When “Simpler” Becomes Dumb

I’ve always loved to teach. That love has led me to multiple places within the realm of aviation and aerospace, starting with being the nerdy kid standing in front of his high school government class with his models of Gemini and Apollo spacecraft, to being a NATOPS instructor in the F-14, an astronaut trainer at NASA’s Johnson Space Center for a decade, and a Light Sport Flight Instructor and blogger (writer) today. Through it all, I’ve always strived to make difficult technical subjects accurate and understandable to my audiences.

I’ve also seen and experienced the other end of the scale, i.e., instructors who made technical content more complex that it needed to be in an apparent scheme to demonstrate their mental superiority to students, and instructors who “simplified” the material to the point it became technically inaccurate. Both approaches are a form of arrogance or ignorance; take your pick.

I’m a personal fan of Einstein’s admonition that “everything should be as simple as it can be, but no simpler”. About two weeks ago, I was in Edward Tufte’s class on presenting technical data where he stated that “dumbing down is pandering”. How true! The assumption behind any “dumbing down” is that the audience is not smart enough to understand the technical material but the presenters are. This is often not the case. As a good friend of mine used to say: “You can’t give away what you don’t have”; and that applies to the understanding of a subject as well as other things.

The latest unfortunate example of something dumbed down to the point of being technically incorrect is the current iteration of AOPA’s “Essential Aerodynamics” presentation. Frankly, there is nothing essential at all about it; I do, in fact, steer my students away from it. You know something is dreadfully wrong with their approach when they state that the “wing pushes down on the air”, something that simply does not happen. I say that as an aerospace engineer who, as a student, plotted the pressure distributions about a subsonic wing section in a wind tunnel. Once you see the large low pressure area above the wing which grossly outclasses the high pressure areas underneath, you can intuitively tell that the most accurate explanation for what is happening is that the wing is sucked up from above.

So where did AOPA get the idea that the wing pushes down on the air? I don’t know, but it could have been from someone taught by a teacher who bought into a poorly thought out push by the American Association of Physics Teachers (AAPT) in the early 2000’s to replace Bernoulli’s law, which does a good job explaining how a wing generates lift, with Newton’s laws. The best rebuke to that approach was written and published in their magazine, “The Physics Teacher, Volume 40 in 2002 by aerodynamicist Charles N. Eastlake and entitled “An Aerodynamicist’s View of Lift, Bernoulli, and Newton”. (Ask Google to find it.) In it, he explains how both sets of principles apply and then goes through a technical explanation of the airfoil and how lift is created. He emphasizes that the choice of which set of use depends on which one is simpler to use. Indeed, we did use both approaches (i.e., Bernoulli’s and Newton’s) in various aerodynamic problems to find the answers. But since most kids and many pilots are not going to know how to use calculus, I personally believe that using Bernoulli’s explanation is not only correct but intuitively easier to understand. Additionally, you can use it in a classroom with very simple models (i.e., wing sections and simple wind tunnels) and do the calculations to show the forces involved, something that is difficult to do when using Newton’s laws to calculate the change in momentum of the airflow. When you talk to most people about Newton’s laws, and especially about Newton’s third, they intuitively understand it when talking about the application of thrust, since that’s what we’re nearly all familiar with. But start trying to relate that to the change in momentum of the total airflow field (the Newtonian approach), and they’ll scratch their heads or come up with some off-the-wall and technically incorrect explanation that the wing on a fixed wing aircraft pushes down on the air. Using Newton is a more intuitively easier approach to use and understand when talking about how propellers, jet engines, or rotor blades create force (thrust or lift), even though Bernoulli’s principle is alive and well and at work in them, too.

The AOPA presentation also decides that explaining aerodynamics using a wing is too hard, so they use a surfboard generating “lift” as it races through the water as their example. This is truly baffling, since it ignores one of the major rules of communication (common symbols and experiences between the transmitter and receiver) and totally fails to account for the force of buoyancy, which airplanes other than seaplanes don’t have for long if they land in the water. There simply was no reason for it; it did nothing to simplify the explanations of relative wind or angle of attack and brought the confusing environment of the water in the picture. (Daddy, how come an airplane doesn’t float in the air? My surfboard does.)

