In Germany, where I live, the term Langzeitstudent or “longtime student,” refers to a student who takes way too long to finish their studies, take the exam, and finally stop living on the money of others—like parents, grants, or public funding for students paid by hard-working people’s taxes. And while I finished my academic studies many years ago, I guess you could still call me longtime student, at least when it comes to learning flying. I properly started my German ultralight training in 2018, passed the theoretical exam in 2019, have enough flight hours to go on to the practical exam—but I am still not done, because I did not feel ready so far.
That’s because interruptions force me to catch up with myself when I start again. Like every proper longtime student, I can name lots of external reasons for the delays: it started with my initial fear of flying and the first fifteen hours or so I had to use to overcome this fear (see my Air Facts article a few years ago). Later, job-related time constraints delayed my training several times. Finally, the coronavirus pandemic caused the flight school to close for several months and also imposed some funding issues on me. I am even at the point now where I have to repeat the theoretical exam, because it is more than three years since I passed it. However, whenever I go back to the cockpit, I feel right at home. I could compare it with riding a bicycle, which you also won’t forget, but I am also convinced that flight simulation on desktop computers helped me to keep in a mental state of preparedness.
In this article I want to point out in which aspects flight simulation helps me when I can’t take real flight lessons, but I also want to mention a few problems which arise when you are just in front of a desk instead of being in the real cockpit.
Desktop flight simulation
The visuals on modern desktop simulators are almost indistinguishable from the real world, but that doesn’t mean the physics are real.
Flight simulation on desktop computers at home is not to be confused with certified training devices. Even though software developers like to say their products may be used in FAA-approved training devices, the software itself is just a part of said devices, and any certification refers to a special hardware and software combination. Microsoft Flight Simulator, X-Plane 11, or AeroflyFS 2 are always on the thin edge between video game and serious simulation, and if in doubt they lean more towards the gamey side of the user spectrum. Even Prepar3D, which is marketed to students and professionals and not available to gamers, is still based on old Microsoft Flight Simulator code.
The aircraft which come with such simulators are often visually impressive, but usually dumbed-down, to reduce development costs and make the planes more enjoyable to inexperienced gamers. Performance values are off, flight conditions like stall, slip, or spin are not properly simulated, and aircraft systems are simplified. The good thing, though, is that many flaws are fixed by flight simulation enthusiasts. These people often consist of real-world pilots, who either use simulators in parallel with their real flying, or who did fly in the past but stopped due to health or financial reasons. In addition, there exist commercial developers who try to simulate certain properties of a specific aircraft type as detailed as possible within the constraints of a desktop setup. Such developers often have flight experience in the simulated plane and often it is their honest love for the aircraft that makes them simulate it. And these kinds of models can indeed help you in the times of grounding.
Helping to stay in a mental state of flying
The biggest use desktop flight simulation has for me is to “keep in touch” with the aircraft even when I can’t use it in the real world—in terms of cockpit layout, instruments, and procedures. This works especially if you approach the simulator not as game, but fly as seriously as you would do in the real world, in a planned and structured manner.
Before I had access to a simulated model of my real world aircraft, whenever I returned to the cockpit after a break of some weeks or even months, I had to get used to it again. Sure, the Comco-Ikarus C42 ultralight is not a very complex aircraft and there was the checklist, but more than once I forgot stuff when I returned after being absent for a longer time—little things like switching the fuel pump off before magneto check and switching it on again afterwards, switching off the engine while the avionics were still running, or not using carburetor heat in cold and humid air. Nothing bad happened (except one time the engine had a little hiccup because I forgot the carb heat), but it was still wrong and could have had negative consequences. Or take my confusion about the correct power setting in downwind I had once: “why are we sinking?” I asked my flight instructor, and with his calm and dry manner he just pointed to the RPM gauge. Well, I had better get familiarized with the plane again before that flight lesson…
With a few add-ons, you can usually fly the same model airplane in the simulator that you fly in real life.
I am really not sure why I made these mistakes back then, because the checklist in my hands clearly told me what to do, but there was some disconnect between reading the checklist and executing the steps. Nowadays I am convinced that it was the faded “muscle memory;” if you don’t practice, you forget it, and if you don’t have time or funds to practice enough, well… maybe consider postponing your flight training to a period in your life when you do?
At least that was what I thought back then.
But then I got the chance to help with the creation of a simulated model of the C42 for the X-Plane simulator. I took photos, made measurements, made test flights, and helped an audio engineer with recording aircraft sounds. In the end I had a simulation of “my” aircraft. I made sure that the instruments, the panel layout, the bicycle-like flaps lever above your head—even the pre-flight check—was re-created in a nearly realistic way, and that the flight dynamics were made plausible enough to help me with my training. Other developers have created other aircraft in a similar manner, and for many well-known general aviation planes you can buy a proper simulation model nowadays, as add-on to the simulator.
Whenever I cannot fly in the real world, I fly at least with “my” simulated plane. I make sure that I use the real-world checklist in the calm environment of my home, reading aloud each step and performing each step in the simulation, having visual, audible, and performance feedback. The simulated airplane does not induce the same feel as the real one (well, no feel at all, because my desktop chair does not move), but it assures me on my interaction with the plane. This is somewhat similar to the “mental” flying from the armchair, where you visualize certain situations and procedures, but the difference is that you actually do the steps. I noticed that this helps me tremendously to keep in the mental loop.
Planning and navigation practice
One area in which desktop flight simulations really shine is the possibility to practice navigation procedures. By this I don’t mean preparing an actual flight you want to conduct afterwards, but to understand and practice the typical steps of planning. So even though the navigational data in the simulator may be outdated or incomplete, or even though not every real-world landmark may exist in the simulator, you can still learn how to navigate by streets, railroad tracks, power lines, lakes, rivers, forests and towns. You can learn to read sectionals and approach plates.
The instruments are realistic enough that you can practice navigation and approaches.
You can practice VOR navigation, GPS usage, ILS, and RNAV approaches. You can get accustomed to coping with airspace structures in huge urban areas, like San Francisco or Berlin. And if you fly online, you can even do this with actual human air traffic control, which sometimes may be even more strict and less forgiving than their real-world counterpart. All of this creates a learning environment which is not only a great addition to theory classes, but an easy way to practice seldom-used procedures every once in a while, even if not flying during that time.
Negative effects of desktop flight simulation
Despite the mentioned advantages, one should always be aware that, as realistic a modern simulation may look like, it is still just an entertainment product which was not created to be a learning tool. Even the most detailed airplane models for simulations, which sometimes can be more expensive than the simulation software itself, can have errors or misbehaviors in comparison to the real airplane.
Other differences are rooted in the simulation environment, especially the controls. Even if you use a high-quality joystick or yoke, rudder pedals, and separate throttle, the movements you make with these controls and the feeling of moving them, without actual feedback, differ a lot from the real aircraft. You can move typical desktop controls only over a very small range, so even small movements of a stick, throttle lever, or pedal can yield strong effects in the simulated airplane. Even if you calibrated the controls as carefully as possible, you will never have the fine control of “pitch and power” or the rudder as you have in the real aircraft. As a bad consequence, arising from your goal to make the simulated plane behave as you want it to, you may get a bit “shy” in moving the controls or develop a tendency for over-correction.
I noticed this problem after I was simulating a lot and then returning to the real cockpit. In my first two or three traffic patterns after returning, I had to adjust to the movement range of both the real throttle lever and real stick, and to un-learn the tiny movements I used in the simulator. This proved especially critical when making rudder inputs in turns, and while flaring during landing. In the real C42, the stick is in the center console (so just one stick for both crew members) and you can pull it backwards really far. You pull it not just with your hand, you also use your upper arm muscles for holding the stick in the pulled position. On the desktop, that requires much less effort and you must be aware of that once you get back to the real aircraft again.
We are in the second year of the COVID pandemic already and at least in Germany there is a slight hope that the locked-down lives can become more normal soon, at least in the summer. This will allow me to go flying again. Just today I planned the next months with my flight instructor, so I can hopefully make the practical exam in a foreseeable time. A few years ago, I would have felt as if I need to re-learn everything after such a long break, but thanks to some structured simulator sessions, I know at least my way around the plane, the cockpit, my typical flying area, and basic maneuvers. Despite the negatives, the simulator sessions still give me confidence and a certain calmness, which will also help me with my real flying.
Mario Donick was born 1981 in northern Germany, near the Baltic Sea, and now has a PhD in communication studies. For many years, he was only using flight simulations, about which Mario also writes reviews, tutorials and manuals for FS MAGAZIN (German bi-monthly print magazine). He does freelance work for simulation add-on developers, supports customers in this field, and provides independent research on the perception of simulations and games, currently mainly related to virtual reality and flight simulation. His real aviation career started in 2017, when he finally – despite his fear of flying – decided to go for an ultralight license.
Now that the Garmin Autonomi has been developed and certified the question of how much flying an autopilot can do has been answered. Everything. The Autonomi can autonomously select an appropriate airport, fly the approach, and land the airplane without human intervention or input.
The Autonomi system is intended for emergency use only, but it is the premier example of how capable automatic flight guidance systems can be. Even without autonomous landing capability, the modern autopilot can fly with incredible precision in all phases of flight. And over all but brief periods, the capable autopilot system will be more precise and smoother than the human pilot.
Garmin’s autoland technology is just the most visible proof that modern autopilots can do it all.
However, without redundant fail-operative systems, the human pilot must hand fly at least some of the time. How does the human pilot retain and practice the skills necessary for precision hand flying while still making best use of the autopilot system? That’s the question.
