HowardDeeversDEAD RECKONING, GPS STYLE

Howard Deevers

Early in our aviation training, navigation is an important subject. Many of my beginning students get lost easily. That is understandable, since things do look differently as we get up in the air. Suddenly, the road we use to reach the airport does not look the same. Get a little further away from the airport, and some beginning students can’t figure out how to get back to the airport. It is all part of the training and earning your wins.

For some reason, I’ve never had that problem. Well, almost never. There were times when I was confused about where I was, but after consulting my sectional (remember those?) I was able to figure out where I was, and where I needed to go. My instructors spent a bit of time on navigation by “ground features,” then we quickly went to navigation by use of VOR’s and NDB’s. Most of the early training planes had at least one VOR receiver, and maybe a NDB receiver. GPS navigation was only a gleam in someone’s mind.

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Dead reckoning was, and still is, used by ships at sea. The term comes from “Ded,” for Deduced Reckoning, which is a method of calculating your course by estimating speed and direction by compass. Sure, modern ships are equipped with GPS, also. GPS is so common now that almost every airplane has at least one in the cockpit, handheld or panel mounted. After getting my pilot’s license, I would practice cross country travel by dead reckoning only, just to keep those skills as useful as possible. Most of my VFR or IFR cross country flights were from VOR to VOR along Victor airways. Now, I file and fly “GPS Direct” and ATC is okay with that. I must say that GPS Direct has its benefits.

This month I had a chance to fly with a friend on a flight that was going to take him from Tucson to Indianapolis. Weather was a factor and we spent a lot of time planning the best route to keep us away from heavy rain, thunderstorms, restricted areas, and MOA’s. We stayed VFR for as long as possible, and we used ForeFlight and his panel mounted GPS for navigation. ATC was very helpful keeping us out of weather and the restricted areas in New Mexico.

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Finally, it was no longer possible to maintain VFR, and we asked ATC to convert the VFR flight plan to IFR. Since we are both instrumented rated, and the plane was well equipped, I felt comfortable doing this. Our good friends at Albuquerque Center helped us out with the request. After only a few questions, we closed the VFR flight plan and were on an IFR flight plan. Only 500 feet of altitude change was needed to be on the correct IFR altitude, and we were cleared direct to our destination: Dalhart, Texas. For the next hour or more we were in solid IMC conditions, navigating by GPS. I thought about that at the time. What if the GPS was not there? What would change? We would stay on the same heading, and fly for the same amount of time, to get to our intended destination. It would be “Dead Reckoning” in IFR.

Our destination was VFR, but we did an instrument approach anyway. For the rest of the trip we were able to maintain VFR over broken to scattered clouds and navigate GPS direct. Flying with GPS has benefits, and for long cross country flights you can’t beat it.

What did the early aviators do? There was NO radio navigation, NO GPS, NO radar, NO VOR’s. They had to rely on their own senses, a compass, a clock, and by looking at the ground to find their way across the country. Charles Lindberg flew from New York to Paris with nothing more than a compass, a clock, and only a few “maps” that were crude compared to what we have today. Navigating “by the stars” has been around for a long time, and is still important, if you know how to use a sextant. During and after WWII, electronic navigation improved rapidly, and today we have the benefits of the GPS system.

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Would we be lost without it? The answer should be NO! Since we all know that the GPS system can be shut down, or even compromised to the point of being unreliable, we need to keep those cross country Dead Reckoning skills sharp by practicing. Remember, safety is no accident. We need to keep current, and don’t forget to look for the next Safety Seminar presented by your Arizona Pilots Association and bring your “Wingman,” too!

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