I would like to share this article, written by Paul Furnee in March 2017 – legendary flight instructor.
To start with, it makes learning to fly a whole lot easier if you have a basic understanding of some of the aeronautical terms and anomalies particular to small training aircraft. It is easier to learn, if you have more AHA! moments than WTF! moments.
There are three important terms and aerodynamic characteristics that pertain to handling an aircraft almost any time, but are most important during your very first take off.
ANGLE OF ATTACK
This term refers to the difference as an angle between the direction the airplane is pointed and the direction it is actually traveling. You have seen this if you have ever seen a transport airplane landing. Note that it is actually pointing slightly nose up, maybe 3 or more degrees, but in fact is actually traveling down hill at about 3 degrees. The difference is called angle of attack and is sometimes represented by the small Greek letter Alpha.
Of course it is the wings that produce lift and keep the airplane from simply falling. At higher speeds, usually at cruise speed, the designed shape of the airfoil of the wing is sufficient to produce enough lift without a positive angle of attack. Some airplanes even fly at a negative angle of attack since their wings produce too much lift for level flight at high speed.
However, as the airplane slows down, it is necessary to “tilt” the front of the airplane up (and wing too of course) to keep it flying. Consider holding a flat board or even your hand out the window when driving, and note that you produce more lift if you tilt the front up.
The actual angle of attack of the airplane is not important except to test pilots, but it is good to know that if the angle is too much, the wing stops flying suddenly, and this is called a stalled condition. So as you slow down and increase the angle of attack to keep flying, there is a point where the wing stalls and stops producing lift. In most airplanes this point is indicated by the airspeed indicator, but in actuality the airspeed indicator only will be a good indicator when flying level and unaccelerated flight. It would be really nice if all airplanes were equipped with an angle of attack indicator, but they are not.
When flying an aircraft normally, about the only time angle of attack is important is during take off and landing, Of course these conditions are the most critical part of the flight, and this is why an understanding of the angle of attack is important.
The “P” in this case stands for “propeller”. This characteristic varies or does not even exist in some types of aircraft, but is almost always inherent in common training aircraft. Consider that most training aircraft have propellers and they are mounted on the front of the aircraft. This is called a tractor configuration since the propeller is actually pulling the airplane through the air.
As you accelerate down the runway for take off you will need to raise the nose in order to fly. But you will be at a relatively slow speed, so as soon as you raise the nose you will introduce an angle of attack. Since the propeller is firmly attached to the aircraft, it too changes the angle it “bites” into the air.
As the propeller rotates, the right side of the propeller is moving in a downward direction (Usually in most American airplanes), and the angle of the blade produces lift (actually thrust) much like a wing. When you increase this angle by changing the angle of attack of the airplane you will produce more thrust on the right side moving down, and less thrust on the left side moving up.
The result is that the airplane is being pulled through the air in an asymmetrical fashion, pulling the nose of the airplane to the left. This condition ONLY occurs at slow speeds and when the engine is producing thrust, which is exactly what is happening during take off. The correction for this is enough right rudder pressure to keep the nose pointed straight. Do not try to use the aileron control to correct yaw, since doing so only makes the situation worse due to adverse aileron yaw. (See below)
ADVERSE AILERON YAW
This condition occurs any time you move the yoke to command a rolling action of the airplane. Remember the yoke DOES NOT STEER the airplane, but simply ROLLS it to the desired bank angle. The severity of this condition depends on many factors including airplane design, aileron displacement, angle of attack, and in fact the speed of the airplane, and is always changing.
When you command a roll (move the yoke in a rolling motion) one aileron moves up and the other down. The aileron that moves down will induce a certain amount of drag fairly far out on the wing, and conversely the aileron that moves UP will reduce drag on the opposite wing.
If nothing is done about this, the nose of the airplane will “yaw” in the opposite direction of the intended roll, hence the term “adverse”. The slower the airplane speed, the more aileron displacement will be required and the angle of attack will be greater, both of which aggravate the situation.
Since the “yaw” control of the airplane is the rudder, the only way this “adverse yaw” can be prevented is to apply just enough rudder pressure simultaneous to any aileron displacement, in the same direction. Just how much is mostly developed by feel and experience, but the purpose of the leveling “ball” on the turn indicator is to indicate just how much rudder is needed. Any time the ball is not centered can be called uncoordinated flight.
