IFR for VFR Pilots

VFR pilots who stumble into IMC have a chance if they can resist the urge to overcontrol the airplane

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The pilot in command is the absolute judge of his ability to survive in the weather conditions ahead of the aircraft. When a non-IFR pilot has been operating in safe weather conditions and subsequently finds himself involved in an untenable weather situation, the near-universal solution is a 180-degree turn and a return to known, survivable conditions.

There is nothing so absolutely fundamental to a pilot as survival, and most people would argue there are few objectives that justify continuing flight into weather the pilot is not equipped to handle.

Survival is everything.

Youve heard the aviation saws a thousand times: There are two kinds of pilots – those who have gotten lost, and those who will, or those who have landed gear up and those who will. But theres another group that doesnt get as much press: those VFR-only pilots who have flown inadvertently into instrument conditions, and those who will.

The frequently disastrous result of this circumstance is supported by the aviation accident statistics, which show that there are still some non-instrument-rated pilots who havent gotten the word about trying to fly in weather conditions that deprive them of outside visual clues.

It doesnt take much to keep an airplane right side up or turn to specific headings or descend to assigned altitudes when youre flying under the hood in a training situation. You know that no matter how badly you might botch the job the CFI in the right seat will bail you out if you venture too close to the edge.

But its quite another story when your aeronautical situation turns to worms and the right seat is empty – or worse yet, occupied by a non-aviator who is not only no help but may well be more trouble than you need at a time like this.

The problem with flying into IMC is strictly physiological. Spatial disorientation is the result of confused signals from the bodys sensory systems. All aviators are potential victims, regardless of hours, and there are only two solutions: avoiding weather conditions that will induce spatial disorientation or flying by reference to instruments. It is, quite simply put, a matter of survival.

The accident record over the years leaves no doubt that pilots who are not trained to cope with instrument flight have a poor chance of surviving such an encounter. When your very survival is at stake, you need a lifesaver – knowledge or a procedure or a skill that will at least give you a fighting chance.

Thats why I developed an exercise in survival I call IFR for VFR Pilots. Its not intended to groom you for the instrument rating (although the fundamentals of IFR operations and techniques certainly wont stand in your way if you should decide to go for it), its not intended to provide a means of skirting around the law when weather conditions are less than legal for visual flight, and its not a panacea for every type of weather-related emergency you might encounter.

So what is the exercise in survival? Its the most basic, grass roots, fundamental type of lifesaver: a backup flying technique to help see you through this unhappy situation. Its a way to buy some time while you contact air traffic control for help. And once thats done, its a means to an end, because ATCs best efforts are worthless if you cant comply with instructions from the ground.

IFR for VFR Pilots will undoubtedly contribute to your overall flying skill, because the control techniques are just as applicable in good weather as bad. After all, the airplane doesnt know whether its flying in clouds or sunshine. But the primary purpose is to provide a lifesaving method that will enable you to cope with confidence.

Its Up to You, Pilot in Command
The most significant cause of weather-related accidents is characterized by the familiar statement, continued VFR flight into adverse weather conditions. Despite regulations and common sense, people still manage to fly themselves into weather they arent prepared to handle.

In the second paragraph of Part 91 of the FARs, the authors made you, the pilot in command, responsible for the operation of the aircraft and also gave you full authority to do whatever you think is best to solve the problem. In other words, all the rules go out the window when the situation progresses to emergency status. Its not a good place to be, but you need to know that you have really become the master of your own fate.

But in order to wield the authority, you ought to have the goods to back it up. If youve never been at the controls inside a cloud, its high time to experience all the illusions and strange sensations of flight when you lose visual contact with the ground. A few flight lessons in actual IMC should convince every non-instrument-rated pilot they have no business flying in potential IFR conditions, but that if it should happen, all is not lost.

The Anatomy of Confusion
Most everyone will lose their balance quickly when deprived of the sense of sight. But visual inputs are only part of the rather remarkable mechanism that continually answers the question which way is up? As you move about in your normal world theres a definite feel of the position you are in at all times.

Body sense informs you of vertical and angular movements by virtue of changes in the pressure and tension on tendons, ligaments, muscles and joints. Unfortunately this sense does not detect circular movements, and therein lies one of the unique problems of the aviator.

The third component of the human balance system is a set of semicircular canals embedded in your inner ear. These canals are filled with fluid and contain organs sensitive to even the slightest movements in pitch, yaw and roll.

When the inputs from vision, body sense and signals from the inner ear are combined in flight, you have a very trustworthy indication of your attitude relative to Mother Earth. The inner ear and deep muscle senses are important in the overall accomplishment of the objective, but the eye is the key; without vision, the other senses begin to play devilish tricks.