In single-pilot high performance airplane flying, the standard procedures and training are for the autopilot to fly nearly all of every flight. It’s required that the autopilot system be fully functioning on every single-pilot flight in jets, and on charter flights flown by a lone pilot. And you won’t get past a checkride at any major training facility as a single pilot without using the autopilot in all phases of flight and fully understanding all of its modes and capabilities.
There is historical precedence for autopilot use by a single pilot. When I first started flying jets 40 years ago, the standard procedure was for the pilot flying—the one actually manipulating the controls—to do nothing but scan the instruments and move the controls. If the pilot flying (PF) wanted to look at a chart, tune a radio, review a checklist, or do anything else except look at the flight instruments he handed the airplane to the other pilot.
It was a small step from the concept of the PF doing nothing but holding heading and altitude, the proper airspeed and course to having an autopilot do the same thing when there was no qualified human pilot in the other seat.
It makes sense to me that pilots flying IFR in piston airplanes would benefit from applying the same procedures. By using the autopilot to its fullest capability, the human is freed from the need to concentrate essentially 100% of his attention on maintaining the desired flight path.
Of course, the human must continuously monitor the autopilot actions and performance. But that’s much easier than hand flying full time. You have experienced this anytime you’re flying in the right seat—or sitting in the passenger seat of a car. It’s so much easier to see “what the other guy is doing wrong” from that position than when you’re the one with hands on the controls.
It’s also accepted practice that the autopilot fly approaches with weather near minimums. In fact, reduced minimum category approaches are based on use of automatic flight guidance. And autopilot flight is also a part of approval to cruise in the reduced vertical separation minimum (RVSM) airspace above Flight Level 290. Regulators recognized that when you’re descending to within 100 feet of the runway (or less on an ILS) or maintaining cruise altitude in the thin air above FL 290, only automatic systems have the consistent precision of performance.
But none of this addresses the fundamental question of how we human pilots keep our flying skills—particularly our instrument scan—polished while the autopilot does nearly all of the flying. One answer for pilots of jets is the FAR 61.58 requirement to be trained and checked annually. During that recurrent training you will be expected to use the autopilot fully, but you will also experience autopilot failures in the simulator, typically during critical, high workload phases of flight. If you demonstrate proficiency during those events your skills are up to date.
Jet pilots have to regularly check their scan in simulators, but what about light airplane pilots?
For pilots flying airplanes that don’t require a type rating, there is no FAR 61.58 to check our skills. The flight review every two years is only a review, not a check. And the review can be flown in any class of aircraft you’re rated for, not the most demanding. And it need not be flown under IFR standards even if you’re IFR rated. The flight review is better than nothing, but will only be as beneficial and revealing as the pilot and CFI want to make it.
Many pilots, including me, opt to hand fly much of the departure and climb to cruise. This is a higher workload phase of flight, often with configuration changes, intermediate level-offs, vectors, course changes, and speed adjustments. It’s a pretty good workout of your instrument scan and control precision.
But when the air is choppy and the ATC instructions are changing fast, I look at the instruments and wonder if I’m giving the passengers the best possible ride by hand flying. No matter how hard we concentrate and try to be smooth on the controls, none of us can match the performance of a modern, sophisticated automatic flight guidance system.
One reason is that the autopilot never scans. Dedicated channels continuously track each flight parameter, something our best scan simply can’t do. The word “scan” gives it away. The autopilot never scans because it is 100% dedicated to the task.
Modern autopilots also have very sensitive anticipatory capability. For example, when approaching an altitude capture the system obviously monitors altitude and vertical speed as we humans would. But it also has accelerometers and uses that information to calculate an intercept and level-off limited to no more than a few hundreds of a G, while never over- or under-shooting target altitude. Maybe I get lucky and match the autopilot smoothness sometimes, but it does it every time.
We’re watching these same questions and concerns play out on a very big stage with introduction of autonomous control of automobiles. How to keep the driver involved and in command while also reaping the benefits of automatic control are the burning questions. Sound familiar?
My hope is that with millions of participants in the move toward autonomous driving vehicles instead of the few hundred thousand of us pilots, we will learn more about human interaction and control of automatic guidance systems and all benefit.
Until that happens we’re each as pilots left with the question of how much hand flying practice do we need to be safe and competent while still fully using the safety and comfort capability of the automatic system. After all of these years of flying, I’m still not sure that I know for myself, much less deliver an answer for other pilots.
When people ask Mac McClellan what he does for a living, he replies, “I fly airplanes and write about them. And I’m one of the most fortunate people in the world to have been able to make a career of doing what I love.” Mac has been a pilot for more than 45 years, an aviation writer for more than 40 and has been lucky enough to get to fly just about every type of personal and business airplane in production from the 1970s onward. He was on the Flying Magazine staff for 35 years and editor-in-chief for 20 of those years. He has private pilot privileges in single-engine airplanes, commercial pilot in helicopters and ATP in airplanes with more than one engine. He holds several business jet type ratings and has logged more than 10,000 hours. His first airplane was a Cessna 140 and for the past 27 years he has owned a Baron 58 flying it more than 5,000 hours to cover the aviation industry. And now he is a part-time corporate pilot flying a King Air 350.
Density altitude. We cannot see, smell, or taste it. However, it is something that must not be ignored. There was an incident in which four people died because they failed to account for density altitude: three Marine Corps helicopter pilots went up to a high altitude airport to pick up a passenger with their baggage, and, on a hot day, took off and tragically never got out of ground effect.
Density altitude is the measure of air density relative to a standard day. A standard day is barometric pressure of 29.92 inches of mercury (in Hg) and sea level air temperature of 15°C (59°F). Density altitude is pressure altitude corrected for non-standard temperature, so pressure and density altitude are the same in standard day conditions. As the temperature rises above standard and altitude increases, the density of the air decreases, resulting in an increase in density altitude. The important part about pressure altitude is that the aircraft performance data under non‑standard conditions is obtained using pressure altitude.
Density altitude is how the airplane thinks it is performing and is not meaningful when considering height above any given point.
Your “book numbers” are going to be wrong when it’s this hot.
The standard datum plane, which by international agreement is considered to be representative of the atmosphere for pressure altimeter calibrations and other purposes, is a level where the atmospheric weight is 29.92 in Hg on the barometer. As atmospheric changes occur, the datum plane changes to either above or below sea level. Pressure altitude is obtained by setting the altimeter to 29.92 in Hg. Then the altimeter will indicate altitude in feet above the standard datum plane or the height the aircraft is above the actual pressure of 29.92 in Hg. This, however, would not necessarily be the distance above MSL. It would be the height above the imaginary plane, which would be displayed as either above, at, or below mean sea level. Pressure altitude can also be seen as the height the aircraft would be if the actual atmospheric pressure at sea level were 29.92 in Hg.
Another way of determining pressure altitude is to subtract the altimeter setting from standard barometric pressure, 29.92 in Hg. Take the difference and, referring to Table 1 below, convert altitude to feet. Add this to the field elevation or altitude at which you are flying, and this will result in pressure altitude. As a refresher, barometric scale on the altimeter is calibrated from 28.00″ to 31.00″ and is read in inches Hg. Each increment on the barometric scale represents ten feet.
Along with the different types of densities come different types of altitudes and temperatures. The chief components, in the order that they affect density altitude, are pressure, temperature, and dew point. These variables are directly affected by the weather. When one or more of these variables varies, the density altitude varies. To take this one step further, density altitude can occur at any location regardless of the altitude, time, or weather conditions. If the barometric pressure decreases, and the temperature and dew point increase, so does the density altitude.
In this configuration, the density altitude could possibly be, for example 5000 feet, while the airport field elevation is actually at sea level. Now imagine being at an airport where the field elevation is 5000 feet, then add another 5000 feet for density altitude. The aircraft would be performing at 10,000 feet. I have personally experienced density altitude at sea level which is illustrated by bad aircraft performance. As I broke ground at Catalina Island one day, the stall warning horn went off.
Density altitude directly affects the aircraft’s performance. Using standard barometric altimeter of 29.92 in Hg as a datum, a high barometric setting, and include a high or low air temperature and dew point, then the density altitude is less. On the other side of the datum, with a low barometric pressure, high or low air temperature and dew point, the density altitude is higher. A high barometric setting means low density altitude; a low barometric setting means high density altitude. A combination of increasing the physical altitude and temperatures at the same time dramatically increases the density altitude.
The engine and airfoils of the aircraft rely on air density for performance. Warm air molecules expand, resulting in fewer molecules of air, which makes the air thin.
Flying forces the thin air over the airfoils, resulting in either a minimal to a significant effect in reducing the aircraft performance. There is a reduction in lift and drag when the air is thin with an increase in density altitude. The takeoff, rate of climb, distance to climb, fuel, time, service ceilings, and landing performance are reduced by the effects of density altitude.
The most vulnerable segment of flying affected by density altitude is the takeoff and climb phase. Density altitude should also be taken into consideration in the landing phase. Use the normal indicated airspeed on the approach, because of higher true airspeed. Anticipate a higher ground speed and longer landing roll after touchdown.
