Jun 8 1976
From The Space Library
The Communications Research Centre (CRC) of the Canadian government's Communications Department in Ottawa announced successful demonstration of a new satellite-aided search-and-rescue concept that could reduce time, fuel-dollar, and other costs associated with conventional ways of finding downed aircraft. The demonstration was funded by the Canadian Department of National Defence. The project, begun in May 1975, used the Radio Amateur Satellite Corporation's Oscar 6 satellite with simulated distress signals to show that crash sites in Canada-and elsewhere in the world-could be pinpointed with accuracies as good as 1.6 km, generally within 3 km, in as little as 15 to 20 min after the spacecraft first heard the signal. The conventional emergency locator transmitter (ELT) mandatory for aircraft in Canada and the U.S. would automatically signal on crash impact, as designed, providing a signal on the international distress frequency of 121.5 hz for at least 100 'hr for search-and-rescue aircraft to home into. The search range until now had been within 50 km of a crash site, flying crisscross patterns involving many planes and dozens of costly as well as risky flying hours.
The satellite system would depend on two things: highly precise orbit predictions (knowledge of the satellite's exact position at any instant) and sophisticated computer processing of distress signals relayed to a ground station. The system works by measuring the Doppler shift in the 'ELT signal frequency as the satellite at about 1100 km altitude passes over the crash site; locations of about 60 "crashes" simulated by transmitters as far away as Winnipeg had been fixed by processing Oscar 6 signals with increasing degrees of accuracy. An operational system would include 3 satellites with a design lifetime of 7 to 10 yr, with total spacecraft and launch costs about $30 million. When the satellite nearest to a crash site appeared over the visible horizon, it would alert ground stations that it had received an alarm; 15 min later, at the conclusion of its pass, an immediate fix accurate within 112 km would be possible, and a position fixing the site within 3 km would be delivered within 2 to 15 min depending on the capacity of the computer. A $3 million annual cost over 10 yr would be only a small part of what Canada was now spending on aerial searches. (CDC release 8 June 76)
Marshall Space Flight Center announced it had used aerial thermal scanning techniques to locate high heat-loss areas as part of its energy resources management program to reduce energy consumption agency wide. The Lewis Research Center had made thermal scanning flights for all NASA centers, and MSFC had been scanned twice, once in October 1975 and again in February 1976, using a C-47 aircraft with onboard scanners that recorded on digital tape the average temperature of each area covered. Fed into a computer, the digital tape produced printouts and live mosaic maps projected on a television monitor to show areas where excessive steam-line losses occurred and to identify buildings losing excessive heat through roof structures. The MSFC facilities office validated the data through visual inspection of steam lines and roof insulation, and issued work requests for repair and replacement of insulation in 88 steam-line locations. Longer range action was planned to repair and replace deteriorated roofing and replace sections of the steam lines. (MSFC Release 76-104)
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