False sensations abound in the form of slow turns that arent detected, turns that seem to come to a stop but dont, climbs and descents that arent happening at all, and the feeling that youre turning to the right when you are actually turning left. You have become spatially disoriented.

This oversimplified explanation of spatial disorientation is intended to convince you of the one inescapable fact that must become the foundation of your thinking: without artificial visual clues (flight instruments) to replace the natural horizon, theres not a pilot alive who can maintain orientation for long. Humans simply are not designed for the task.

Equally important, since most contemporary airplanes are equipped with the basic flight instruments, is the training to use the visual clues thus provided. What good are the instruments if you dont know how to interpret them and control the airplane by reference to their information?

Its such a crucial point that it needs to be said one more time: the human balance system cannot operate satisfactorily in the absence of visual clues, and spatial disorientation will occur in a very short period of time when those visual clues are lost. In order to fly successfully when theres nothing useful to be seen through the windows of your airplane, you must be trained to use the artificial clues provided by the flight instruments.

There are techniques and procedures and special information to help the non-instrument-rated pilot overcome these problems, but theres no way around the flesh-and-blood simplicity of this fundamental point; you cant fly if you cant see outside and cant (or wont) use the artificial references provided on the instrument panel.

Weather to Watch Out For
Strange as it may seem, its not violent weather that most often causes problems for non-IFR aviators. When the weather is really bad most VFR pilots have the good sense to leave the airplane in the hangar and wait for a better day, or maintain a healthy distance from obvious cloud formations. Instead, low stratus clouds, fog, haze and poor visibility in general are the conditions that most often trap unwary pilots.

Just as mice dont get caught without deliberately going after the cheese, pilots arent trapped by weather. Clouds dont appear out of nowhere and engulf an airplane; pilots fly airplanes into the clouds.

Perhaps that last statement should be qualified a bit. In one circumstance – flying at night when a higher overcast shuts off moonlight and starlight – theres the possibility that you will inadvertently fly into a cloud you cant see. But an adequate study of reports and forecasts, observation of the weather conditions before the sun went down, and careful attention to lights on the ground as you proceed should provide enough clues to increase your awareness of the potential problem.

In any event, such an encounter leaves you with the best of all weather penetration options. Because you flew from clear air into the clouds, the most effective maneuver is the time-honored 180-degree turn, which will surely take you back to the clear air you just left.

There should be no flight so important, no trip so urgent that it cant be postponed if unfavorable weather conditions appear. Given the wealth of information available prior to a flight, the en route weather reports, forecasts and advisories that are yours for the price of a simple radio call or a few moments listening after youre airborne, and the unexcelled accuracy and timeliness of your own in-cockpit observations, you should never find yourself trapped in weather conditions that require skills you dont possess.

Survival Flying Techniques
While administering a presolo check to a beginning pilot I noticed all the classic symptoms of a tense person, one with genuine concerns about the outcome of the task at hand. The young lady was a little more voluble than usual, there was just a hint of a tremble in her right hand as she reached for the throttle, and the entire preflight conversation had been punctuated by a nervous little laugh I hadnt noticed before.

Once in the air she was obviously experiencing some difficulty keeping the airplane going the way she intended. The left wing kept dropping and as soon as she leveled the wings the left one would start down again. In addition to the other signs, she appeared to be hanging on to the control wheel for dear life, and the very weight of her arm was enough to produce a continuous roll to the left.

We straightened out the problem easily enough by changing to a more relaxed grip and the ride proceeded more smoothly and proficiently from there.

This episode points up one of the most common sources of trouble for the non-IFR pilot who finds himself in an instrument situation. Even very small control inputs will produce excursions from straight-and-level flight, and if it happens in the clouds the scene is set for spatial disorientation. As luck (and certain design criteria) would have it, the airplane axis most sensitive to control pressures is the roll axis. Without realizing it, white-knuckled wheel-grabbers will wind up in the very situation theyre trying so hard to avoid.

Most light airplanes will do a much better job of flying themselves under normal conditions than an untrained pilot can hope to do. For IFR survival flying, consider a hands-off technique that in most cases will provide a greater probability of survival than the inept actions of a pilot who doesnt know what to do, and may be in such a state of disorientation that he couldnt make the right moves even if he were properly trained.

In order to understand whats going on when you put this technique to work its necessary to review some aerodynamic foundations.

Nearly all airplanes are designed with a certain amount of stability; that is, when the airplane is displaced from straight-and-level flight it tends to return to that condition. Some airplanes accomplish this more readily than others.

An airliner is very stable because it doesnt need to execute rapid turns or other types of quick maneuvers, but an aerobatic airplane is not very stable – control forces are light and the airplane tends to remain in whatever attitude the pilot sets up.

Most airplanes are in between. They represent a compromise by having a lot of stability in the vertical axis (to control yaw), almost as much in the pitch axis (to control airspeed), and relatively little stability in the roll axis.