As you fly into warmer air, the engine has less air to burn so there is less power. Engines consume air by weight and at lower density, the same volume of air will have less weight. With less mass (weight) of air available due to lower density, the engine produces less power. In ideal conditions, combustion of the ratio of fuel-to-air mixture is constant, so when the mass of air available for burning in the engine drops, so does the fuel flow. Engine horsepower decreases because the engine takes in less air to support combustion. The propeller efficiency (thrust) is reduced because it exerts less force at higher density altitudes versus lower density altitudes. In other words, the air is thin and there is less air for the propeller to grip. Turbochargers only help the engine think it is at sea level, which increases the amount of air entering the engine to generate more horsepower. However, turbochargers do nothing for the propeller or airfoils.
What does all this mean in the real world, and when should density altitude be taken into consideration? First, let’s perform a comparative analysis using the Cessna 172 POH, and different altitudes like sea level and 8000 feet using percentages in performance change. Remember, this is according to the book. By looking at the results, density altitude should always be taken into consideration when flying. Here is a comparative analysis from a 1979 Cessna 172N POH for data on performance:
Sea Level, 15°C
8000 Ft, 15°C
(Max Wt Short Field)
56KIAS / 805ft
N/C KIAS / 1740ft
(Max Wt Short Field)
60KIAS / 520ft
N/C KIAS / 700ft
Max. Rate of Climb
73KIAS / 770 FPM
69KIAS / 349 FPM
Max Rate of Climb for:
116KTAS / 8.4GPH
122KTAS / 8.4GPH
Range (40 Gal Tanks)
472 nm / 114 KTAS
485nm / 122KTAS
Endurance (40 Gal Tanks)
To summarize the comparative analysis example above: takeoff distance increases by 54% and landing distance increases by 26% when altitude and temperature change. Maximum rate of climb has a decrease in airspeed of 5%, and feet per min climb a decrease of 55%. Naturally there is a decrease in maximum rate of climb for time, fuel, and distance because sea level is sea level and climbing to 8000 feet naturally takes more effort to reach altitude. Cruise performance increases 5% in airspeed at the same fuel consumption. Range performance increases 5% in distance and 7% in airspeed. There is no change in endurance.
So what does this really buy you? One: Be extremely careful on takeoffs and landings, and be exceedingly patient climbing to altitude. Two: There is a gain of six KTAS at the same fuel consumption in cruise performance, or 13nm and seven KTAS in range performance. For example, the cost of a $100 per hour aircraft remains constant but the hours decrease with altitude at the same fuel consumption. In terms of dollars, in order to save $10 in range, $30 will be used in order to reach altitude.
To move to our next phase, let’s solve for density altitude. Our iPads, glass cockpits, and weather reports from ASOS give us density altitude. Nonetheless, if you find yourself one day on some remote landing field without any of this information, don’t panic. There is always the good old fashioned way of solving for density altitude. We do not need a calculator, computer, slide ruler, or an abacus. All we need is today’s modern miracle, a Post-It, and a workable number two pencil. Put them together with some pre-Civil War mathematical knowledge. Here is an example.
Station Pressure = 28.80 in Hg
Field elevation = 8000 feet MSL
Surface temperature = 30°C (86°F)
Pressure altitude at field elevation = ((29.92 – 28.80) x 1000) + 8000 ft = 9120 ft
The standard temperature for 9120 feet from Table 2 = -2.831°C
Variation of temperature = 30°C – (-2.831°C) = 32.831°C
Density altitude = 9120 + (120 x 32.831) = 13059.72 feet or 13,100 feet
Let me add some details. Variation of temperature is the variation of the actual temperature from standard temperature at the pressure altitude. The 120 is the approximate change in density altitude per 1°C, variation from standard temperature. Or, you can solve the whole problem by referring to Table 3 after solving for pressure altitude and variation of temperature, and obtain density altitude.
As friendly reminder during those hot summers days, check the aircraft POH performance charts before venturing out. Performance charts can be in either density altitude or pressure altitude. Also, take into consideration the following: age of the aircraft, condition of the runway (whether it is a grass strip, sod, wet or soft, rough field, dirt, gravel), and distance relative to the mountains.
If you run into an atmospheric condition under which the aircraft cannot fully perform, then instead of taking the risk, do not fly or stay at a lower altitude where the aircraft can reasonably perform. Go flying early or late in the day. There always plan B: go swimming, drink a nice cold Frappuccino from Starbucks, both, or whatever it may be, but it is better to be safe than sorry.
Norm Ellis has is an instrument-rated private pilot, has flown twenty-five different aircraft, and is a retired Aerospace Mechanical Design Engineer. He holds three multi-STCs certified on 118 aircraft.
It was one of those early spring days when the lows were very low, the high pressures very high, and in between the wind was howling. As is often the case on these days, the sky was clear and the flying conditions good—until it was time to land.
I was waiting my turn to go on runway 16 at Chicago Executive—the place many of we old timers still call Palwaukee—and the wind was blowing from 250 degrees at 22 knots, with gusts to 32 knots. In other words, it was exactly a direct crosswind. Ninety degrees to runway 16-34, the main runway, and the only runway realistically usable by turbine airplanes.
Pilots of the piston airplanes were wisely waiting out the blow so I got to watch a parade of bizjet pilots tackle the crosswind velocity that was near or above the demonstrated—but must always add not limiting—capability of their airplanes.
Each pilot was carrying a huge crab into the wind down final approach. And the air was bouncy, so wings were dipping up and down. And no doubt the indicated airspeed was bouncing around. Reports of gains and losses of five to 10 knots airspeed on final were common.
As each pilot descended close to the pavement they attempted a de-crab maneuver by lowering the upwind wing, or in some instances simply ruddering the nose away from the wind with the wings more or less level.
Tires smoked at touchdown, and the airplane noses jerked back toward the centerline. Despite a crosswind at the limits, nobody that I watched came close to having serious control problems after touchdown.
We’ve all seen this movie before on countless videos of airline pilots attempting to land in extreme crosswinds. Sometimes the wind wins and the crew goes around when they can’t stop the drift. But more often than not, the amateur videographer captures the jet touching down in a significant crab angle to the runway, tires smoking, and the airplane nose pivoting back toward the runway centerline.
How is it possible to land in such extreme conditions? There are several factors that matter, but the most important is that the pilots are holding a track over the ground that aligns with the runway centerline. It’s not where the airplane is pointed but where it is going, where the mass of the machine is traveling, that allows it to remain on the runway after touchdown.
In little airplanes we are taught that in crosswind landings using the aileron and rudder to align the nose of the airplane with the runway centerline is essential. And if conditions allow that, it’s an excellent and predictable landing technique.
But when the breeze is up, keeping the nose pointed exactly at the far end of the runway can be difficult—and at some wind velocity, impossible—and the airplane will slide downwind. And when that happens, it’s pretty much game over for a predictable landing because the airplane will touch moving sideways which means its mass, its energy, will be heading off the runway instead of down the runway.
The essential technique is to keep the airplane tracking over the centerline, even when that requires a crab into the wind. If the airplane track is true to the centerline, the inevitable swerving after touchdown can be controllable because the momentum of the airplane is down the centerline.
With tricycle landing gear the center of mass of the airplane is ahead of the main gear. That means when the airplane touches in a crab the momentum will pull the airplane back toward its direction of travel. Its ground track, in other words. If that track had been down the centerline, the momentum wants to continue down that path.
Of course, once the airplane is on its wheels the crosswind isn’t done with its evil efforts. The airplane is really a weathervane so the wind is going to push the tail away from the wind direction. Opposite rudder is the solution, but rudder authority is limited, especially as the airspeed slows. That leaves nosewheel traction and some differential braking as the tools to keep the airplane tracking straight on the rollout.
Jets have several distinct advantages over piston airplanes in this regard. For one, jets sit on their gear at a negative angle of attack so when the nose comes down the lift is gone and the tires—most importantly the nosewheel—can grab the pavement. Light airplanes sit on their gear at a very neutral angle of attack, or perhaps even a little positive (nose up) in some models. That means the wing still is producing some lift after touchdown, robbing the tires of needed traction for control.
Another great crosswind landing advantage in jets are spoilers. When the airplane touches, the spoilers pop out, killing nearly all lift and planting the airplane on its gear. In light airplanes it’s easy to bounce, at least a little, and that requires yet another fight for control to keep the airplane tracking down the centerline.
And the wing loading in jets is many times higher than in a piston airplane. That means gusts of the same strength simply can’t displace the heavier airplane as much, no matter how good or quick a light airplane pilot is on the controls.
If you’re flying a taildragger, forget everything above. Taildraggers really need to touch down with the longitudinal axis aligned with the centerline and not in a crab. The reason is the center of mass is located aft of the main gear in a taildragger, so the momentum after touching in a crab will try to carry the tail beyond the nose. A ground loop, in other words.
So for those of us flying nosedraggers on windy days, remember it’s tracking the centerline that matters most. If you maintain that track the touchdown and rollout can be a thrill, but you and your airplane can handle more crosswind that you may expect.
Four decades ago, I learned to fly in a Piper Tomahawk at Fairbanks, Alaska. Since then, through job changes, multiple moves, raising kids, lots of distractions, and eventually retirement, I wanted to go back and really explore the far north by air. So I determined to fly from my home in Charlotte, North Carolina, to the limits of arctic Alaska, then return, flying across northern Canada, finally returning to Charlotte.
My route took me to the westernmost and northernmost airfields on the North American continent—at Wales and Utqiagvik (formerly known as Barrow), in Alaska. I also visited Anchorage, Nome, Kotzebue, and Fairbanks in Alaska, and Whitehorse, Inuvik, Yellowknife, and Churchill, as I crossed northern Canada. Overall, the trip totaled over 9000 nautical miles, across some of the most remote and beautiful terrain in the world. Many of the places I saw are only accessible by air.
