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Boring, We Know Thy Name: GPS Navigation

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My student Jordan and I did a longish—70 miles—cross country in the Cub last weekend. It confirmed what I've always believed to be true: The essence of navigation is and remains map reading and second, GPS takes all the fun out of it. A third truth also emerged: Cubs aren't just slow, they're stupid slow. But that's what makes them fun.

We flew from Venice to Zephyrhills on a sort of mashup of pilotage and dead reckoning. Technically, dead reckoning should involve headings and requires a watch and a compass. Our Cub has one of those. Sort of. But between its deviation errors and the Cub's kite like dips and swirls, it's all but useless. So we flew pilotage along a plot line drawn on the chart with checkpoints at 10-mile intervals. As a nod to tradition, we had along a conventional E6B, but we did all the calculations on a virtual E6B app on an iPhone. (Hey, let's not get too romantic about any of this)

We flew the trip at 500 feet, the Cub's natural best altitude. I haven't done this kind of flying in, well, forever, and was surprised at the lack of detail on a sectional when you're at 500 feet. I'd meant to bring a roadmap, but forgot it. At that altitude and 60 knots, you see everything below you—and also the Hawks and Herons above you. But there are ground details you can easily resolve that the sectional doesn't depict, like a pattern of lakes and ponds, a small two-lane road and an abandoned railroad track. It was challenging to hand the sectional back and forth and calculate estimates to the next fix. Jordan nailed the course all the way, with a few minor corrections. Top groundspeed was 64 knots, the lowest 58 knots.

Twenty-something blogs ago, I surmised that the right way to teach modern navigation is to combine GPS with detailed map reading. I am hereby withdrawing the idea, because making it work goes against the grain of human nature. For our return trip, we used a portable GPS and rather than the plot line, we flew the magenta line. As far as continuing pilotage is concerned, pushing the direct-to key might as well be the equivalent of pushing a button labeled, "disengage."

You still look out the window and at the ground, of course, and you observe details, but with the GPS doing all the work, the lazy thing to do is not bother to relate what you see to position on the map. Your GPS position is 22 miles from the destination, not two minutes early and a half-mile east of checkpoint 6. The map method is granular, the GPS more of a grand sweep. Truthfully, I prefer the map method over the GPS, which was, well, boring.

I know, I know. I'm turning into the man my father warned me about. Must be coded in the DNA somehow.

Comments (36)

In the modern world of airspace restrictions and TFR's, even being 1/2 mile east of intended route at 500' can have consequences. Not sure if I would want to give up boring for some interception excitement... YMMV

Posted by: Mark Fraser | November 19, 2010 2:02 PM    Report this comment

Since you are traveling at 1/2 to 1/3 the speed of most GA airplanes the risk of inadvertently wandering into airspace you don't want to be in is much lower. You just don't cover that much ground.

The waves of anxiety and relief of finding the next check point when you don't know for sure if you are on it until you are practically on it, epecially in sparsely populated areas, is what makes using a map in a cub much more fun. You also come to really appreciate the comfort of the water tower name matching the town that you thought you were over on the map.

Posted by: Mark Jensen | November 19, 2010 5:18 PM    Report this comment

I once flew my cub from Fernandina Beach to Charleston SC no map necessary just follow the islands. I did use a handheld to get a good groundspeed to judge a fuel stop. (St Simons or Hilton Head) I figured any groundspeed greater than 70 knots would allow a Hilton Head stop. 75 knots on the way up worked great, but bumpy at 500 feet. I would not have had the confidence in my time and distance e6b groundspeed calc to make HHI. On the way home 55 knots and smooth as glass, two stops HHI and SSI, but worth every second. I did this flight in 1996 remember like yesterday. Foreflight for iPad may have worked for both chart and gps? By the way all cub postings to date are dead on especially the pattern discussion.

Posted by: Jack Healan | November 19, 2010 7:08 PM    Report this comment

I was surprised how accurate this navigation method turned out to be, once we got a decent hack on the groundspeed. The slow speed is both a pain and a benefit. You have plenty of time to examine ground features before relating them to chart. Here in Florida, the vis is always good--even when it isn't--so seeing the checkpoints and avoiding airspace is easy.

