This morning I blundered onto an online OnX Offroad map and description of Coyote Road. And that led to finding a trail-difficulty rating for the road the Barkers apparently were on. But I'm getting ahead of myself.....
First, look at the Coyote Road entry....
On X Offroad map of Coyote Road
You'll see a basic description and a trail difficulty rating of "1- Easy" for this 30-mile road to the town of Silver Peak. A map should come into view in the black area at the bottom of the page and start rotating.
The blue line that comes into view is the one we're interested in. Near its intersection with Coyote Road, we see this is the road through Argentite Canyon. The submitter of this route calls it McAfee Road.
Click on that blue line to see its description and trail-difficulty rating of "4 - Easy" (for dirt bikes, ATVs, high-clearance 4X4, and SUV vehicles) for it's 53-mile length, a 5.5-hour drive.
If you zoom in a few times and follow McAfee Road from Coyote Road, you'll see it winds through hills and emerges into lighter-colored area with a few side roads to the left. I believe the RV was found in that area... about a quarter mile up that third side road. (Sorry about that description-- I can't find a way to put a pin there.)
So I'm guessing what happened is the Barkers had their GPS (or app) set for a destination of Nellis Air Force Base near Las Vegas (which Travis said was their next overnight destination). And in the settings of the GPS/app, they had chosen 'shortest distance' as route-calculation method. If the destination had been the town of Silver Peak or a more easterly destination, the GPS would have selected the Coyote Road to Silver Peak.... not because it's faster, but because that would have been the shortest route to that destination.
But they selected a destination well to the south so that means the GPS would try to 'cut the corner'. Instead of routing straight east through Silver Peak to connect with 95 above Goldfield to turn south, it would look for south-trending roads along the way to cut the corner.... like McAfee Road (or portions of it).... to find the shortest distance. This is of course speculation and is based on how my Garmin GPS works.
Another possible explanation would be a bad segment in the routing database used to calculate the route. In such a case, the GPS wouldn't route across the Coyote Road because it didn't calculate as going through.
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