There's nothing particularly hard about cranking an airplane into a 45-degree bank and letting it turn around. But if you think that's all steep turns are about, you're sorely misinformed.
So what are the elements related to steep turns? The overbanking tendency, load factor, and division of attention and orientation come to mind right away, but there are a few others. Understanding these elements is one of the main reasons we learn steep turns. But they're fun to practice as well!
And let's make this clear: A steep turn is strictly a visual maneuver. During the turn your eyes should be outside, and you should be using the horizon, nose position, and landmarks as visual references. You also should be judging the feel and the sound of the airplane to assess the load factor, and to sense whether you're climbing or descending. Only glance at the altimeter, airspeed indicator, and vertical speed indicator occasionally to confirm what the view outside is telling you, and to verify that the turn is stabilized. Steep turns, along with stalls and slow flight, are excellent maneuvers to develop your "seat of the pants" or kinesthetic sense.
The procedure
First, climb to a safe altitude. (Although no specific minimum altitude is listed in the PTS for steep turns, 1,500 feet above ground level could be a considered a minimum.) Next, perform clearing turns to ensure that you're well away from other aircraft. Establish the airplane at a convenient, easily remembered altitude at the manufacturer's recommended entry airspeed or, if none is stated, a safe airspeed not to exceed VA (maneuvering speed). The airplane's nose should be pointed at a suitable, easily recognizable landmark, such as a mountain peak, lake, small cloud, road, or a cardinal heading on the heading indicator.
Next, the airplane should be smoothly rolled into a 45-degree bank, using blended aileron and rudder inputs to maintain coordinated flight and elevator backpressure to hold altitude. Once the desired angle of bank is established, the ailerons can be neutralized, but the rudder pressure should be maintained for coordinated flight. During the turn, small adjustments in bank and pitch should be made to maintain bank angle and altitude. Airspeed should be checked, and if required, a small amount of power added to maintain the entry airspeed. The rollout should be started approximately 15 to 20 degrees prior to the desired roll-out heading. The rollout is just a turn entry in the opposite direction, again with coordinated aileron and rudder inputs. Elevator backpressure should be released to maintain altitude and prevent ballooning--the sudden increase in altitude that can occur when the wings are leveled without a corresponding decrease in pitch. The turn is complete when the wings are level and the controls are neutralized. If the turn was 360 degrees, the airplane's nose should be pointed at the original landmark.
| If steep turns are causing you trouble, the problem could be ergonomics. Try placing both hands over the top center of the yoke (above); often this area is padded. Many students find this to be an easier way to simultaneously apply left aileron and pull back on the elevator. If you're one of them, you'll soon be performing near-perfect, 45-degree steep turns (below). |
Standards
The PTS says that you must maintain your entry altitude within 100 feet and your entry airspeed within 10 knots, hold your bank angle within five degrees (which means between 40 and 50 degrees), and roll out on your entry heading plus or minus 10 degrees.
If these limits are exceeded, you could receive a "notice of disapproval" on your checkride, which is very disappointing for a student pilot trying to become a private pilot. That's why I recommend training to halve these standards--holding altitude to within 50 feet, airspeed within five knots, bank angle to within a couple of degrees, and rolling out as close to your entry heading as possible. After training to these tolerances, you're more likely to stay within limits given the added anxiety of the practical test.
Get ready
Now let's get back to the procedure and discuss each step. The first step is to climb to a safe altitude. On a checkride, the examiner may simply ask you to demonstrate a steep turn, without telling you to climb to a specific altitude first--as your instructor might. If you're worried that the altitude is too low, you won't be concentrating fully on your turns. Second, clear the area for other aircraft. Again, if you're worried about other airplanes, you won't be devoting your full attention to your turns. (But you must be sensible about clearing; after all, they do call them "practice areas" for a reason.) Third, get the airplane stabilized and pointed toward a landmark or on a cardinal heading. It should be trimmed, at the proper entry airspeed, and in steady, level flight. Take your time doing this.
The roll-in
Smoothly roll into your 45 degrees of bank using coordinated aileron and rudder inputs as described next. If the nose yaws before the wings bank (roll), rudder pressure is excessive. If the wings bank and the nose yaws to the outside of the turn, the rudder pressure is coming in too late. Ideally, no slipping or skidding is felt.
How fast you "roll in" can make a big difference in the quality of your turns. Be consistent to achieve good results. This is called roll rate, and it's measured in degrees per second. For example, if you rolled into a 45-degree bank in three seconds, your average roll rate would be 15 degrees per second. In fact, three to four seconds is a comfortable amount of time to establish a 45-degree bank angle for a steep turn. Besides, a slower roll rate makes it easier to nail the 45-degree bank angle without overshooting.