I fly a 1977 Piper Arrow—not exactly a stereotypical high-wing, tundra-tired or float-equipped arctic bush plane—but a solid cross-country platform. As I had hoped, I was able to do most of the remote part of the trip VFR, but I had good IFR capabilities when needed (albeit with minimal capabilities in icing conditions). In the 42 years since I learned to fly, when most Alaskan airstrips were dirt or gravel, there is now a fairly decent choice of paved fields—although a multi-hour flight from one to the next—which are friendlier to a low-wing, retractable airplanes. Still, my route included a few unpaved strips. The trip took roughly 80 flight hours, and three weeks of elapsed time, starting in mid-June. This article focuses on the preparation needed for the trip.
IMPORTANT NOTE: Subsequent to my trip, in the current COVID-19 pandemic, both Canada and the State of Alaska have imposed stringent conditions, including restricted Ports of Entry, amount of time in transit, and need for COVID testing and/or quarantine for transit from the United States into and through Canada and subsequent entry into Alaska. Regulations are changing with conditions, and I strongly recommend that you research your options before undertaking this trip.
There is a lot of preparation for any long cross-country journey, but this trip had two elements that I hadn’t had to include in any of my trips before. These are the specific items needed for flying from the US through Canada, and the preparations for survival, in case of a forced landing, potentially hundreds of miles from the nearest town or road, across a largely uninhabited and often rugged wilderness.
There are four items needed to cross into and out of Canada, in addition to the normal documentation needed for domestic flights. These include FCC Radio Station Authorization for the airplane, FCC Restricted Radiotelephone Operator Permit for at least one pilot or crew member, a Customs and Border Patrol Annual User Fee decal, and registration in eAPIS, the Customs and Border Patrol Electronic Advance Passenger Information System. You will also need proof of insurance.
For all of these items, my advice is, “Start early! You may hit unexpected obstacles.” For example, after starting my preparations, I learned that, due to the partial government shutdown in January 2019, the average processing time to issue a Customs decal doubled from the expected six weeks to 12 weeks. The Radiotelephone permit for the aircraft took six weeks. Fortunately, the Operator Permit came in only a few days, and the eAPIS registration was completed immediately. The personnel on the various agencies’ help desks were very pleasant, but the process can take a long time. This isn’t a problem if you start several months in advance, but don’t put it off until just before you want to leave.
The key URLs for applying for these items are listed below. Keep your credit card handy – all but the eAPIS registration have a fee associated with them.
The list at the end of this article shows a checklist for my pre-trip preparations. Even if everything went as planned, I still expected to be landing in some very remote locations and needed to be pretty much self-sufficient when I got there. So the list includes some items I’d not normally carry for a multi-day cross-country trip in the lower 48.
It is worth noting that ATMs are not available at many small Canadian airports. My arrival (specifically taking a taxi from the airport to my hotel) would have been easier if I had arrived already possessing some Canadian currency.
I found it very handy to have all my documentation organized in a loose-leaf notebook, with each document in a page-protector. That kept everything handy and protected from wind/rain/etc. for meeting with the customs agent upon arrival.
A forced landing is always a daunting proposition, no matter where it occurs. But flying across the Alaskan or northern Canadian bush takes the concept to a much higher level. Much of this trip was across very remote areas, including mountains, vast forests, and a profusion of lakes, where any forced landing is likely to be more than a hundred miles from the nearest human. The likelihood of an airport, road, or cleared field within gliding distance is minimal. Survival preparations better not be of the “lunch and a bottle of water” variety, rather the survival gear to be carried must be sufficient to support the people aboard for at least a week, before help can arrive. It includes food, water, shelter, protection, and signaling.
A complete checklist of the survival gear I took is shown below.
Both Canada and Alaska law require all cross-country aircraft to carry survival gear. Both requirements assume that, due to remoteness, bad weather, and lack of infrastructure, you should expect to be equipped for a week before rescue. An excellent summary of the legal requirements of each is available at Equipped to Survive. Although the requirements have changed in recent years, and are not now as specific as they used to be, their overall meaning hasn’t changed. Summertime survival is somewhat less intimidating than an arctic winter, but it can still be difficult and life-threatening. I worked as a field geologist for seven years in Alaska, and the list noted below contains the items (which exceed the legal requirements) that I feel are appropriate for a week-long enforced stay in the summertime Alaska/Canadian wilderness.
It is worth noting that an important item has recently become feasible to include in the survival kit. While they are still quite expensive to purchase, several vendors now offer to rent satellite phones for a reasonable price. Prior locator beacon technologies could tell rescuers where you were, but couldn’t let you communicate why you were there or what you needed. Did you have engine failure, run out of fuel, or get a flat tire on a remote strip? Is anyone injured? Is the airplane flyable? A sat phone will allow you to communicate with rescuers before they come. Even if it takes days for rescue to come to you, you can ensure that when they come, they bring what you need.
A trip like this is daunting, but do-able. You can’t ignore the need for preparation, but given thoughtful planning and sufficient time, you can indeed be ready for the trip of a lifetime.
Proof of insurance (needed for travel through Canada)
Canadian charts, approach plates, CFS chart supplement
American charts, approach plates, chart supplements, Alaska supplement
ForeFlight Canada upgrade
Jeppesen Canada data for Garmin 530
Case of engine oil
Two spare oil filters
Full oxygen bottles
Cowl plugs, pitot cover, gust lock
Window cleaner and microfiber towels
Note that quantities of food, water, and camping gear need to reflect the number of people aboard.
Food (sufficient for one week)
Water (minimum two liters) and water filter and/or treatment pellets. Remember that the freeze-dried food that you brought requires quite a bit of water to reconstitute, and you may not have a nearby water source.
Stove and fuel
Plate, cup, fork, spoon
Sleeping bag and foam pad
First aid kit
Bear spray. Note: If a can of bear spray burst inside your airplane while in flight, it would be a life-threatening emergency – imagine your plane filled with pepper spray!. Carrying your bear spray inside a sealed PVC-pipe container can mitigate this risk.
Shotgun and ammunition. Note: Canada does not permit handguns or any semi-automatic firearms. If you elect to carry any firearm on your airplane, you will need to file a “Non-Resident Firearm Declaration” (Form RCMP 5589 / CAFC 909) with Canadian Customs when entering Canada. See this website for more information.
Lighter (two) and/or waterproof matches
Signaling devices (flares, signal mirror). Flares are not very effective in sunlight, and are quickly expended. A mirror can signal for a long time—particularly effective after a rescuing aircraft has turned toward you and is trying to spot you on the ground.
Like some of you, I have throttled way back on my flying (OK, ripped it to idle actually) until the COVID-induced fog lifts. Looks like I’ll be another non-current pilot, anxious to re-introduce myself to the cockpit, safely and smartly, when the personal distractions subside a bit.
However, like a lot of you, I’ve also been taking advantage of the absolute deluge of Zoom-based hangar fly chats, virtual pilot get-togethers, IMC/VMC Club meetings, YouTube videos, online courses, classes, seminars, webinars… it is like being locked in a candy store full of free flying stuff!
There is an abundance of sources you can tune into, and learn all about the “Top 10 Things You Must Know” about the “Top Five Things That Every Pilot Must Remember” about the “Three Absolutely Essential Things You Must Master…” to be able to handle the “Number One Most Critical Thing Every Great Pilot Must Be Able to Do.”
…fly the plane?
Anyway, I want to address one of my favorite topics: in-flight emergencies. (I’m going to switch to using “EP” for brevity). Although EPs are one of the most common subjects discussed during these electronic gatherings, they deserve a much deeper dive than just the basic “Establish Best Glide Speed and Pick a Suitable Landing Spot” stuff.
I am always interested in polling groups to see who has had an actual, real-world, heart-pounding, adrenaline pumping, seat cushion-sucking EP; where, despite your supreme confidence and phenomenal piloting skills, the much-preferred Happy Ending wasn’t guaranteed until you stepped onto solid ground.
I am surprised, but happy, with the relatively low number of pilots that have had one: that’s a good thing. Experiencing a significant EP is not a square you must fill to be considered a “complete” pilot. Unless you fly taildraggers. In which case you are expected to join the “Those That Have and Those That Will” Ground Loop Club.
For some reason, I have had several major EPs in both my civilian and military flying activities. (Maybe that’s why no one wants to fly with me?) Fortunately, they have all ended well, so far.
A few of the more memorable ones, which I have no problem recalling in vivid detail, include:
PA-28-140: Engine failure on takeoff, over water, with two students on board. I set up to ditch; then decided I could get back to the airport; we made it over the airport fence, but not quite to the runway.
PA-25-150: Engine failure while towing a glider, in the mountains. Luckily, it happened high enough that the glider and I could both get back to the grass airstrip. I had to slip to a landing with my head sticking out the left side window/door; the windshield was covered with oil.
I say “engine failure;” in both cases, an O-320 cylinder cracked around its base, and the engine kept thrashing itself at a low RPM until I pulled the throttle to idle; then it froze. I should maybe stay away from O-320s.
Continued VFR Flight into IMC #1: On my long commercial cross-country, not instrument rated yet. Over northern Florida, I was forced lower until I was committed to landing on a road. After pulling up to miss trees, power lines, and a traffic signal, I decided instead to climb up through the soup and declare an EP; I got vectored to the nearest airport (TLH), and then down through solid IMC to a 2-mile final (vis was right at 2 miles). Worked like magic. After landing, the only thing the controller said was, “Have a nice day.”
