Knowing how to use different forms of navigation is something all Search and Rescue members practice on a regular basis. Whether using map and compass, a GPS unit, or even a cell phone (Gaia and Avenza are great apps), understanding how to input and read coordinates, how to find a bearing between two coordinates on a map, and even how to switch from Lat/long to UTM are perishable skills.
Most SAR teams use a coordinate system called UTM (Universal Transverse Mercator), which divides the world into grids and goes into finer detail within that grid to get precise coordinates. Looking at the map below, we can see that Clark County, Washington resides in the “10T” grid. If we were doing a search in Spokane, we would be in the 11T grid. For more information on how the UTM system works, here’s a link to a great video:
During September’s training, a three-lane course was set up for teams to go through. Following Lane One, the team started out with UTM coordinates under WGS84 datum. There’s also UTM NAD27 and NAD83, all of which are common geodetic datums used within North America, with WGS84 (World Geodetic System) being the most commonly used in Search and Rescue. They then had to switch their devices to Latitude/Longitude (degrees, decimal minutes), then did a few routes using map and compass…. measuring the distance to the next point once the coordinates were marked on the map, then figuring out which direction of travel and following that bearing. Also, how to go around an impassable area to continue the bearing on the other side.
All this training is great practice for the searchers. To relate this to an actual search, upon arrival searchers will get put into teams and sent out to cover different search areas. They may be given a UTM coordinate, and once they get to their area, they may have to use their compass to stay on a bearing for a line search until they reach their designated coordinate. When they clear their search area, they can be reassigned and would have to navigate to that new location. If anything is found that may be useful in the search, coordinates are marked and read back to base.