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 Previous: In the Beginning Was the Straight Key: A Chronology of Paddles and Keyers |  Next: FotoGallery |
By Rico Johnston, N5ABQ
July 1, 1999
What use is APRS? Ninety-eight percent of the time it is just an interesting plaything. But the other two percent . . .
On January 20, 1999, a Cessna 210, a single-engine airplane, crashed high up on the west side of the Sandia Mountains near Albuquerque, New Mexico. The cause of the crash is still being investigated. But the weather was lousy--gusting wind, fog and occasional rain and snow. Television news helicopters and a New Mexico State Police helicopter hovered briefly over the site to get footage for the news. Some of the pilots, between flying, handling radios, fighting the wind and avoiding the mountain side, managed to get approximate GPS (Global Positioning System) readings on the site.
It was almost dark when a foot team, Team 1, started up the mountain to confirm the fate of the plane's occupants. At least one person on the team, Bob Rieden, WD5IDL, had an APRS tracker. The APRS tracker is a GPS, a TNC (terminal node controller) and a 2-meter transceiver. The GPS ascertains its position and passes it to the transmitter via the TNC. The position, with other information such as call sign, direction of travel, speed of travel, etc, is transmitted to the world.
At search base, Jim Baremore, K5QQ, had an APRS+SA system set up to track the searchers. The APRS+SA is a program that plots positions received from an APRS tracker onto a DeLorme Street Atlas map. Bob Hufnagel, KA5TAK, and Frank LoGrasso, N5ZUS, handled communications with the team except for the APRS discussions.
Team 1 was travelling some rough terrain and darkness made it worse. Using only the light from their headlamps, they fought their way over, around and under rocks, brush and trees. They had maps, compasses, GPS and the skills to use them, but it would have been time-consuming and distracting.
APRS and good communication allowed Team 1 members to concentrate on their footing, the terrain, and the search. Search Base concentrated on the maps. "Instead of stopping to get out the GPS or map, I would just ask Jim on the radio, 'How are we doing?'" Rieden said.
Using the location reported by helicopter pilots on scene earlier, Baremore guided Team 1 toward the crash site. The crash site and Team 1's locations showed as points on Baremore's computer screen. As new information from witnesses and other pilots came in, the target location was moved. But Team 1's track to the scene was about as straight as it could be given the terrain.
"We did not have to backtrack once," Rieden said. Search Base could tell Team 1, "You need to go due east now, about two-tenths of a mile," --or-- "You are due south of the scene, turn north."
It was obvious that Team 1 was climbing hard because Bob Hufnagel was breathing heavily on his transmissions. He is very fit and an active hiker. It would have been a time-consuming chore to have to read map, compass or GPS in the dark in addition to finding their route.
APRS took the team to within 150 feet of the point of impact, in the dark. All three occupants of the aircraft were confirmed dead. While several team members stayed the rest of the night, the remainder returned to base camp. Recovery of the bodies had to be postponed for four days because of the weather.
Editor's note: WD5IDL, K5QQ, KA5TAK, KC5VWT and the author (N5ABQ) are members of The New Mexico Search and Rescue Support Team. The team encourages members to use APRS often so everyone is familiar with their equipment and its capabilities when it is needed for a search. Readers may contact Rico Johnston, N5ABQ, at ricoj@nmia.com.
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