It will take a lot of experience to develop this feel and since it is always different, don’t be discouraged if it isn’t perfect every time. But it is important to be aware of the condition and to try to correct it so that eventually it will become automatic.
TAKE OFF – LET’S FLY!
OK, so you’re at the departure end of the runway and have completed all the required pre take off checks and are ready to go. Your job now is fairly easy – just make the airplane do what you want it to do. YOU are in command! YOU are the driver! So let’s see how the characteristics above will affect you and your airplane.
When you enter the runway, you should really be ready. It is not acceptable to pull out on to the runway and sit there completing your checklist. But there is also no need to rush things. Take your time and carefully align the aircraft with the runway, and be in the CENTER of the runway. They put those centerline stripes there for a reason.
You’re all set to go. You might want to hold the brakes a bit while you begin to add throttle, but it is not necessary unless the runway is very short. Don’t be too hesitant with the throttle, but add power gently but firmly. Maybe about 3 seconds from idle to full power.
Initially your attention should be directed to keeping the airplane in the center of the runway with your feet. The yoke does nothing until you get some speed because these are purely aerodynamic surfaces that need airflow to function.
But soon you will make the transition from rolling to flying. When you reach a speed of about 30 MPH (It’s not really important) the flight controls begin to become effective and you need to manage them. First the rudder will become more effective, so smaller foot motions will have the same effect. It’s time to grab the yoke, but I use the term lightly. Just very lightly hold the yoke in your left hand and start holding a little back pressure (Nose up), not a lot, but maybe about 5 lbs to 10 lbs pressure. This helps give you a feel when the elevator becomes effective and when you will be able to “lift” the nosewheel off the runway. This will occur somewhere around 60 MPH depending on your airplane type.
As soon as the nose lifts off the runway you are effectively flying, even though the main wheels
may still be on the ground. Suddenly two of the above characteristics come into play. You will be establishing an angle of attack in order to make the airplane fly at a slow speed, and you will immediately note the “P” factor pulling the nose of the aircraft to the left. Anticipate that with a little extra pressure on the right rudder.
Never try to correct for “P” factor by using the aileron. Remember Adverse aileron yaw? It will just make things worse! Keep focused on the feet to keep the aircraft pointed in the right direction.
As you climb out from the runway, the most important parameter is airspeed. Let’s say you lifted off somewhere near 60 MPH. Aircraft manufacturers publish a best rate of climb speed, which might be around 80 or 85 MPH, and this is the target speed you should be trying to attain. But initially you will have no idea how steep to point the nose to maintain this speed. Since too slow is really, REALLY bad, too much speed is better than too little. So initially, only raise the nose of the aircraft enough to clear any obstacles which might be at the end of the runway. Don’t worry about the airspeed quite yet, unless your instructor is yelling at you “get the nose down”.
Maintaining a specified airspeed is best accomplished by NOT looking at the airspeed indicator. It will react much too slowly for you to make the proper adjustments. Rather, the correct procedure
is to point the nose of the aircraft where you think it should be, and then after everything becomes stable and constant, only then look at the airspeed and see what happened. If not correct, make a small change in attitude, and again wait until everything becomes stable and constant, and then check if the correction in attitude was sufficient. Initially this will take some experience, but remember that most training aircraft are not very good performers, so don’t plan on raising the nose too much. Again, it is better to be too fast than too slow.
Once you establish the attitude that will result in approximately the best rate of climb speed (called Vy), make a mental picture of it and use it on future take offs. Of course the attitude will vary a little bit depending on aircraft weight and density altitude, but don’t worry about that now. Just concentrate on maintaining this attitude while keeping the aircraft directionally straight with your feet. Sometimes it is difficult to see over the nose of the aircraft so you must use your peripheral vision OR THE AIRCRAFT INSTRUMENTS. It is good practice to intermittently lower the nose such that you can see the horizon, to check for other aircraft in your vicinity.
After take off and during climb, it is important to maintain maximum power. Most instructors will insist that you hold one hand on the throttle until at a safe altitude, generally 500 feet AGL or more. Climb, other than small adjustments during cruise, should ALWAYS be done at maximum power unless otherwise specified in the Airplane Flight Manual. Use MAXIMUM AVAILABLE power until you are at the altitude you wish to cruise, and you are also at the desired cruise airspeed.
STRAIGHT AND LEVEL CRUISE
This is by far the easiest part of flying, but it still takes self discipline and attention. Most sophisticated airplanes have autopilots in large part to control this portion of flight. The key words of course are “Straight” and “Level”.