Continued VFR Flight into IMC #2: Now a CFI; flew cross country from Anchorage to Valdez in a Cessna 182. I took the inland route via Thompson Pass. Blasted off out of Merrill Field and was immediately scud running. It was just plain stupid in so many ways; never mind the details.
F-15A: Left engine (P&W F100) exploded/disintegrated/left the airplane, literally, during a high-G, basic fighter maneuver training sortie. Rained parts all over the New Mexico landscape. On landing, found the left engine bay was “vacant.” Shrapnel went through the bulkhead and damaged the right engine as well. It failed during shutdown.
F-15C: Rudder actuator failure, resulting in a rudder “hard over.” One rudder locked in a fully displaced “inboard” position; the other rudder tried to compensate to maintain directional control. Over East China Sea, 100 miles northwest of Okinawa. First (and still only) time that has ever happened in an F-15.
B-1B: Intense fumes in the cockpit; over the Pacific Ocean at night. Could not determine the source; turned out to be a disintegrating air conditioning unit.
I have also had a fair number of regular, run-of-the-mill EPs: various failed or degraded hydraulic/electric systems, nav and/or comm radio malfunctions, minor engine malfunctions (compressor stalls/stags, afterburner blowouts, bleed air overheats), flaps that wouldn’t do as commanded, hot brakes, failed brakes, high oil temps + low oil pressures, overheating avionics (ironically, due to icing conditions).
I have also had unlocked doors/canopy in-flight, bird strikes, bat strikes, lightning strikes, plugged up toilets, and a couple significant physiological episodes. Oh yeah, flew into a thunderstorm at night, in formation.
All these were relatively easy to handle and, in general, not that exciting (except for the thunderstorm thing…), usually because there were systems redundancies, or other ways to mitigate any loss of capability.
The other factor that helped immensely is the US Air Force’s absolute obsession with safety, emergency procedures, and systems knowledge. We spent an extraordinary amount of time and energy focused on handling emergencies under peacetime and combat conditions. From the infamous daily “Stand Up” in undergraduate pilot training, where if you goofed up in handling an EP, you were grounded; to hundreds of hours in cockpit procedure trainers and full flight simulators; to briefing an EP before every training flight and combat mission. We also had monthly (and sometimes weekly) written tests where we had to recall the BOLD FACE steps for every applicable emergency procedure… verbatim… including punctuation.
There are a billion things that might constitute an EP in your airplane. For all relatively modern airplanes, the manufacturers have addressed most major known malfunctions in the Emergency Procedures section of your plane’s AFM/POH. On the other hand, if you fly a 70-year-old tube and fabric antique, you’re probably on your own.
I think we can all agree that regardless of what you fly, there are some universally bad EPs. They’re the obvious ones that announce themselves with bright RED warning lights, maybe a big “X” across a blacked-out MFD/PFD screen, various tones and buzzers, possibly even a soothing, but monotone female voice chanting “Warning, Warning…” into your headset. These may also be accompanied by visceral stuff like violent shaking, loud noises, blinding smoke, choking fumes, cabin pressure fluctuations… maybe a sudden departure from controlled flight.
Ones that quickly come to mind: engine failures, primary flight control malfunctions, anything on fire, certain untimely catastrophic system failures (like electrical failures, at night, single pilot, in IMC), running out of gas. Combinations of all the above. Basically, all the stuff the FAA wants you to report.
How you handle these are relatively “black and white” (my words) in terms of the steps you need to take to, as the USAF taught me
Maintain aircraft control
Analyze the situation and take the proper action
Land as soon as conditions permit
Seems simple enough. If you can fly the plane, accomplish all the applicable checklist(s), think clearly and objectively, and not panic, you have a rather good chance of getting down safely. Then if it is still not looking good, you can always eject.
(OK: Yes, I realize most of us can’t eject.)
Then there are the “gray” ones. They can be insidious; they may not announce themselves with warning lights, strange sounds, or seat-of-the-pants sensations. Sometimes it is something that’s not quite right with the plane, but not addressed specifically in the Emergency Procedures section. Or it’s a situation that is not addressed at all, and the pilot is basing his/her reaction on their own knowledge, experience, and sometimes… luck.
The classic “my engine gauges are still in the green, but not where they usually are” scenario, often leads to a “let’s just press on and continue to monitor” decision. Things can deteriorate over time and distance, and if you don’t recognize the signs that your plane is getting sick, you can fly yourself out of options.
Ever had a bird strike? You heard and/or felt a “thump,” in your Cherokee, but it didn’t come through the windshield, so you pressed on. No big deal, right, I mean, how much damage could it do? Usually there is no detailed checklist for that, other than to stop what you’re doing, slow down, assess the damage and controllability, and land as soon as practical.
Land as Soon as Practical vs. Land as Soon as Possible… a great topic for another discussion.
Turns out it wedged itself into the gap between your Piper’s stabilator and fuselage; you don’t even notice it during your descent on the approach, but it will take a Herculean effort to salvage the flare. Maybe it punctured your nose wheel tire? Maybe it ricocheted off your main gear wheel pant and punctured your wing tank? Probably worth landing sooner than later to investigate, while you still have enough gas for some options.
I had an itty-bitty, 1 oz. “Big Brown” bat hit the extended flap on my F-15, at night, on short final. It put a hole through it as if it were a cannon shell.
Working as a team
In my experience, in all these situations, there is always room for a helping hand, whether it is other crewmen in the cockpit, a wingman in another plane, or an air traffic controller sitting in a facility on the ground. How you use them is the key to success; but you must get them involved first.
Ever coordinate an airborne “battle damage check” with another airplane? How about a slow speed tower fly by so they can look you over?
Which leads to another topic I would like to touch on: the decision to “Declare or Not Declare” an emergency with Air Traffic Control (ATC). This is a great conversation starter and usually leads to some heated exchanges.
I am not going to list all the possible advantages of declaring an EP with ATC. I really cannot think of any disadvantages. Some facilities may be able to help more than others. Whether they can help you at all depends on the dynamics affecting your flight. One thing they absolutely cannot do is fly your plane for you.
I am surprised at how reluctant some pilots are to declare an EP with ATC, as if some stigma is attached to saying the “E” word, that follows you around for the rest of your flying life. What I find more intriguing is some folks who are the most hesitant to declare one have never had an actual “real world” emergency. Yet.
My question: what informed your decision on when to declare an emergency with ATC, or more importantly, to NOT declare one? Was it just parroting a carry-over philosophy from your past CFI(s)? (Remember the Laws of Learning.) Is it based on your own bad experience with ATC, or maybe a story about another pilot’s situation? Maybe it was getting harassed at a hangar fly for being a wimp?
One of my favorite answers: “Well it depends… on how bad the EP is.” Obviously, my next question is, “Well, how bad does it have to be before they ‘fess up and declare?”
Their decision to declare an emergency is an easy one when it is one of the bad EPs; conversely, it’s the “gray” kind of EP that leads pilots to struggle with the “Do I or Don’t I” decision; and unfortunately, it’s often the “don’t declare” option that wins out.
So instead of unequivocally saying the E-word, they will describe their circumstances, with no apparent sense of urgency, to a controller who may or may not be a pilot, who does not understand how dire their circumstances really are. Then they expect that controller to help them come up with a Plan B.
One of my favorite winter flying EP scenarios is icing.
I recently heard a very experienced CFI tell a group of mixed-experience pilots, that he would not declare an emergency in a situation where his Part 23, light single-engine, non-FIKI airplane started to ice up, just to get priority for an instrument landing, even though approach control told him to “expect vectors through final for spacing” while he was still several miles and minutes away from getting on the ground.
His rationale: “Seems a little extreme to declare an emergency just for that;” so, he elected to trundle along unnecessarily, with possibly more ambushes waiting between him and the runway. His single caveat: “I can always negotiate with the controller when I get closer.”
My response: NUTS. Why not declare the emergency, so the controller can give you priority, expedite your arrival, limit any additional low altitude maneuvering, eliminate additional ATC amendments or delays, help prevent other distractions, minimize your exposure to the “elements,” and even give the tower a heads-up that your directional control might be a bit “iffy” on landing. They might even “roll the trucks” for you as a precaution. That’s OK; the CFR troops don’t mind the exercise.
So now a room, maybe half full of inexperienced pilots, thinks declaring an emergency is “a little extreme” in cases like this, but they don’t have the subjective judgment yet to know if/when that might be true.
Happy to argue! entertain other points of view?
Having time to deal with an EP is a luxury. I have seen EPs that were handled well and ended well, ones that were handled poorly and ended badly, and ones that were handled badly and ended tragically.
The amount of time spent addressing the EP, while airborne, was usually a major factor in the outcome. The accuracy in identifying, handling, mitigating, and “accommodating” the impacts of the EP was crucial. The availability of additional help, and how it was used or not, was also a player.
When is an EP not an EP? What does it cost to declare one with ATC? What might it cost if you don’t?
I am fairly sure the FAA would rather you declare one then end up not needing any help, than not declare one and end up in a smoking hole because they couldn’t help you. Or they did not understand how much help you really needed.
Finally, FAR Part 91.3 reminds us that: (a) The pilot in command of an aircraft is directly responsible for, and is the final authority as to, the operation of that aircraft, and (b) In an in-flight emergency requiring immediate action, the pilot in command may deviate from any rule of this part to the extent required to meet that emergency.