The presentation excuses its approach by telling viewers they don’t need to use the common approaches used for a century to explain aerodynamics because they were used for designing airplanes and it only needs to educate pilots (i.e., pilots are not smart enough to understand it). I didn’t think anything of that at first, until I saw where they were going. After that, I felt it was a red flag that it was all about to go off the track. True enough, pilots don’t need to know how to use calculus and integrals or the power and drag required values to calculate what to do next. But they do need to have a proper understanding of how a wing works and that needs to tie intuitively with what’s going on in the cockpit. I can use Bernoulli’s and angle of attack to make it clear what a stall is and that reducing the angle of attack to break the stall is all that counts; I’m not even sure how you could approach it when trying to explain it using Newton’s laws using change of momentum. In fact, I could easily see how someone not grasping it might think you need to use the wing to throw more air at the ground and pull the stick back HARDER. (The same action can result by teaching someone to believe in “impact lift”, which is not lift at all but drag acting in a vertical or near vertical direction.)

I did contact AOPA about this and forwarded them a copy of Eastlake’s article. In response, I got some mealy mouthed excuses about the difficulty of presenting complex technical material. The lesson has remained unchanged. Additionally, a few months after I set my response, “Flight Training” magazine, when promoting this presentation asked its readers “Newton or Bernoulli?”, stepping into the same nonsensical environment the AAPT had created. It’s not an either or choice, except when you’re trying to explain it. To do that correctly, you need to know what you’re talking about. And better care.

There’s a reason why NASA websites and the FAA’s “Handbook of Aeronautical Knowledge” uses Bernoulli for their basic explanation of aerodynamics. Too bad you don’t get WINGS credit for going there; you should.

Return From Missouri (Part 2 of 2)

There was sign next to the self-serve fuel pump I hadn’t seen before. It mentioned a “SUPERUNICOM” operating on the same frequency as the Common Traffic Advisory Frequency (CTAF), 122.8 for this airport. I had never seen or heard of it and, since I was focusing on getting the CT refueled, I didn’t take the time to read it. I fueled up for the next leg, and then met Connie inside the FBO. We sat down to a lunch of peanut butter crackers and Diet Coke while I pulled out the iPad and plotted a new course for our next leg.

Our next fueling stop was to be in Mount Pleasant, Texas. It’s an airfield we typically use as a fuel stop on the trip to Missouri and back from Houston. A single but very nice six thousand foot runway, great facilities, great people, and airplanes from the Commemorative Air Force. To get to it down the west side of the mountains, we still needed just a small jog further west, so I planned to fly southwest to Grove near Lake of the Cherokees before turning almost due south toward Texas.

The winds were strongly out of the southwest when we taxied out for takeoff on runway 19. Three clicks on the CTAF frequency (and not by us) triggered off an automated voice telling us the wind direction and velocity, our SUPERUNICOM at work. Once we were ready, I gunned her up the hill for 19 using no flaps because of the strong, gusty crosswinds, and we hit the top of the gradient about the same time I got to flying speed. We got airborne with a little hop before starting to climb away and turning right almost immediately. I climbed around the scattered clouds at speed driven again more by the oil temperature gauge than anything else. We leveled off a forty-five hundred feet for this leg; the winds were better there, the clouds were below us, and the ride was fairly smooth. To our left, the deck looked fairly solid, the cumulonimbus clouds were still there and quite tall, and I was very glad I had made the decision I did. As we flew over the ridgelines to the south we would have to cross, the clouds looked like they were lower than I had initially thought.

As we motored south past Sallisaw and Fort Smith under the clouds to our east, we saw a regional airliner cross several miles in front of us in a descending left turn. We watched him arc toward the cloud deck and then disappear beneath it as we moved toward skies that were turning milky. The visibility was dropping below us. At first, I thought it was mist; but there was a whiteness to it I couldn’t reconcile. As the puffy clouds moved past us below, one of them was as black as the side of a heavy thunderstorm, even though it was only a hundred feet tall and wide. Then, we were suddenly flying over a wildfire, the source of the white smoke that was filling the sky. There was no one or any equipment down there; it was burning in a solid east-west line. We pressed on south beyond it, and the sky quickly began to clear.