Flying straight is accomplished by simply keeping the aircraft headed in the same direction. While this can be done visually by keeping the nose of the aircraft headed toward a distant landmark, the pilot must acknowledge the sidewards track or drift if there is a crosswind. This is why, however, most aircraft are equipped with a directional gyro or a stabilized compass, so the direction of the aircraft can be exactly managed. Small directional changes, such as from turbulence (or inattention), are best managed by using the rudder (feet) as much as possible and the ailerons as little as possible.
Level flying is accomplished primarily by using the pitch control. However, the reference used is important and changes depending on the condition. In very smooth air, the pitch can be adjusted for level flight and the trim (We haven’t talked about that but) can be used so that no pressure is needed on the pitch control to maintain the proper attitude. A pitch stable airplane can fly for a long time at a constant altitude without any pitch inputs if properly trimmed. This is the easiest axis to manage in calm smooth air. In turbulence, however, maintaining altitude can be a lot of work. But just like maintaining airspeed in a climb, do NOT look at the altimeter for primary reference to adjust altitude. It is best to change pitch (pressure) and hold it for a period of time and then check to see (on the altimeter) if the correction was sufficient. If you “chase” the altimeter, you will typically over correct. It is best for small altitude corrections to not use the trim, but for large corrections (>100′) the trim can be useful. In almost all cases, once airborne, the best technique for smooth flight and avoid passenger discomfort is to manage the airplane (Yoke and rudders) by applying (light) pressure rather than movement. This is quite different from driving.
PITCH, POWER, AND AIRSPEED
An understanding of the relationship between pitch attitude, power applied, and resultant airspeed is very important to control the vertical position of the aircraft. While roll and yaw can be controlled by the yoke and rudder, and are closely related, the vertical component is somewhat more complicated. A change in one component does not make an instantaneous change in the other, since time and inertia are involved. If you add or reduce power, the change in resultant airspeed is slow and delayed. The same thing is true if you change pitch attitude. The resultant airspeed change is slow and gradual.
In level flight, airspeed can be controlled by power alone. More power equals faster and less power equates to slower, at least over most of the speed range. Airplanes typically fly at about 65% to 75% of maximum sea level power, and as a result cruise airspeed is usually within a very narrow range. Only under the extreme conditions of maximum range does the power setting and airspeed vary significantly. It is good to note here that the airspeed varies as the cube of the power. So, twice the power will result in an increase of only about 1.26 (Cube root of 2) times the airspeed. For example if 100 HP will result in 100 MPH, then 200 HP in the same aircraft will result in 126 MPH. The lesson here is that it is not normally efficient to add power to go faster.
Normally when in a climb, airspeed is somewhat important because the aircraft has only one speed where it climb the fastest. This speed is called best rate of climb or Vy. Of course, normally when climbing, it is best to use maximum power, so in this case speed is controlled by pitch attitude. The BEST technique is to establish a pitch attitude that you THINK is correct, and hold it long enough (15+ seconds?) such that the airspeed stabilizes and is constant. Then if it is not correct, make a small change in attitude and hold it again.”Chasing” the airspeed indicator will result in wild excursions of pitch and lack of controllability.
During an en route descent, speed is not normally critical unless you are close to the red line (maximum permitted speed), but when on approach to land it becomes quite important. If you go too slow you fall out of the sky (That hurts!), or if you are going too fast you are in danger of flying past the airport. There are two ways to control the speed on approach: One, by varying the pitch you can control speed, and two, by varying power as in level flight. Depending on the conditions and circumstances, it is common to use both together. It also depends on the drag of the airplane. The more drag the airplane has, the more power is used to control airspeed, and pitch is used to “point the aircraft” at the runway threshold. A high drag airplane loses airspeed very quickly from a pitch up change, and gains airspeed very slowly from a pitch down change. Since low speed is far more dangerous than high speed, it is usually recommended that when the aircraft has high drag (i.e. with full flaps), that the glide path be controlled by the pitch and the airspeed be controlled by power. In both cases, you need to keep in mind that a change in pitch or power will NOT make an immediate effect on speed, but rather you must wait for the change to stabilize, so again do NOT “chase” the airspeed indicator.
OK. We’ve been told that what goes UP, must come down. So you have been able to master the aircraft in flight, but now comes the most interesting part. Landing it. Probably 90% of all training and practice activities in an airplane are concerned with landing the airplane (successfully, that is). This is not necessarily the most difficult part, but generally it requires the most precision and tactile skills. Landing an aircraft is a skill based exercise that must be learned and practiced. Every aircraft is somewhat different in it’s characteristics, but the basic techniques are similar.