Never hesitate to exercise that authority.
Please remember, you can always laugh about it when you’re safely back on Earth, surrounded by family and friends, and it wasn’t as bad as you thought. The FAA won’t even send you a bill… probably.
You’re pointed away from the destination airport on some controller’s vector and you are sweating the near-empty fuel gauges. You can’t be certain when you’re going to be turned toward the airport and how long it will take to get there.
As a last resort you tell the controller you are minimum fuel and need priority to the runway. Did you violate FAR 91.167, the rule that sets the requirements for minimum fuel when flying under IFR?
The only certain answer is “maybe.” The reason is that the FAR describes required flight planning, not the actual amount of fuel in the tanks. If you made a credible flight plan and fueled the airplane accordingly, but some unforeseen event caused you to run short of fuel, you may not have violated the rules.
Even more confusing is the title of FAR 91.167, which is “Fuel requirements for flight in IFR conditions.” Look at FAR 1.1 definitions and it says “IFR conditions” are weather conditions below VFR minimums. If you’re flying on an IFR clearance in VFR conditions do the minimum IFR fuel requirements apply? Or is it the lesser minimums for VFR fuel under rule 91.151? I don’t know. And that’s why if you make it to a runway without losing power from fuel exhaustion you may not have violated any FAR.
Another potentially confusing component of the minimum fuel requirements in the FARs is the definition of the quantity of fuel required. For both VFR and IFR flight planning the reserve fuel is expressed enough fuel to fly for either 30 or 45 minutes at “normal cruising speed.”
What the heck is “normal cruising speed?” Most airplane flight manuals or pilot operating handbooks show true airspeed and fuel flow per hour for three cruising conditions—normal, long range, and high speed.
Sounds simple enough. Look at the chart labeled normal cruise, multiply the hourly fuel flow by .75, and that’s the FAR required reserve fuel amount. But that chart will show cruise and fuel burn at a range of altitudes across the airplane’s operating envelope. And the airspeeds and fuel burns will be dramatically different at various altitudes. That’s particularly true for turbine-powered airplanes where fuel flow can easily be double, triple, and more when flying at 3,000 feet instead of a typical cruise altitude far up in the flight levels.
If you want to fly by the rules you could legally plan a flight with a reserve that represents just 45 minutes of fuel burn at an optimum normal cruise altitude as reserve. Legal, yes, but that makes no sense.
The intent of reserve fuel is to accommodate the unexpected. A wrong forecast for winds aloft en route can make hash of any flight plan. So can an unexpected and longer routing clearance from ATC. Unfavorable altitude assignments, particularly in turbine flying, can also burn up extra fuel at a furious pace.
Then there is always the possibility of air traffic and airport system failures. If an airplane slides to the edge of the runway at your destination and wipes out the gear it’s going to take a long time to clear it. This time of the year over much of the country snow removal activity can close an airport for an extended and impossible to predict time. And there is always the possibility of equipment outages in the ATC system that create considerable delay.
That happened to me not long ago on a trip into Bozeman, Montana. While we were still about a half hour out, Big Sky Approach Control lost its radar. That meant airplanes had to be separated “manually” in the terminal area. So we sat in a hold at an initial approach fix for nearly 40 minutes, waiting our turn for the approach. The weather was well above minimums, but until the tower had the arriving airplane in sight, the next airplane couldn’t be cleared for the approach. That would have been a real crisis if only the legal 45 minutes of fuel had remained at the destination.
The best news is that the computerized flight planning services—supported by really terrific improvement in winds aloft forecast accuracy over the last 20 or 30 years—has made precise fuel planning a snap.
My favorite flight planner is fltplan.com. Many swear by ForeFlight. Over the years flying a variety of airplanes I’ve found fltplan.com to be uncanny in its precision. It is a big surprise if fltplan misses time en route by five minutes on a three hour trip. And fuel burn predictions are reliably within a few pounds.
But fltplan plans by the rules. It calculates fuel burn based on route, cruise altitude and winds forecast. It does the same to plan fuel requirement to fly to the destination, and then the fuel needed to fly to the filed alternate airport. And then it adds in the amount of taxi fuel you have specified and calculates 45 minutes of fuel burn at your selected cruise altitude and power as the FAR-required reserve fuel amount at the destination or alternate airport.
Fltplan shows this fuel total as “minimum dispatch fuel,” and the emphasis is on minimum. It’s the least legal fuel you can depart with based on the considerations of winds and routing. And that’s the starting point.
For example, in the King Air 350i that I fly, fltplan calculated a reserve of 512 pounds for one trip, and 441 pounds for another leg on the same day. The difference was created by planning a higher cruise altitude on the second leg, where fuel flow would be lower at normal cruise. So fltplan did the “legal” calculation and included 45 minutes of fuel at the higher altitude where I planned “normal cruise.”
The real fuel load I want includes a fixed reserve, not the “legal” amount. My real reserve is one hour of fuel at a realistic cruise fuel burn. In the King Air 350 that’s 750 pounds of fuel. And even that number is not truly fixed in my planning because doubts about weather forecasts, or bizarre routing that you can get in busy airspace, or unfavorable altitudes along many routes, add to my reserve.
It’s tempting to think the FARs found in Part 91 are conservative, even safe, but they are really bare minimums in many instances. And fuel reserve planning is one of those.
If you are into the sort of thing that warrants full tanks of fuel for every flight, then you are already in the realm of those who live to read these tales. Otherwise, this one is for you. You see, flying with a half tank of gas when the trip requires more is asking for a prayer at some time before you reach your destination.
Imagine if you will, over rocky terrain or a congested area or an uninhabited wooded lot, the last drip has dripped and the fumes run out and the engine coughs and coughs and cannot seem to quench its thirst and finally out of sheer exhaustion, it quits. What to do? What will you do? While in an armchair next to the warm glow of a fireplace and a cup of tea, you might say, “I will do this or that.” True enough, but then there is that time when it actually happens, and your life is on the line. What then?
If you happen to be flying one of those aircraft with a BRS chute, you might say, “No problem, I will exert my 45 pounds of force and pull on the overhead handle and come down safely with the parachute.” Umm, yes, that is possible but there is always that 14lbs/sq.in. gravitational force that on impact might claim a few linear compression fractures of the spinal vertebrae, among other things. And if your aircraft is not equipped with the BRS system then there is only the wind-hushed glide and a loud prayer.
Landing in a field is fraught with some danger of terrain and rocks and bushes that can cartwheel the best of the best. On a road there is always the landlubber crowd driving their four-wheelers around, messing up a perfectly great landing strip of a straight road, along with the power lines and the road signs, oh my! Add the murkiness of the dark of a moonless night and the complexities abound. The black holes suddenly emerge everywhere, and the mind wills itself to see spots of lights where none exist. You frantically press the NRST button and find that the closest airport is just out of reach and gravity has a date with the aircraft at that time. And you were only going for a dinner with some friends that night. What a shame! Isn’t it?
So, it behooves us as pilots to always have a trick up our sleeve: situational awareness and anticipation. As Shakespeare eloquently (when was he ineloquent?) said, “There’s a special providence in the fall of a sparrow. If it be now, ’tis not to come. If it be not to come, it will be now. If it be not now, yet it will come—the readiness is all.”
NTSB data from various aircraft sources tell a bit different for each aircraft. As John Zimmerman has pointed out, “And by far the most common reason piston engines quit is because they don’t receive fuel, either due to fuel starvation (the airplane has fuel but it doesn’t make it to the engine) or fuel exhaustion (the airplane truly ran out of it). These two causes account for over one-third of engine failure accidents, but they are completely under the control of the pilot.” NTSB data on Beechcraft piston engine aircraft point to fuel starvation/exhaustion/contamination as causal in 90% of engine failures.
One such unlucky pilot a long time ago had fuel starvation happen to him on a two-mile final at an airport and he tried to stretch the glide. As the yoke shuddered and then the airframe responded with equal vigor to the shudder, all went black as the wing dropped and the aircraft followed suit from only 200 feet into a ditch; a huge momentum-stopper. The other wing had plenty to fly another 200 miles.
So 30%-90% of these unfortunate accidents can be avoided by filling up the tanks. After all, if you fly for personal or business reasons, either way, fuel is the cheapest insurance. Isn’t it? There is just one more hiccup that we might face on takeoff and that is fuel contamination. It behooves us to drain the fuel on each tank and the lowest sump site to make sure there is no water or other contaminants. Water can accumulate from a rainfall while the aircraft sits idly outside, due to leaky O-rings. So, sump the tanks well and smell, look and confirm, “Clear of water and contaminants!”
Fuel starvation by its very nature is a fuel mismanagement issue either due to distraction, not following checklists for timed switch between tanks, inappropriate switching to the wrong tank, or unfamiliarity with the fuel system in the aircraft. In some twin aircraft, cross-feeding from auxiliary tanks on takeoff instead of the main tanks while in others switching the lever partially in between the two tanks can lead to engine failures at precisely the wrong time. All these errors of distraction and improper actions by the pilot have been known to cause grave harm. One of my habits on long cross-country flights is to change fuel tanks near an airport along the flight path. Just some dumb thinking involved here, without any stats to support but it gives me some added comfort.
The above graphic, from the ATSB, depicts the mindset in fuel exhaustion and starvation: preflight miscues, decisions in flight, and technical factors (although not specified, they probably include partial turn of the lever or switching to the wrong tank.