Soon, we were swinging past the snake-like curves of the Red River and entering our home state of Texas. We were still about thirty minutes away from Mount Pleasant, three hours flying time away from home, and a six to seven-hour drive if we were to switch to a car. It was just before two p.m. in the afternoon, the sun was blazing, and the clouds were building, fired up by moisture from the Gulf of Mexico still hundreds of miles away. The visibility was good but not unlimited; there seemed to be some haze in the distance. The cloud bases were moving up but they were also growing vertically; I knew there was a good chance that the next leg of the trip south toward Houston would have to be flown lower, both because of a slight change in heading and because of the building clouds. Both the NEXRAD satellite weather being displayed on our Garmin 496 and the view out the window said there were building cumulonimbus clouds just east of our route; once I got on the ground at Mount Pleasant, I’d take some time to recheck forecasts and take a more leisurely look at them for development and movement. With the long day, we could wait out any convective activity if needed; there was often a two to three hour window late in the day after the thunderstorms had died down when you could fly in, and that was just enough time to get to Houston from there. Since we were flying Light Sport rules, we would have to turn into a pumpkin shortly after sunset; if we couldn’t touch down at Pearland by then, Mount Pleasant would be our stop for the night.

We started picking up KOSA’s AWOS; winds were light and out of the south-southwest, meaning we would be heading for a straight in on runway 17. As we approached, I heard a Bonanza also coming in from the west; but he was much closer so I expected him to be on the ground by the time we got there. I slowly descended the airplane down to about two thousand feet AGL, and we bounced toward the city of Mount Pleasant which we could see through the haze. The confines of the airport and then the black strip of its runway slowly materialized, and I let down to the pattern altitude of 1400 feet to pick up the red and white lights of the 4 light PAPI. They were all white, so I pulled the power back and started slowing down to eighty knots so I could drop to fifteen degree flaps. There was just a little bit of gustiness in the winds, so I slowed down to sixty knots instead of a calm wind fifty-four and flew the glide slope on the PAPI using power until I made the runway and I touched her down.

Turning right onto taxiway Charlie, I called clear of the runway over the radio and headed us toward the FBO and the self-serve gas pumps to the north side. Pulling up to the pump, I went through the Shutdown checklist, pinning the BRS to keep it from being inadvertently fired, shutting down my electronics and then the engine before pulling the circuit breakers that act as a Master switch. We opened the doors and slid out, and Connie headed toward the FBO while I got out and headed to the pumps to get us gassed up before taking my break.


Unlike the day before when a low pressure system in the Gulf had pumped lines of thunderstorms up from the south, the cells I was seeing on the radar today seemed to be moving very little and the coverage was isolated to small pockets we could fly around if needed. The forecasts were calling for a chance of thunderstorms until six p.m., but our route (for the moment) was clear. As Connie and I took another Coke and Cracker break, I told her it looked good for pressing on. We had the option of stopping for the night at Nacodoches if Houston got socked in; there was bed and breakfast there I was interested in checking out if the need arose. So, after getting refreshed and briefed, we climbed back into the CT and taook off to the south.

The cloud bases were at about forty-five but the tops were up at about eight thousand and rising in the fiery sun, so I leveled off at thirty-five where it was about eighty degrees and infected with a bumpy ride. Turbulence usually forces me to hand fly the airplane especially with Connie aboard; I do a better job smoothing out the bumps than my simple autopilot which has no filters and climbs and dives like a Kamikaze in them. We flew south past Longview, Nacodoches, and Lufkin before driving just east of the large Class B ring surrounding Houston, watching the rain from numerous cells fall in misty sheets just east of us. I held our altitude until we were approaching the east side of Galveston Bay, before letting down to 2500 and finally 1500 feet to scoot under the floors of Houston’s Class B. Hugging the coastline on the north to give us some option other than ditching if we suffered an engine out, we made our way past La Porte and the restaurants at Kemah before turning west just south of Clear Lake. The familiar haunts of Johnson Space Center and Webster slid down our right side; we could see the large expanse of runways that are Ellington Field just beyond. I dialed in Pearland airport’s ASOS; the winds were favoring runway 14. We entered the pattern on a forty-five from the southeast, put the flaps down at fifteen on the downwind abeam, and landed, glad to be home.