Posted by: Paul Bertorelli | November 20, 2010 5:28 AM    Report this comment

It is great to see that you are teaching the grass roots of navigation. For me it is the only option. I was wondering if you went around those towers at Bloomingdale or if you gained altitude and went over them? I was glad to see you before your trip to ZPH at the Young Eagles rally. I do hope that you will attend our chapter Christmas party Dec.5.

Posted by: Bebe Teichman | November 22, 2010 7:19 AM    Report this comment

I just did a 400 mile XC in marginal VFR with no GPS. It's a helpless feeling when you're wandering around patches of weather and then try to get back on course. It's a doubly helpless feeling when tower asks "how far out are you" and the best you can do is guess.

GPS is a wonderful tool. I re-learned again this weekend that it's dumb to leave it behind and trust that everything will go "as planned". I'll never leave it behind ever again.

Thanks for the education. I may buy a second. Never again.

Posted by: Mark Fraser | November 22, 2010 7:30 AM    Report this comment

I was on a cross country from FL to VA a few years ago. When I got to Lake Marion, SC the weather closed down to MVFR. I had no GPS and was too low for reliable VOR reception. I used the sectional and the original planned heading to cover most of NC until I got to familiar landmarks.

It's a trip I'll never forget! I'm glad I had the pilotage skills to make it a success. You alway need to be able to fly the airplane with a compass, altimeter and sectional.

Posted by: Meredith Hutto | November 22, 2010 7:49 AM    Report this comment

Paul, I find it hard to navigate well in my Cub. I think it is likely due to the tendency to look out the door and down at the scenery. Instead of ahead at distant landmarks and the compass. The little airplane symbol on my GPS keeps me headed in the right general direction.

Posted by: Jake Jacoby | November 22, 2010 9:01 AM    Report this comment

I grew up on E6B's, taking the times between two check points on the ground, putting a pencil between two points on the map and then sliding the pencil over to a VOR circle to get the course between the points. Then taking the same pencil and marking the lines of latitude to dt the distance. In later years, I would pull out the "circular slide rule" and check the FMC of the 777 to see if it was right. :)

One of the best moments was when Neil Armstrong was using time/distance over two checkponts during the lunar landing and realized they were coming in too high. Loved it.

Posted by: James Gombold | November 22, 2010 9:59 AM    Report this comment

As a grad student in aerospace engineering at Auburn University in 1969-70, I taught an Aviation Management course "Guidance and Control". I gave the students a choice: write a term paper or do a "project".

The project was to get together with two other students and a flight instructor, and to take turns flying right seat as they navigated a cross country flight with three legs with VOR, NDB, and pilotage each used on one leg.

As you might guess, after teaching this course for 5 consecutive quarters, I never got any term papers. However, I did get rave reviews of the navigation experience. The students learned to apply what was taught in the classroom, actually experiencing the pressure of moving along at 100+ knots while problem solving. They usually worked as a team with the back seaters sometimes helping the "copilot" . Navigating over eastern Alabama and western Georgia at low level by ground reference is challenging - you look outside and see miles and miles of green trees in all directions with few distinctive landmarks until you find a town. Roads, railroads and rivers are sometimes difficult to see until you're almost overhead. When I moved to California, pilotage was like cheating - look outside in most of the state and you know where you are because of the distinctive landmarks.

We still need to be able to do it the old fashioned way, but for me, that's (hopefully) only going to be just for fun.

Posted by: Walt Woltosz | November 22, 2010 10:55 AM    Report this comment

We went between the towers, actually. There are now nine of them, in clusters. Guy lines plainly visible and they're maybe a half mile apart.

Posted by: Paul Bertorelli | November 22, 2010 11:05 AM    Report this comment

I have a Luscombe, and all it has for navigation is a compass, and a clock with a sweep second hand. I have flown it from coast to coast and boarder to boarder. There is nowhere that I would not go with it. Sadly, the art of map reading for the most part is not being taught or emphasized as it was in past decades. Yes, you can navigate accurately with a chart/map. I have flown in parts of the world with just a chart/map where the consequence of straying off course was being shot down without warning. It is a great break from all the high tech toys.

