June 2023
Author: Forest Pike
Dead reckoning is a method of navigation that involves calculating one’s current position based on a previously determined position, or “fix,” and advancing that position based on known or estimated speeds over elapsed time and course. In the wilderness, dead reckoning can be used as a backup to navigate without the aid of an electronic device should your primary navigational measure (e.g., smartphone app or GPS) become lost or damaged or its battery depleted. Here is an explanation of how to navigate using dead reckoning in the wilderness:
- Determine Your Starting Point: Before you begin, you will need to determine your starting point. This can be done using a map and compass or by taking a bearing on a prominent landmark or terrain feature. Not all landscapes offer easily defined landmarks, so choose wisely as their identifying features can change with perspective as you navigate forward along your pre-planned course. Make sure to record coordinates of your starting point, or “plot” your position, as well as the time you began your journey.
- Estimate Your Speed and Direction of Travel: In order to use dead reckoning, you will need to estimate your speed and direction of travel. This can be done by measuring the distance you have traveled with a pace counter or by measuring the time it takes you to cover a known distance. Your preseason training efforts offer a prime opportunity to identify your average speed of travel with “full kit,” which could prove useful when scouting and hunting seasons approach. Use of a compass is most ideal in determining your direction of travel and ensuring it remains accurate as you progress onward.
- Keep Track of Time: Dead reckoning relies on the passage of time to calculate your current position. Make sure you keep track of the time you have been traveling, either by using a watch or by marking the position of the sun. The rule of “two is one, and one is none” remains true here as having a simple watch in addition to your smartphone or GPS could greatly enhance your navigational abilities should those electronic devices become inoperable.
- Update Your Position: As you travel, you will need to update your position based on your estimated speed and direction of travel. This can be done by plotting your position on a map using a ruler and compass or by referencing progressive landmarks along your way with periodic discipline.
- Check Your Position Against Landmarks: As you travel, keep an eye out for landmarks that you can use to check your position. These can include mountains, rivers, or other natural terrain features. Compare your calculated position to the location of these landmarks to ensure you are on course. Use these opportunities along with the known passage of time to further refine your dead reckoning calculations, and therefore, accuracy.
- Make Adjustments as Necessary: If you find that your calculated position is not in line with the landmarks you are seeing, you will need to make adjustments to your course or your estimated speed.
- Check Your Position Regularly: Dead reckoning is a method of navigation that can be prone to errors, so it is important to check your position regularly. Make sure to update your position at least once every hour, and more frequently if you are in an area with poor visibility or if you are unsure of your course.
- Plan Ahead: While dead reckoning is a useful method of navigation, it should not be used in isolation. Make sure to also have a map and compass, wear a watch as a secondary, and familiarize yourself by means of map study well prior to a backcountry outing.
- Practice: Dead reckoning takes practice to master, so make sure to practice using the method before embarking on a backcountry trip. Try using dead reckoning to navigate shorter trips or in familiar terrain before attempting to use it in more challenging environments.
- Safety: Always make sure to have a well- built plan in place before embarking on a backcountry adventure. Aspects such as ensuring you have adequate gear, adequate human skills, paying attention to weather and other hazards, and informing someone of your plans and expected return time may seem like no big deal, but they certainly are!
Dead reckoning is an essential tool for wilderness navigation should your primary means of navigation fail, but it’s important to remember that it should be used in conjunction with other navigational tools. Always practice and take the necessary safety precautions when navigating in the wilderness.