Return From Missouri (Part 1 of 2)

It’s been a tough summer for us. Connie, my wife, discovered she had a serious medical condition and, in the middle of us dealing with that, her mother, who had been suffering from failing health, died. Her dad, a Marine World war II veteran and 95 years old, was still adjusting to the loss of his only partner (as we all were), and Connie felt she both wanted and needed to spend some more time with him. The thought of driving that trip was too much for me; so we decided to fly the CTSW up over Labor Day weekend, when I had an extra day off. The weather for the trip looked pretty good for the trip up from Houston and it was; while it was too rough a ride for Connie down low, the bases of the scattered cumulus clouds were around five thousand, so I took us to 6500 feet where we found light headwinds and a smooth ride. We flew from Houston to Mt Pleasant, Texas (one of the most hospitable airports anywhere; I left my billfold there once and the airport manager flew it down to Conroe where I retrieved it with nothing lost.), and then on to Rogers at Bentonville Arkansas and finally to Kirksville, Missouri where we bedded the airplane down. We had originally scheduled our return for Labor Day; but we had known when we left that the weather might be problematic for a return. I got up early and started checking weather. The Terminal forecasts for Houston hobby were talking about thunderstorm activity but Convective SIGMET issuances were expected. The National Weather Service forecasts were talking about a system in the Gulf pumping bands of moisture up from the south…. thunderstorms and locally heavy rain were possible with the chance of rain was about 60%. It was still forecasted to be VFR outside the TRW activity, but when you see those kinds of rain chances in Houston you have to be concerned about whether you can work your way around even with a VFR forecast. The storms often move in bands south to north; and, if you’re coming down from the north, you’ll be forced to make her large deviations or divert to avoid them. I was certain from the forecasts we could get to Mount Pleasant before we ran into anything and maybe Nacogdoches if we were lucky, but I told Connie the odds were good we would have to spend the night north of Houston and scoot in the next morning. She didn’t want to “stage” an arrival; and, since our whole point in making the trip was to give her the most time possible with her dad, I made the decision to delay a day when the forecasts looked better.

“Better” does not mean perfect. No matter which day we went home, winds were going to be a big issue through Missouri. On the surface they were out of the south to southwest at sixteen gusting to 24, forecasted to be one knot below the recommended operating limit on the surface for the CT. (I had operated the CT in winds up to about 22 kt gusts, and the airplane buffeted around on the ground but was very manageable at zero or negative six flap settings.) Crosswinds were not going to be a big problem, but headwinds were and I was concerned turbulence might be. At three thousand, winds were forecasted to be out of the southwest at thirty knots plus, which would take a big chunk out of the CT’s 112 knot no-wind cruise speed. The winds actually got better as you went higher; forecasted winds at 6500 were down to 25 knots or so. That made the big question: could we get there or would the cloud decks force us below? Sometimes, the Gods of Class E airspace and Light Sport rules would force you to descend because the cumulus clouds would be building so high it was not possible or practical to go over them. So, down you’d go to maintain adequate ground contact…even with a perfectly functioning moving map GPS…into a turbulent ride. All we could do was get going and see where it led.

We took off from Kirksville’s runway one eight at about eight-thirty in the morning. The winds were blowing almost straight down the runway at ten knots, so we got off fast and were climbing right away into wind getting higher fast. By the time I was climbing through three thousand feet, the GPS groundspeed was showing only 25 knots, a number I had never seen before on my GPS even when playing with slow flight in a headwind. (Best rate…which I was climbing at…was 78.) I kept her climbing, using a cruise climb set more by my engine oil temperature than anything on the airspeed indicator. We slowly made our way up to 6500 feet, where I nosed her over, popped the flaps into their minus six degree, full-up position, and let the engine accelerate us to cruise. Our ground speed clocked up to 87 knots, exactly the 25 knot headwind component we were expecting. Thankfully, the ride was smooth, so I clicked on the autopilot and let it track the course in our GPS while I followed our progress on my iPad, tracking my emergency landing fields as we flew past them. Even when we were out of range of any, we were still in good shape; below; the green farm fields were flat and separated by crisscrossing, long dirt and paved roads, any of which would do to land the small CT on if her engine croaked.