Your primary flight instructor probably demonstrated pitch stability by pulling the nose well up above the horizon and, using rudder pressure to maintain heading, released the wheel. Almost immediately the nose started down, went well below the horizon, then began to rise – all on its own – and pitched down again. After several such oscillations, each one a little smaller than the last, the airplane returned to its original straight-and-level flight.

Magic? Not at all. Most airplanes are designed so that the center of lift is behind the center of gravity. The nose-down force that results is partly offset by thrust – a safety factor of sorts because a lack of thrust (as in engine failure) causes the weight to assert itself and pitch the nose downward to maintain flying speed.

But thrust alone cant do the job. If it did, every change in power would cause either a climb or a descent and youd have an airplane that would climb and descend at only one airspeed. Enter the horizontal stabilizer, an upside-down airfoil that generates a tail-down force to hold the airplane level.

Add an elevator that can vary the downward force at the tail and now the pilot can keep the nose where it belongs. Now, extra thrust can be translated into more speed and reduced thrust means less speed, all while maintaining a constant altitude.

Left to its own devices, and in consideration of the fact that an airfoil produces more lift as airspeed increases and vice-versa, this pitch-control system ultimately finds an airspeed at which the nose-down force (weight) is exactly balanced by the tail-down force (lift) of the horizontal stabilizer.

The addition of a trim tab provides aerodynamic muscle to hold the elevator in a desired position. When the pilot discovers the angle of attack and power setting that will maintain altitude at a given airspeed, the trim tab programs the elevator for that speed. When the pilot keeps his hands off the yoke, an increase in thrust will make the elevator more effective and cause the nose to pitch up and a power reduction will allow the nose-down tendency to take over.

The response of your airplane to these built-in pitch stability characteristics will vary somewhat from high to low airspeeds, but at normal cruise speed the response will be quite satisfactory and there should be no need to consider changing airspeed until you are near the end of the flight.

The key to success in hands-off flying is airspeed programming – getting the airplane trimmed so that it will fly reasonably level at normal cruise speed. Unless the whole world begins to come apart at the seams, unless the laws of aerodynamics are repealed while youre in the clouds, you should be able to get yourself out of trouble without changing airspeed.

Once you get the elevator programmed for a survivable speed, dont touch the elevator trim. Power is now controlling altitude, and if adjustments are necessary make them small ones – perhaps 100 rpm or half an inch of manifold pressure at a time.

Youll need to descend sooner or later and when that time comes, squeeze the throttle until you see a reduction of 500 rpm or five inches of manifold pressure. The programmed elevator will set up a descent in the neighborhood of 500 feet per minute. Level-off is simply a matter of squeezing the throttle back to the normal cruise setting.

A climb is accomplished with the opposite procedure. Increase power by 500 rpm or five inches of manifold pressure and the airplane will dutifully raise its nose a bit and climb at about 500 feet per minute.

When you need to turn, keep your hands off the wheel and press the appropriate rudder pedal until you establish a 10-degree bank and hold it there until the desired heading shows up at the top of the heading indicator. Now gently press the other rudder pedal to stop the turn.

The secret is small, consistent amounts of rudder pressure – just enough to get the job done. Theres some skill involved here, and you must practice this technique before you need to use it.

You must also apply rudder pressure as necessary to keep the nose from moving right or left when power is changed. Theres a simple rule involved; add power and the nose will move left, decrease power and the nose will move right. Anticipate the effect and make the heading indicator stay put with whatever rudder inputs are required.

Does It Work?
You bet it does. A number of testimonials from pilots who escaped potential life-threatening situations bear witness to the value of learning to keep your hands off the wheel. Theres a lot more to be learned about getting safely out of the clouds (IFR navigation, flying a simplified VOR approach, using ATC radar, etc.), but this short version of the technique should help convince you that your airplane will indeed fly itself quite nicely.

The most important thing you can do is not get into weather in the first place, so we close as we opened:

The pilot in command is the final judge of his ability to survive in the weather conditions he observes ahead of his aircraft. When a non-IFR pilot has been operating in safe weather conditions and subsequently finds himself involved in an untenable weather situation, the near-universal solution is a 180-degree turn and a return to known, survivable conditions.

There is nothing so absolutely fundamental to a pilot as survival; and there is no objective that justifies the certain risk of an attempt to continue flight in adverse weather.

Survival is everything.


Also With This Article
Click here to view “Take Your Time Setting Up a Descent.”
Click here to view “Tricks and Traps.”

-by Richard L. Taylor

Richard L. Taylor is the author of 14 aviation books, including IFR for VFR Pilots: An Exercise in Survival, published by Aviation Supplies & Academics Inc., from which this article is derived.

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