Day 274: Survival Preparation. GPS and Maps. Tasks 15
By: Bob Mayer
Tags: Preparation, Maps, Life Hacking, Pandemic, Survival

GAIA

Do you have a physical road map in your car?

A key step in conducting an Area Study is to have maps. Actual, physical maps. We are a society that is overly reliant on technology in many ways. Cell phones for communication are one. GPS for navigating is another.

GPS stands for Global Positioning System. A basic understanding of GPS is useful so we understand what it can and can’t do.

Let’s get a little geeky. The GPS receiver gets a signal from each satellite with the exact time it is sent. By subtracting the time the signal was sent from the time it was received the GPS receiver can calculate how far it is from the satellite. The receiver knows where the satellite is in orbit so it has a fix on that satellite. For our GPS receiver to work it needs to make contact and get a fix with at least 3 GPS satellites for a two dimensional fix (latitude and longitude) and 4 satellites for a three dimensional fix (adding in elevation). If you are only getting 3 satellites and aren’t at sea level, your actual location could be different from what the GPS is showing. If you’re up at a high altitude in the mountains, this can become significant. Usually, though, this isn’t a problem. Of the 31 active GPS satellites, there are usually 6 in range from most places on the Earth’s surface.

Ever notice that it takes your GPS varying amounts of time to get a fix? If the GPS hasn’t been on recently it could take as long as 30 seconds. Tall buildings or other obstructions can also make it take longer. Most GPS accuracy is to within 5 meters.

Cellphone GPS units act a bit differently incorporating Assisted-GPS to get a fix quickly. They use cell phone tower data to assist. Sometimes they can give you a fix without even accessing satellites. This only works though it you are in cellphone and Wifi coverage.

Another thing to consider is whether the map coverage you’re using is in your device’s memory or downloading. Ever have the GPS map become blank when you’re out of coverage? We should always download our local area tiles for whatever mapping GPS we use. When I plan trips, I download the map tiles into memory for the route and destination. This allows the GPS to work faster and gives me a map even if I can’t download it live. For your vehicle’s GPS, are the maps you’re using in the memory or downloading? Put them in the memory.

I’ve noticed when biking and using GPS that every so often it will tell me it has lost the signal. Some of these ‘dead spots’ are the same, but others seem random. Which brings me to this significant point: you can’t count on GPS!

There are other problems with GPS:

They need the satellites working. EMP — electro-magnetic pulse, whether natural (solar flare) or man-made (nuclear weapon) can wipe those satellites out.

The GPS receiver, whether in your vehicle, a cell phone or handheld GPS receiver, requires power to work. Cell phones and batteries can die. Commercial airplanes are required to have backup navigation to GPS. Just in case. We need to do the same.

Sadly, many people no longer carry paper maps in their car. Beyond that, many don’t know how to read a road map, never mind a topographical one.

When I was a brand new butter-bar second lieutenant in the First Cavalry Division, I was told succinctly that a platoon leader had to do two things well: Maintain communications on the radio and navigate. Failing either of those two and your time as leader was limited and your career in the Army over.

In a survival situation, especially moderate to extreme, it is highly likely you will have to move from point A to point B. It also possible you won’t have a GPS to do that with.

Have a road map as a backup. I keep a Rand McNally binder with maps of North America inside my Jeep. It gets used so much (even when I have GPS because I like to wander) that I buy a new one every year because a few heavily perused pages get worn out and torn, not that I’m blaming Cool Gus (my yellow Lab) who sometimes sits on it in the passenger seat, but I’m blaming Cool Gus.

While Rand McNally is great for your car, get topographic maps of your locale. The scale you want for local area is 1:24,000. You can download and print out maps at this scale for free from the sites below. You can also buy a large map book of your state with topographic maps.

For the National Geographic maps it’s pretty cool because you can download the maps in sets of five where the first is an overview of the quadrant, then the other four are printer sized. Print out in color!

You can also get maps from USGS. These maps allow you to pick the details you want. You can get different scales. 7.5 minute is 1:24,000. Which means one inch on the map equals 24,000 inches on the ground or 2000 feet. 15 minutes is 1:63,360.

Task Fifteen

Mild: GPS/Map Checklist

Get a road atlas for each car

Rand McNally Road Atlas. https://amzn.to/36IVqA9

National Geographic Maps:

http://www.natgeomaps.com/trail-maps/pdf-quads

USGS Maps: http://nationalmap.gov/ustopo/

Get a waterproof map case to put your topo maps in, with dummy cord.

Waterproof map case. https://amzn.to/34yYE6N

Get a topographic atlas of your State

DeLorme Tennessee Atlas & Gazetteer: https://amzn.to/3dbMyo8

Download the map tiles for your area of operation for your car GPS (if possible), your phone, and handheld GPS (if used).

The topographic maps should include your immediate area. If you believe you are going to have to evacuate, get maps covering the route and your BOHS. Then get a waterproof map case.

Get a dummy cord (a piece of 550 cord works fine) to tie the map off to you. The one above already comes with a cord. Seriously. I can’t tell you how many times that dummy cord kept me from being stupid and losing my map. In fact, tie off all important items. I clip my Jeep key to the loop on my pants every time I get out of it when I’m out in the wilderness. I don’t trust putting things in my pockets.

You can order laminated, waterproofed maps, but they are more difficult to carry because of limited folding. This is a judgment call on your part. I prefer the paper map inside of a waterproof map case. For geeks, you can get a pocket protector and alcohol pens to write on the case and the special eraser for the writing when you’re done drawing and then . . .

You can order topographic maps by states. I keep this in my Jeep to back up my road map. You can also go to your local camping store or local bookstore and you should be able to get the pertinent sets of maps. I also own maps of National Forests and National Parks I visit.

There are numerous navigation apps. Google Maps is familiar to almost everyone. There are several topo map Apps you can get. I’ve used a number over the years but the best one I’ve found is Gaia. The basic app is free and then there are two levels of membership. The premium, which is discounted 20% via my affiliate link, (donated to Special Operations Warrior Foundation) is $32 for a year but for the number and types of maps you get, it is definitely worth it. One useful thing to using any map app is to download the map tiles you want to use beforehand (when you’re out in the wilds with no signal) and you learn how to use the app.

Gaia also sends interesting email updates on various outdoor activities that are very informative from outdoor experts.

Land Navigation is covered in Survival.

Feeling a bit overwhelmed about the Area Study? Here’s the easy way to do it. Start from your house. Then move outwards. Do the same with your work. Look at the route from home to work/school. And your Emergency Rally Point. And BOHS. A lot of the information will overlap.

Check one thing at a time. Write down your observations. You’ll be surprised at the amount of information you end up with and how much wiser and mentally prepared you will be than you were. Make sure you ‘disseminate the information’ to your A-Team. Actually, what’s best is if you break down the Area Study and have different members of the team do different parts. Then brief each other. This can be an enlightening and fun exercise.

Once you have the Area Study done, adjust your planning and preparedness to fit the order of likelihood of emergencies and disasters. I cover emergency route planning, which is critical in the Preparation Guide.

The Green Beret Pocket-Sized Survival Guide

Green Beret Preparation and Survival Guide.