Posted by: Vernon Childers | November 22, 2010 11:12 AM    Report this comment

Sometimes the scattered low, non-descript mountains of the Southwest can be confusing, and all the Moa's too, but I like the challenge and am one to hold a map in my hand most of the time. (weather here frequents as often as hurricanes do) Oh, I occasionaly nick a forbidden zone corner, but mostly stay away from them. But your blog also made me consider, tho I love my bubble canopy and the vis, sometimes I envy those who can see the ground go by like in your Cub.

Posted by: Dave Miller | November 22, 2010 11:38 AM    Report this comment

Why 500 feet (or less) AGL unless weather was a problem? VFR nav with a chart is best done at about 3000 AGL. At that height sufficient detail is discernable, but you have a range of view around you and ahead to help orient you and give you a better aiming point. Learned that while training in the Pterodactyl for my PPL.

Several years ago I was on my way to SNF on the last leg to Lakeland, fat, dumb, happy until electrical system died and the GPS along with it. Surrounded by lostness I eventually managed a visual re-orintation that led to Zephyr Hills where I left the plane to be repaired while at SNF.

Posted by: David MacRae | November 22, 2010 1:44 PM    Report this comment

"Sadly, the art of map reading ...is not being taught or emphasized as it was in past decades"

True, but neither is dope and fabric repair nor LORAN or ADF for private pilots. When GPS is now less than the cost of a tank of gas then there is no reason to go back to horse-and-buggy compass and watch. It can be fun (but it's not efficient nor easy nor particularly safe when other things go wrong).

Posted by: Mark Fraser | November 22, 2010 2:15 PM    Report this comment

"Why 500 feet (or less) AGL unless weather was a problem? " David, based on this question I'm guessing that you have never flown a cub with 65hp on a warm day with a passenger. You may be at your destination before you reach 3000 ft. You also can't smell the grass and crops as well way up there. It is harder to wave at people too.

Posted by: Mark Jensen | November 22, 2010 3:34 PM    Report this comment

I'm guessing that you have never flown a cub with 65hp on a warm day with a passenger. <<

I think you have to do this to really appreciate it. 'sides, with the door open, it's warmer at 500 feet than 3000 feet. And one just doesn't close the door. Also, at that altitude, our groundspeed would have 30 knots.

I found the trick with the map at 500 feet is stay on it, constantly comparing the map to the terrain. Once the SA snaps in, it's pretty easy to keep it and know exactly where you are all the time. The GPS is superfluous.

As I noted, you do notice that the map doesn't have a lot of features that you can actually identify on the ground. But there are enough to make it work. Helluva lot of fun.

Posted by: Paul Bertorelli | November 22, 2010 4:31 PM    Report this comment

<>

Well, actually, I have, as well as other low/slow aircraft. If you are just knocking around locally, and know the area, sure 500 beats 3000 any day for fun. But if you have to go somewhere new and landmarks are fewer, and you want to go there in a predicable straight line, higher is better, but not too high.

Lived in Australia for several years, flew all over the continent using only WAC charts, never turned the VOR/Nav on. GPS was only a gleam in someone's eye. My personal best was a 400 NM leg over a featureless desert hitting my target within a mile. I'm not saying that others have not nor will not do better. I'm just agreeing that pilotage without GPS can give one a lot of satisfaction. Even if you do it at 3000 feet where you have a chance to take the odd moment to look around....

Posted by: David MacRae | November 22, 2010 5:01 PM    Report this comment

"I'm guessing that you have never flown a cub with 65hp on a warm day with a passenger...."

Well, actually, I have, as well as other low/slow aircraft. If you are just knocking around locally, and know the area, sure 500 beats 3000 any day for fun. But if you have to go somewhere new and landmarks are fewer, and you want to go there in a predicable straight line, higher is better, but not too high.

