Word: mls
(lookup in dictionary)
(lookup stats)
Dates: during 1970-1979
Sort By: most recent first
(reverse)
...that in a decade or two all major airports will be served by standardized electronic wizardry that will make landings in the thickest fog as safe and happy as the touchdown of a Piper Cub on a balmy April day. The new device, known as the Microwave Landing System (MLS) is also expected to help unsnarl the aerial traffic that often clogs the skies above major airports today...
...with ones that provide a much larger and more flexible landing approach area (see diagram). Planes under instrument landing control are now brought through the approach area to the runway one at a time in a long single file, like a string of elephants entering a circus arena. The MLS lets planes head into what is, in effect, a huge electronic funnel whose gaping mouth is 80° wide and 20° high (the ILS glide path is only 6° wide and 1.4° high). With MLS, arriving aircraft can enter from several directions at different speeds, flying various...
...disputes the efficiency of MLS, but for three years an increasingly bitter international argument has gone on about whose design shall be chosen as standard equipment for the world. Australia and the U.S., plus France, Germany and Britain, had all had competing designs. By last week, when technical experts from more than 60 countries gathered in Montreal for a meeting of the International Civil Aviation Organization, the struggle had degenerated into a rancorous technological dogfight between the U.S. and Britain. Through the Federal Aviation Administration (FAA), the U.S. was urging adoption of an American-built MLS in which the electronic...
Instead of sweeping beams, the rival British MLS uses a sequence of signals broadcast along arrays of vertical and horizontal antennas. Just as a passenger on a railroad station platform hears a high-pitched whistle as the train approaches and a low-pitched one after it passes by, the approaching aircraft's computer senses an increase in frequency of the radio signals from the horizontal antennas when the aircraft is on one side of the electronic funnel's center line. When it is on the other, a drop in frequency occurs. A similar Doppler shift...
...British, whose Doppler system is built by Plessey Co., Ltd., insist that the U.S. scanning beam is clearly inferior. They also contend that computer simulations done for the FAA at M.I.T.'s Lincoln Laboratory were biased in favor of the American MLS. Some U.S. experts, including a former FAA administrator, John H. Shaffer, agree. But after technical presentations and demonstrations of both devices in Montreal, the ICAO experts voted 39 to 24 in favor of the American system. The U.S. scanning beam has won a crucial round in the quest for a prize that eventually may be worth...