The Back Bearing To Find Your Car
Okay. Last lesson we followed a bearing across open ground to get to something. Now let's flip it around, because this is Low Key the whole point of this class.
A back bearing is how you get home.
Here's the idea. If you took a bearing of, say, 60 degrees to get to that tree or that ridge, the bearing back to where you started is 60 plus 180. So 240 degrees. That's it. That's the math. Add 180 if your bearing was under 180 to start, subtract 180 if it was over. Either way you land on the opposite direction on the dial.
You don't even have to do the math in your head if you don't want to. Some compasses have a mark on the back of the housing that shows you the reverse bearing automatically. But I'd still learn the add-180 trick, because you should understand what your compass is doing for you, not just trust the sticker.
Why this actually matters
Every lesson so far has been about getting somewhere. This one's about getting back. You hike in, the trail forks, fog rolls in, whatever. You know your car is roughly where you started. A back bearing gets you there without guessing.
How to do it, step by step
- Before you leave your car, or your trailhead, or your camp, take a bearing on something. Doesn't have to be fancy. Just note your direction of travel as you head out. Write it down. Actually write it down, don't trust your memory, we've talked about this.
- When you're ready to head back, take that same number and add or subtract 180.
- Turn your whole compass body until the needle lines up in the housing, same as always. Feet planted, compass flat, let the needle settle.
- Pick a landmark in that new direction. A tree, a rock, a saddle in the ridge. Walk to it. Repeat.
That's genuinely the whole skill. It's not harder than a regular bearing. It's just a number you already have, flipped around.
A quick gut check
Before you commit and start walking, look at the terrain and ask yourself if the reverse bearing makes sense. If you hiked up and to the right, the way back should feel like down and to the left. If your back bearing has you walking straight up a cliff, something's wrong. Probably a math error, or you wrote the wrong number down at the start. Trust the terrain to sanity-check the numbers, not the other way around.
Where this saved me
I've told you the ziploc bag thing already, and I'll tell you again, because this is the story where it actually mattered.
I was coming down a canyon a while back and an afternoon storm rolled in fast, like they do here. One minute it's fine, next minute it's sideways rain and I can't see the ridge I'd been using all day. My phone was in my pocket, not in anything waterproof, and by the time I got it out to check, it was soaked and dead. Just gone.
But my map was in a ziploc, and I had a bearing I'd noted on the way up. So I did the math, added my 180, and started walking the reverse. Didn't need to see far. Just needed to trust the number and pick landmarks a few yards at a time. Got back to the trailhead fine, soaked through, feeling pretty dumb about the phone, but fine.
That's why I preach the ziploc bag harder than I preach the compass itself, honestly. Doesn't matter how good you are at bearings if your map's turned to mush in your pocket. Buy the gallon size, it's a dollar, put your map in it before you leave the house.
A caution
Storms move fast up the canyons around here, and cell signal disappears even faster. If weather's rolling in, this is exactly the moment a back bearing matters most and exactly the moment people panic and stop trusting their own math. Don't. If you took the bearing right on the way in, the reverse is right too. Trust the number, walk it, check your terrain as you go.
Practice this at home
You don't need a canyon for this. Stand in your kitchen. Take a bearing toward the fridge. Add 180. Turn until the needle settles. See if you're now facing roughly the front door. Dumb, but it works, and it's the same skill.
Before next time: next time you're out on a walk, even a boring one around the neighborhood, take a bearing when you start and do the math for the bearing back before you actually need it. Get the habit in your hands before the weather makes you need it for real.
Thanks, Jason