Lived in Australia for several years, flew all over the continent using only WAC charts, never turned the VOR/Nav on. GPS was only a gleam in someone's eye. My personal best was a 400 NM leg over a featureless desert hitting my target within a mile. I'm not saying that others have not nor will not do better. I'm just agreeing that pilotage without GPS can give one a lot of satisfaction. Even if you do it at 3000 feet where you have a chance to take the odd moment to look around....

Posted by: David MacRae | November 22, 2010 5:04 PM    Report this comment

Yes, it can be done.

Posted by: bob long | November 23, 2010 10:01 AM    Report this comment

Now we know what happened to “Wrong Way Corrigan” He did not have a GPS! Then there is Charles Lindbergh. How he made it know one knows. Of course, Amelia Earhart could have used a $99 GPS. And by the way, I do not believe dope, fabric repair, LORAN, and ADF was ever a requirement for a private pilot certificate. It was not when I received my certificate in the late 50’s. GPS is just another tool. There is pro’s and con’s to everything that we do in life. We get in trouble when we have a hammer and everything looks like a nail.

Posted by: Vernon Childers | November 23, 2010 11:13 AM    Report this comment

Sure, the VOR works better at 3,000 feet but I can read the road signs much better at 500 feet.

Posted by: Richard Montague | November 23, 2010 1:12 PM    Report this comment

"Sure, the VOR works better at 3,000 feet but I can read the road signs much better at 500 feet."

Ha Ha! Especially the one that says "Tunnel Ahead"...

No VOR needed. The Pterodactyl didn't have one, and in Aussieland there weren't enough of them to be useful in those days. Virtually none in the outback, i.e., any place more than 50 miles from the coast.

Posted by: David MacRae | November 23, 2010 2:02 PM    Report this comment

I have NEVER been to 3000 feet in my 65hp Cub. I'm not sure I would have enough gas to get that high!! 500 ft over the ground does make navigation tough. 1000 ft is way easier, especially with a Rand-McNally on board. Anyway, putt-putt navigation is fun and a challenge. I did fly at 4500 ft a week ago in some heavy metal (C-150) but would never try that in the Cub, in the summer, with another human in the front, with the door open..... not gonna happen!

Posted by: Mark Mayes | November 23, 2010 5:07 PM    Report this comment

My first plane was a Luscombe with a VHT 3 later a cub with a compass and no radio. Here in central florida you didn't need either one back in the sixties it was vfr almost always and cities and familiar airports were only minutes from each other. Today even though I am still living here I file IFR. The regulatory environment of today is no were as forgiviing of inattention and honest mistakes. VFR at least in florida and the north east requires you really know were you are at all times or you will be hearing from the "Gotcha" Police

Posted by: Jim Renfro | November 24, 2010 7:27 AM    Report this comment

We regularly fly long cross country flights (1/3 of the way across the country) in the J-3. We're usually low as that is the Cub's natural environment. The GPS is excellent for making sure we know precisely how long it is going to take us to get to the next fuel stop v. how many minutes of fuel we have on board (12 gallons, 4 gph doesn't give you much wiggle room). Charts are limited in their usefulness at 500 feet. Roadmaps are very useful and a great geography lesson. We consider the GPS an essential tool for efficient travel and no-sweat fuel management) but wholly agree that one should do a Ferris Bueller and look around a bit or the best stuff will just pass you by....

Posted by: Jeff Russell | November 24, 2010 7:57 AM    Report this comment

UP to 3000'? Where I live 500AGL is 6500MSL and pattern altitude is 7000.

How I envy you lowlanders with your high performance atmosphere!

Posted by: Mike Hand | November 24, 2010 8:27 AM    Report this comment

I recently had an article published in EAA's online Sport Pilot magazine; I am very experienced ex-USAF Navigator and address this issue. Do I need a GPS-NO, but I will not fly without a GPS because it is safer and makes for much more effective sightseeing. In years passed I have seen the GPS lose signals at least twice and as I follow with a chart, it was an annoyance, not a problem. Mr. Bertorelli's article is interesting, but not my cup of tea...