We steered southwest, turning south just to the west of the huge expanse that was Whiteman AFB some ten miles or so away. We picked up some knots with the turn; our groundspeed climbing up to 93 knots. We were now running a few knots ahead of the flight plan, making me feel a little better about not having any problems getting there. Until I used XM satellite weather to pull down the latest METAR. Our destination was the Class D airfield at Rogers, Arkansas, the home of the Walmart FBO. The METAR reported the field was broken at 2700 feet, eight hundred feet lower than the forecast had predicted. While that was plenty for us to get in, it was below the three thousand feet I use for flight through that area. Rogers is at the north end of a mountain bowl full of airfields that included North Arkansas Regional, Springdale, Fayetteville, and Fort Smith. To get out, we had to cross a ridgeline south of Fort Smith that jutted up to 2700 feet MSL, leaving us 1400 feet to go over it. While that was workable, it was not desirable, and the winds over it would more than likely make it a jolting ride.

As we approached Monnet, Misssouri, I could see the broken layer ahead, an ever thickening lake of cumulus clouds only three or four hundred feet thick. It went as far south as I could see, completely covering the mountains I knew we were approaching. What really got my attention was a cluster of towering cumulonimbus clouds slightly off to the east, signaling to me that possible rain and even thunderstorm development that could happen here could be an issue. I was very concerned that the ceiling and developing weather could keep us trapped in the valley for the afternoon, delaying us to the point of not making it to Houston today. I started looking at the iPad, which had our current position displayed on a sectional, for possible divert fields. Joplin was the closest and had the best facilities, but I wanted something both further south and east to reduce fuel consumption on the next leg and give us some room to scoot down the mountain range on the east side. I checked the information for Neosho; it was in a better location and had a city run FBO with self-service 100 low lead. At that exact moment, my wife, seeing the same things out the window that was concerning me, said something about a divert. Disengaging the autopilot, I pointed the airplane at Neosho and told her we were headed there, rather than heading into an area where I had doubts that we could proceed on when we wanted.

We tracked past Joplin and as we approached Neosho, I throttled back a bit to begin a descent. The ride roughened considerably as we descended past Granby, angling toward Neosho and the single north/south runway of its airport beyond. I dropped us down to about two thousand feet, scooting beneath the dotted clouds, as I angled us right to align with the runway for a very long straight-in. Connie spotted an aircraft on our right side and low; it took me a minute to find it, thought it was a twin at first but realized it was a crop duster as I got a better look. He seemed to be slowly angling away from us even further right; I saw him turn across a highway and seemingly head toward a field I assumed he was going to work, so I told Connie to keep him in sight and let me know if he headed our way. I continued toward the runway looking for other traffic and making a couple of radio calls marking our position and our intentions, when Connie let me know he had turned and was headed toward the same runway we were. I picked him up and, sure enough, he seemed to be flying a lot faster and was bee-lining toward the approach end of the runway, seeming oblivious to our presence and the radio calls I was making.

We were approaching runway one-nine with a lot of turbulence and a gusty, ten knot crosswind. The crop duster was about a half mile in front of us, touching down on a slanted runway that looked like it was running up a cliff before folding over and running flat, hiding its far end. Connie thought we needed to wave it off, that the crop duster was going to turn around and back taxi, but I told her I was continuing, confident there was a turn off at the end of the runway if not before. The airplane did turn off before getting to the end, just as I touched down a little past the first third of the runway and about half way up the climbing hill.

We turned left just north of the FBO, taxiing toward the gas pump we could see and past the crop duster and its pilot, who was exiting the airplane. I shut the CT’s engine down, and we opened the airplane’s gull wing doors to the hot air the gusty wind was circulating.

“Hot as hell, isn’t it?” the crop duster pilot said, walking past us and wiping his brow.

“It sure is,” I agreed. Meanwhile, Connie exited the airplane to head for the FBO, its air conditioning, its vending machines, and its bathroom.