Fuel exhaustion, on the other hand, is mostly a miscalculation blunder in the face of a strong headwind and trying to reach a destination or at times in saving a penny for less fuel to lose a pound of flesh in a mishap. Planning for an alternate airport in a cross-country flight is both a comfort and a pain but it forces us to calculate the extra fuel to fly the 30 minutes or 45 minutes after the alternate, giving us extra bit of cushion from a propeller flailing in the air silently. And sometimes it is a matter of a wrongly placed decimal in the navigation log (rare, yet it happens). Sadly, human behavior is circumspect at times, and no amount of guessing and assuming followed by hoping will change the hard fact in the air.
Then there are the 10%. The traditional Continental and Lycoming engines have a failure rate of about 13 failures per 100,000 flight hours. However, it does seem that there is such a thing as “infant mortality,” when brand new or recently overhauled engines give up their compressions. Rare events, these, but if you are following along, the possibilities are there, based on statistics. Mostly these engines have some metallurgic anomalies or installation errors, and the weakest parts give up their hold and the whole system gets unglued and unbolted metal gets ingested and then after the biggest shudder and a riotous clanging, all is silence. There we have little to do or can do.
But if even 100 hours have passed and you are listening to the engine by doing oil analysis, looking for metal in the filter and the oil, you might catch it. In more seasoned engines the reliability is good once the engine achieves adulthood. If you treat that engine well and are not a power jockey with the candle burning at both ends, the engine will take you to the promised land of the TBO and perhaps beyond. Failed valves from unseating or asymmetrical seating, on the other hand, can be determined by compression tests and borescopes.
A short write-up from AOPA here will help in the understanding: The EGT and CHT supervision on a good engine analyzer can give a reasonable clinical diagnosis for the sharp-eyed aviator. Every pilot perhaps should strive to have one of these multi-probe engine analyzers in their aircraft. Monitoring the trend is how one can keep an eye on subtleties of mechanical failures along with the oil analyses and the gold standard of borescoping the pistons and valves. Remember, the top of the engine (pistons, cylinders, valves and valve guides) has more risk than the bottom part of the engine (crankshaft, crankcase, and in Continentals, camshaft as well).
Top-overhauled cylinders face a common enemy of early failures if the through-bolts are not torqued or lubricated to specs, according to data gleaned from various engine sites. So, a reputable shop has to be given the pilot’s authority to use new through-bolts when an engine is torn down for cylinder repair or grafting a new one. A little short-term extra expense but it is definitely a long-term safety profile. An improperly set bearing that loses oil supply is a precursor to a sudden prop stillness. And that virtue of safety belongs to a seasoned mechanic with plenty of hours under his or her belt.
Another likely scenario that might become an issue is after an annual is where the mechanic was distracted from putting the right pieces together, as with the ailerons or safety wiring parts. A family friend, a retired airline pilot, flew his Cessna off the airfield after an annual and the engine failed on takeoff. His experience in handling the emergency helped minimize injuries to scratches and a temporary limp, but the cause was the mechanic’s failure to secure the oil filter with safety wire. Small changes can have large effects. The saying goes, the butterfly flaps its wings and creates a hurricane somewhere. I don’t mean to disparage the mechanics, but simply bring to light the possibilities that exist, and it is the pilot’s responsibility to do a thorough preflight test and then on first post-annual inspection takeoff, perhaps fly in a climbing spiral over the airport before departing elsewhere.
Engines are very reliable nowadays. They go kerplunk from aforementioned reasons and from misuse or abuse of the engine by the pilot. Flying rich of peak at 100 degrees F from the leanest cylinder (or the first cylinder to peak) or 20-30 degrees lean of peak (from the richest cylinder or the last cylinder to peak) is fine. What is not good is to fly the engine at peak (unless the power is set below 65%), where the combustion timing and peak intra-cylinder pressures are the highest and create significant damage to the cylinder compartment and to the piston heads.
Treat the engine well and it will serve you for a long time. Sometimes too much is demanded of the engine in advance, and too little is promised in its support and care. One friend is on his third engine in 6500 hours, while an acquaintance is on his third engine in 2000 hours. It matters!
If you have followed along thus far, you will come to the same conclusion that I have: fly with $200 of fuel when only a $100 amount is required saves 90% of these engine stoppage events. Monitor the engine’s performance for trends and treat it with respect, and preflight thoroughly before each flight and especially after a mechanic has had it in the shop.
One more thing, although not the realm of this discussion but has to be mentioned: practice engine out scenarios with an instructor periodically to get the feel and flow of thought and action in assuming command of such a potential eventuality.
It was early morning just after dawn and the ATIS at Rochester, Minnesota, was advertising a runway visual range (RVR) of 1,200 feet. In the old days it would have also reported “sky obscured, ceiling indefinite.” Now it said “vertical visibility 200 feet.”
For some reason of geography or elevation, or whatever, Rochester seems to get more than its share of fog. I’m sure that’s the reason the airport authorities invested in the full approach lighting system and centerline and touchdown zone lights buried in the main runway. With those, the ILS approach minimum is 1,800 RVR feet instead of the standard Category I ILS 2,400 feet RVR minimums.
We asked approach control if the RVR was varying, and they said no. Austin airport is just over 20 miles southwest of Rochester so I asked to divert there. Austin was clear and I could see the runway not long after turning toward it. Approach cleared us for the visual, and a few seconds later issued a vector to a Challenger crew for the ILS approach into Rochester.
What? Oh, they said, the RVR had just bounced up to 1,800 feet. I told them give me a vector for the ILS, I really want to be in Rochester, not Austin.
This was going to be an ILS to real life minimums. There would be no “breaking out,” just a very quick look at the glow of the approach lights and then over the touchdown zone lights. It was a job for the autopilot, for sure.
The Collins autopilot in the King Air 350i did its usual perfect job of flying the ILS. When the radio altimeter system called “100 feet” I bumped the trim switch under my thumb to disengage the autopilot. It handed me the airplane in perfect trim and exactly on centerline over the lights. An easy landing.
So was that all legal? Yes. The autopilot in the King Air 350i is certified to be engaged down to 79 feet agl on approach. Do you know the operating altitude limitations for the autopilot in your airplane?
All autopilots have limitations, including minimum operating altitudes. They also usually have a limitation that you must be sitting at the controls with your seat belt fastened while the autopilot is engaged. I always chuckle at that one, but then I’ve heard stories from more than one pilot who has left the cockpit, trusting the autopilot to remain engaged and flying normally.
In general aviation airplanes the autopilot limitations are not normally in the “limitations” section of the pilot operating handbook (POH). The reason is that the autopilot system is not typically type certified in the airplane but is a supplemental approval. Because of that the autopilot limitations and other operating information is in the supplements section near the back of the book.
Autopilot altitude engagement limitations are for minimum altitude after takeoff, minimum altitude for cruise operation, and minimum altitude on approach. The restrictions are based on certification testing of what happens after a possible failure.
An autopilot quitting and doing nothing is called a “passive failure” because the system simply stops doing anything. That’s bad for a pilot who’s not paying much attention because—especially in the clouds or at night—the airplane could wonder off into a dangerous attitude before the pilot notices the autopilot has quit.
That’s a primary reason minimum altitude for operation in cruise is higher than on approach, or for engagement after takeoff. The certification theory is that any rational pilot is paying close attention to the instruments and flight path on approach or on climb out after takeoff, but in cruise flight none of us are riveted on the flight instruments 100 percent of the time. It’s also why all autopilots now have a loud, annoying warning sound, and usually flashing lights, to alert to disengagement, intended or otherwise.
A passive autopilot failure is not the worst possible. The most threatening is called a “hard over” where the system unexpectedly and without warning drives the flight controls to their limits with maximum autopilot authority.
Probably the most worrisome autopilot failure is a pitch trim runaway. Autopilots, just like we humans, use both the elevator and pitch trim to control the airplane. If the automatic pitch trim system runs away while the autopilot is engaged, the elevator servo will use all of its available muscle to resist the trim forces. But when the pitch servo runs out of authority, the autopilot will disengage, or continue to try to fly the airplane while the nose pitches up or down in response to the trim forces.
Either way, the pilot who experiences a pitch trim runway will be handed a badly out of trim airplane with totally unexpected control forces. Many pilots have mistaken those forces for autopilot actions even though the autopilot disengaged, or the pilot pressed the button to disengage the autopilot. Pilots who believe they are in a struggle with the automatic system rather than an out of trim airplane forget to simply retrim just as they would when hand flying. It’s easy to imagine how confusing and surprising such a situation can be, and how it can end badly, and many have.
During autopilot certification test flights, all of these failures are induced and must be handled safely by the test pilot. The key element here is “recognition time,” the time it would supposedly take for a normal pilot to identify the autopilot failure and react properly. The test pilot obviously knows a failure is coming, but must wait the specified recognition time before taking any action to simulate the “surprise” factor of a normal pilot having an unexpected failure.
Historically the recognition time for autopilot failure or trim runaway has been three seconds in normal flight. During approach the recognition time is cut to 1.5 or perhaps 2 seconds in the belief the human pilot is very alert and can identify the problem quickly.
Those recognition times have come under attack recently after the two crashes of the Boeing 737 Max blamed on failure of a stability augmentation system. As with an autopilot, the system was certified based on a time for the pilots to recognize a failure and react correctly. Recognition times have been in the certification standards since the earliest days of automated flight control systems. Maybe they are too short to accommodate the “average” pilot and give him time to identify and take corrective action after a failure. But as long as the human pilot is being “certified” as part of the system, a reaction time is the only way to include the pilot as monitor and ultimate pilot authority.