Most “good” landings are preceded with a “good” approach. A “good” approach is one where all the parameters are preset and stable, and rightfully is called a “stabilized approach”. The first order of business is to get the airplane lined up with the runway. This should be done far enough from the threshold such that it allows plenty of time to adjust the glide slope, speed and trim etc. Initially this should be at least two miles from the threshold and no less than 500 feet above ground level.
Once lined up, big pitch changes are BAD! NEVER lose sight of the touchdown zone and NEVER raise the nose above level during the approach until you are over or past the TDZ (Touch Down Zone) and in the landing flare. The best technique is to “point” the nose (your best guess) at the landing point, keeping in mind that at slower speeds the nose will be a bit higher than the direction you are traveling (Remember ANGLE OF ATTACK). Also, once lined up, landing flaps should be selected (Usually full flaps – Make sure you are slow enough to do so – in the “white arc”), since the addition of flaps changes both the “sight picture”over the nose and the trim, both of which should be set as soon as possible when on the final approach.
Now, we’re lined up with the runway and have the flaps selected for landing. The next issue is to adjust the speed for the correct speed for landing. One of the purposes of the flaps is to provide drag such that the speed can be more easily controlled. Power will increase speed, but unless we have sufficient drag, it can be difficult to reduce speed. As above, in a high drag configuration, for the most part, you should maintain glide path with the pitch (“pointing the airplane”), and adjust the throttle for speed control. Using pitch to control speed works, but the speed change is slow to react and usually results in over compensation. Both methods of speed control can be used as needed, but using the throttle is generally more effective and doesn’t result in a departure from the intended glide path. This is particularly true if there is turbulence.
Once the proper speed and flap configuration has been attained, it is important to trim the aircraft such that very little or no pressure is required on the yoke to maintain the correct airspeed. Any
pressure required to maintain the intended glide path will then alert you that a speed adjustment is necessary without the requirement of looking at the airspeed indicator. At this stage of the flight it
is critical that your eyes are “outside” the aircraft, assuming, of course, that you are not in instrument weather conditions. You are now on a “stabilized approach” and no further changes should be made until you are directly over the TDZ except for MINOR adjustments of the throttle in order to maintain the desired speed.
We are now over the runway in the TDZ (First 1000 feet). At this point we need to raise the nose (slowly) such that we stop the descent and land on the main wheels . This is what takes practice.
Generally the throttle can be reduced to idle, but on some aircraft a small amount of power results in a better (but longer) landing. Initially it will not be evident to you how to slowly to raise the nose sufficiently to stop the descent without “ballooning” or gaining altitude. What is necessary is some feedback to you that will tell you whether the pitch action was sufficient or too much. One way to provide this is to “oscillate” the pitch movement very slightly. By pulling the yoke back perhaps slightly more than needed and then relaxing it, will provide a motion of the aircraft that can be measured. After several (very small) oscillations you can “feel” how much pressure or movement is needed to just barely fly the airplane over the runway.
Once over the runway and in the landing “flare”, the idea is to attempt to keep the aircraft flying as long as possible just inches above the runway while reducing speed. To judge just how high you are above the runway requires that you focus your vision a certain distance in front of the aircraft. This distance depends on the individual and the aircraft, and will take some practice, but it is this judgement that determines whether the landing will be smooth or rough.
Different and additional techniques will be required if flying a conventional gear (Tail wheel) aircraft or if there is a crosswind. But assuming either zero wind or wind directly down the runway, the major emphasis is pitch for altitude control and rudder for directional control.
Once you are safely on the runway and below flying speed, it is important that you realize that you are not done flying. Many accidents have occurred on the “roll out” by inattention or inappropriate actions. In almost all cases it is good practice to keep the yoke back until you are near walking speed. Secondly, the only emphasis after landing is to maintain the runway centerline and to slow the aircraft until you are again near walking speed. Make sure that the throttle is fully at idle, maintain yoke aft, maintain directional control with the rudders and apply brakes as necessary.
Maintain the centerline, and NEVER attempt to make a turn off the runway until you are at or near walking speed, unless the runway has a designated “high speed” turn-off. UNDER NO CIRCUMSTANCES should you retract the flaps until you are clear of the runway and stopped.