a whole new way of doing things to find their position.|a7=It should be noted at this time, that the radio navigation Loran project was not carried out at the iconic "Radiation Laboratory" building home of radar / microwave innovations. Instead, the project engineering team worked in the Hood Building in Cambridge, close to but off the MIT campus. Further research will be carried out to locate this building. Rad Lab was awarded an IEEE Milestone .......... | ||
|a7=It should be noted at this time, that the radio navigation Loran project was not carried out at the iconic "Radiation Laboratory" building home of radar / microwave innovations. Instead, the project engineering team worked in the Hood Building in Cambridge, close to but off the MIT campus. Further research will be carried out to locate this building. Rad Lab was awarded an IEEE Milestone .......... | |||
The proposed milestone plaque could be mounted on MIT Building N42, on Massachusetts Avenue, close to where the original Hood Building used to be. The Boston Section Milestone Committee is currently seeking approval from MIT to carry this out | The proposed milestone plaque could be mounted on MIT Building N42, on Massachusetts Avenue, close to where the original Hood Building used to be. The Boston Section Milestone Committee is currently seeking approval from MIT to carry this out | ||
Revision as of 00:30, 15 December 2010
This Proposal has not been submitted and may only be edited by the original author.
Pierce Loran.pdf
Loran1.jpg .png
Loran_chart.png
This is a test