Take a look at the limitations for your autopilot. Most likely the minimum altitude will be 200 feet on approach. Many autopilot systems also have a flap limitation so using the autopilot with full flaps down to 200 feet may not be authorized.
I would suspect your autopilot minimum engagement altitude will be higher than the 400 feet that is standard in the turbine airplane world. And almost certainly it won’t be approved for cruise flight below 1,000 feet agl.
But when the weather is low and the approach is going to be close to minimums, let the autopilot fly. Even the FAA is so convinced of the superiority of autopilots that it lowered the minimums to 1,800 feet RVR on longer Cat I ILS runways that lack runway centerline lights as long as you let the autopilot fly down to decision height.
Hand flying down to bare minimums is something to do in training under the hood, or the simulator. In the real world of IFR flying the autopilot and flight director are the way to stay on the centerline all the way down to DH, and for some autopilots, even below that.
The impossible turn, for those of you not familiar with that term, refers to a single engine aircraft losing power after takeoff and executing a 180-degree turn and landing successfully on the same runway from which they just departed. The FAA’s official recommendation on losing power after takeoff is to proceed straight ahead and not to attempt to return to the runway or airport. That existing policy position by the FAA assumes there is an open area available for a successful touchdown. The second assumption is that pilot skill level is not sufficient to execute a 180-degree turn in order to return to landing without stalling and spinning in. Both positions are not much help.
The best advice at this time comes from the aviation master Bob Hoover. To quote: “Fly the airplane as far into the crash as you can.” Or as my original flight instructor once told me while discussing the subject, “Pick out the cheapest thing available and aim for it.”
Right now there are thousands of CFIs conducting touch and goes or options around the country. On the 1500 touch and go around the pattern and just before turning crosswind, they get the idea that it would be possible to perform the so called impossible turn and quite easily too.
Now, as I approach my 50th year of flying, aviation, engineering, and flight research, I can recommend an engineering approach along with my flight training experience on how to successfully conduct this emergency flight procedure.
So like any sound engineering and research project, we begin by asking ourselves the following:
Is there any literature on this subject?
Has this subject been researched before?
Is this emergency procedure maneuver conducted now?
Can this 180-degree turn existing maneuver be applied to single engine aircraft?
The answer to all of the questions is yes!
The literature search
Some time ago, I was lucky to locate several texts both published in 1947. The first, Airplane Performance Stability and Control, by Robert E. Hag and more importantly Technical Aerodynamics by Karal D. Wood.
Mr. Wood addresses the problem succinctly on page 289. He states, “Calculations on gliding turns are of practical importance because they permit determining the minimum altitude from which a return to the airport is possible in the event of motor failure soon after take off…”
Without reviewing the recommended math calculations here, he states this would show and determine helical path that may be considered wound on a cylinder and the altitude loss in completing a turn. The equations can solve for minimum loss of altitude in gliding turn.
He further states: “for minimal loss of altitude it can be shown that an angle of bank should be about 45 degrees and the wing should operate at maximum lift.”
So, what do we have here?
Mr. Wood has provided us with two data points:
It is aerodynamically possible to execute a 180-degree gliding turn successfully back to the runway.
An angle of bank of about 45 degrees may be used to do so.
So far so good. Now what is needed is the altitude to execute this maneuver, which way to turn (left or right), and why.
Approved FAA flight test standards and advisory circulars, along with accepted training manuals, provide an answer to our first questions: Is this emergency procedure maneuver conducted now? Can this 180-degree turn existing procedure be applied to single engine aircraft?
Our brethren who fly and instruct in helicopters and gliders practice this impossible turn while teaching and obtaining their respective ratings. With respect to our literature search, we will reference two glider publications plus an unlikely approach.
The Joy of Soaring, a training manual by Clark Conway from the Soaring Society of America.
The Art and Technique of Soaring, by Richard Walters.
It may be somewhat out of scope for this subject but the Space Shuttle—which is also a glider, by the way—had an emergency, 180-degree turn procedure. Fortunately, it was never used. I refer to the Return to Launch Sight, or RTL, emergency maneuver. When free from the solid rocket boosters and jettisoning the external tank, the shuttle was to execute a modified split-s maneuver and attempt to return to the runway. A gutsy maneuver to say the least. However, this proves the space shuttle did have an emergency plan if the need arose.
Soaring publications refer to the so-called impossible turn, known in the soaring world as the rope break procedure. Gliders are launched into the air by air towing from another powered aircraft referred to as a tug. Briefly stated, both publications recommend the key decisions height or point as 200 ft AGL.
Below 200 ft., recommended procedure is to land straight ahead. Above 200 ft., the rope break procedure is recommended to a downwind landing. At 1000 ft., a normal arrival traffic pattern is flown. So now we have two altitude recommendations to work with: 200 ft. and 1000 ft.
On the subject of which way to turn, turn into the wind. A turn into the wind will provide the least radius of action in the turn. Turning with the wind will cause the aircraft to drift away from the runway. The time spent realigning with the runway centerline may not allow completion of the turn or proper alignment with the runway allowing for a successful landing. Airspeed used by gliders is known as best distance speed. In a powered aircraft it would be best glide speed.
This is where we do not want the aircraft’s nose on or above the horizon. Keeping it there will get you into an accelerated stall. Not something you want close to the ground. Keep your nose below the horizon and your best glide speed. Let the aircraft proceed in a controlled spiral as stated previously by Mr. Wood.
Our helicopter brethren have an easier method in determining the best altitude and airspeed to employ in executing the impossible turn. In helicopter training and in actual emergency procedure, the student is introduced to the 180-degree autorotation procedure.
Altitude and airspeed for this maneuver is provided by a HV diagram or velocity/altitude graph. The graph shows altitude scale on the vertical axis and airspeed on the horizontal axis. Shaded areas on both axes indicates areas that autorotation, or engine out procedures, are not recommended. Read that as not successful. This H/V diagram can be found in Helicopter Flying Handbook 8083-21 on page 11-8.
Conducting my first 180-degree autorotation it was an eye-opening experience. Looking directly down is not recommended by the instructor. I did look anyway. It really got my attention and caused me to say bad words. The instructor found this very funny as I recall.
So important is this maneuver to the FAA and helicopter operations that this subject of 180-degree autorotation is also addressed in AC-61-140, Autorotation Training.
Why the comparison? Well gliders, while having a great lift to drag ratio, are somewhat slow in turning. What that means is while they stay up longer they do not turn quickly. Helicopters are handicapped by not having much of a glide capability, often referred to as the glide ratio of a crowbar. However, they can turnaround in their own airspace. Fixed wing aircraft fall somewhere in the middle. My 1939 Aeronca has a glide capability not unlike a Schweizer 2-33 training glider. A Cessna 172 easily performs an impossible turn. This type of emergency procedure both glider or helicopter must be done without hesitation. Both procedures are required training maneuvers that are demonstrated by the instructor and accomplished by the student before proceeding to the checkride.
Training and dog bones
So, what do we have to begin with? Mr. Wood has proven aerodynamically that it is possible to successfully execute a 180-degree turn with a bank angle of about 45 degrees.Our helicopter brethren train for this maneuver employing a HV diagram for altitude and airspeed in which to operate. The glider community employs 200 ft. AGL as the desired altitude, knowing the direction of the wind to determine which way to turn and keeping the nose below the horizon to avoid stalls in the turn. Both are required maneuvers.
Dog bones is a slang term for an abbreviated traffic pattern. After departing, make a 180-degree turn and land on the same runway downwind. Runway length permitting on touchdown, add full power, climb out and again cut the power and execute a 180-degree turn, landing on the same runway—this time into the wind. The name dog bones comes from the pattern the aircraft makes over the ground.
This procedure can be repeated until boredom sets in or ATC needs the runway. I have done this maneuver with students in various single engine aircraft in day and night conditions. During the day, this procedure is fun and after several tries the students really enjoy it. Night is more fun as you usually have the airport all to yourself. Have an experienced flight instructor show you how to conduct dog bones before trying them yourself.
What aircraft you fly will determine the altitude you know you can conduct a 180-degree turn and align with the centerline of the runway. When you are comfortable with handling the aircraft and noting how much altitude it would take for you to turn 180, that altitude would be your go-to altitude after takeoff.
Starting high at 1000 ft. is a good altitude. You know the best glide speed for your aircraft, or you should know it. Remember, do not keep your nose on the horizon when turning; keep it below the horizon, fly the spiral as stated, and a bank about 45 degrees or less. DO NOT rush or pull the aircraft around and tighten up the turn. Doing so will get you into an accelerated stall.
Remember, this is an emergency procedure.
When conducting your dog bone pattern, you will establish your comfortable altitude from which you know you can successfully execute the maneuver. Remember, your bank angle is about 45 degrees and do not exceed that. You know your aircraft’s best glide speed. Now you have the altitude you need, your aircraft’s best glide speed, and the experience you need to execute this emergency procedure.
When practicing this maneuver, you can add power when you find yourself not aligned with the runway or coming up short. Landing downwind will be tricky at first but with a little practice you can overcome the new experience and soon master it. In a real emergency, ground effect will carry you farther than you might think. If not, well, there are not many obstacles just off the end of the runway and taking out several runway lights is a small price to pay vs. an off-airport landing. It’s the best of a bad situation.
Find a good CFI, practice this often, and keep it in mind it is an emergency procedure to get you out of a no win situation.
Fly safe and let me know how it works out for you.