Posted by: Kenneth Nolde | November 24, 2010 8:28 AM    Report this comment

I am young, and I learned to fly 11 years ago in planes with GPS. I've never known different. While working at AOPA, I was blessed to fly with some very awesome avionics. WAAS, ADS-B, glass, etc. I love them, and I can't wait to see where we go.

6 months ago I bought my first plane, a Decathlon with nothing more than a compass. No VOR, one radio. Dreams of Aspen, 696s and iPads instantly entered my mind. However, after a 14 hour cross country bringing it back with sectional and clock: no more!

I'm done with that kind of flying. I had more fun being off a little, wandering around, and looking outside than is possible with a magenta line. Not lost, not in danger of violating airspace, etc. Yes, it was less efficient, yes, we had to leave bigger safety margins, and yes, it was some of the most fun I've ever had in an airplane. We had a GPS tucked in the backseat if needed, and I still carry one sometimes for emergencies, but not for navigating! Look out and fly!

Posted by: Claire Kultgen | November 24, 2010 11:36 AM    Report this comment

Good for YOU!If I have a wide verity of carpenters tools and only proficient with one or two tools, it does not make me much of an accomplished woodworker does it.

Posted by: Vernon Childers | November 24, 2010 11:50 AM    Report this comment

These comments are great. Glad to see the art of pilotage is not lost. In this era of glass cockpits and GPS, it is too easy to forget how to use this fine art. I hope all you CFI's out there are teaching the basics as well as the glass.

In today's world, we need both, as electronics do fail, and batteries get weak. Keep the comments flowing.

Thanks Paul for starting this blog.

Posted by: James Gombold | November 24, 2010 12:31 PM    Report this comment

Paul, I love reading about your transition to uncontrolled, low and slow flight. I am doing the same thing and I believe many other pilots will as well. I don't have a good solution for keeping the map in my lap with the doors off though. I have contributed at least one map to a farmers field and having it go through the prop is probably not a good idea either. My airplane will not fly itself so I need to keep one hand on the yolk, another on the throttle and both feet on the rudders. I don't have a third arm for a map. Any ideas?

Posted by: Dana Nickerson | November 24, 2010 2:27 PM    Report this comment

For floppy maps.....you can use a knee board. Also, in our Cub, there is a pouch on the back of the front seat. I can stick a sectional in there and wedge it so that it doesn't (usually) fly out of the plane. You can also fly with just your feet and use both hands to manipulate maps for a while. My son asked my once why I just flew with my feet in cruise and I wasn't really aware that I was using my feet more than my hand. Anyway, when I learned tailwheel, my instructor (Tony Markl), was adamant that I learned to navigate down low and slow. I learned a lot from Tony. I do carry a GPS at times but prefer not to when out Cubbing, although in the NE there are a LOT of places that you should not stray unless you want the FAA to smite thee. Paul, keep the Cub stories coming. There are a lot of flying basics that flying a relic reinforces.

Posted by: Mark Mayes | November 24, 2010 3:57 PM    Report this comment

Ah, I remember the 'good 'ol days' of 'dead recogniting' using a compass and a map (I"m 73) in an old Luscombe Silvaire..

Posted by: Bernie McAda | November 24, 2010 8:46 PM    Report this comment

It is always good to expose your students to more than is required for the PTS. Basic navigation skills are always important. I managed to get a 65HP &AC Champ to 10,000 feet one day doing a bit of thermaling. took a long time to get up there. I still remember flying all over New England and New York in the Champ using the whiskey compass and road maps. Get lost go down and read a road sign or town name from the Fire Station. Low and slow is definitely fun.

Posted by: Leo LeBoeuf | November 24, 2010 9:12 PM    Report this comment

I learned to fly in northern Florida. I left the nest with a new (to me) Ercoupe 415 C/D, still a student pilot, and flew my solo cross country from Herlong Field to Robbinsville, NJ. I had maps to find the enroute airports, but I had something a whole lot better for the majority of the flight: the Atlantic Ocean. So long as I kept it off my right wing, I was headed, more or less, in the right direction. I felt like Christopher Columbus and yes, I called my instructor when I arrived.

Posted by: Robin White | November 25, 2010 8:10 AM    Report this comment

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