The rollout
Think of the rollout as a turn entry but in the opposite direction. Since the airplane will continue to turn until the wings are level (zero bank angle), you'll have to lead your rollout by three to four seconds, or the same time it took you to roll into the turn. Start your rollout about 15 to 20 degrees before your desired heading. Consistent roll-ins and rollouts are so crucial to making great steep turns they should be practiced on their own, until they become automatic. By controlling variations in roll-ins and rollouts, your headings, altitudes, and bank angles will become more consistent and accurate.
Altitude control
Take a look at the load factor chart (below). As you can see, the load factor remains virtually unchanged at roughly one G (the force of gravity) up until 30 degrees of bank, and only then does it start to increase. Actually, at 30 degrees of bank the load factor is a mere 1.15 Gs, only 15 percent more than at zero bank. At 45 degrees of bank, the load factor is 1.41 Gs, and at 60 degrees of bank, the load factor is 2.0 Gs.
This chart gives us insight about how much elevator backpressure is needed to maintain a constant altitude with changing bank angles. As you roll into your steep turn, almost no elevator backpressure is required until passing about 30 degrees, and then it should be steadily increased until reaching 45 degrees. The load factor at this point will be 1.41 Gs. In other words, a 100-pound person will be exerting a pressure of 141 pounds on the airplane's seat. With a constant bank, altitude, and airspeed, this load factor should remain constant throughout the turn.
The load factor chart also gives us clues about how to handle the elevator backpressure on the rollout. As you roll out, you should begin relaxing the backpressure immediately and continuously until passing through 30 degrees of bank, at which point all the backpressure should be gone. If you wait too long to "unload" the backpressure, the nose may rise and altitude may increase during the last few seconds of the turn. On the other hand, if you unload the pressure too early, before passing through 30 degrees of bank, altitude may be lost.
Ergonomics
Don't tell the manufacturers, but another issue that can become problematic during steep turn practice is the control yoke. Airplanes with side-stick controllers or sticks don't have this problem. With the student sitting in the left seat, and manipulating the yoke with his left hand, the hand, wrist, arm, and elbow geometry is not conducive to applying left aileron and back elevator simultaneously. It's a simple problem of ergonomics. Sometimes the student finds it difficult to maintain the required elevator backpressure, and the airplane loses altitude. A clever solution for this is to grasp the yoke by placing both hands comfortably over the top center or padded area of the yoke.
A challenge with side-by-side trainers is the different sight pictures for left and right steep turns. With the student sitting in the left seat, the engine cowling appears to rotate downward to the right during a steep turn to the right. This can cause the student to apply more elevator backpressure, resulting in an inadvertent climb. Conversely, the engine cowling appears to rotate upward to the left during a steep turn to the left. This can cause the student to relax elevator backpressure, resulting in a descent.
One of my favorite tricks is to fold a piece of paper to come up with a 45-, 45-, 90-degree right triangle. I would then affix this "right triangle" on top of the glareshield to provide two 45-degree reference lines. (The 90-degree angle goes at the top.) The student can bank the airplane until the horizon is parallel to the edge formed by the fold, and voila!, he'd have 45 degrees of bank without ever having to look at his attitude indicator. After a few practice turns with the "paper triangle," he'd know exactly what a 45-degree bank looked like.
Still another idea is to use a "racing stripe" to help develop an awareness of the longitudinal axis of the airplane. Before flight, place a length of masking tape from the front of the engine cowling to the base of the windshield parallel to the centerline of the airplane directly in front of the student's field of view. This stripe helps students to visualize the longitudinal axis and provides a reference line for steep turns.
Overbanking tendency
The overbanking tendency describes when an airplane is prone to roll into an ever-steepening bank. This is caused by a difference of lift between the inside and the outside wings. In a 360-degree turn, both wings complete the turn in the same amount of time. But since the outside wing moves through a larger circumference than the inside wing, it must have a slightly higher airspeed. This increased airspeed causes increased lift, which causes the outside wing to rise--increasing the bank angle. This difference in lift becomes more pronounced as the turn radius becomes smaller, as is the case with steep turns.
Opposing this tendency is the natural lateral stability of the airplane. All training airplanes have inherent lateral (or roll) stability about their longitudinal axis. This is the tendency of the airplane to return to a wings-level condition after a disturbance causes one wing to drop. This disturbance could be caused by a momentary wind gust or an inadvertent aileron input.
This delicate balance between the overbanking tendency and inherent lateral stability affects the way the airplane responds in shallow, medium, and steep banks. In shallow turns (less than 20 degrees), the overbanking tendency is so weak that the inherent lateral stability of the airplane acts to level the wings unless some aileron is applied to maintain the bank. In medium turns (20 to 45 degrees), the forces are generally balanced, and once established in the turn, the airplane tends to remain at a constant bank with little or no aileron input. In steep turns (45 degrees or more), the overbanking tendency overcomes the inherent stability of the airplane and the bank increases unless aileron is applied to prevent it. You may notice this tendency during your steep turns.
Distraction
According the FAA's integrated approach to flight instruction, the instruments should be cross-checked for bank angle, airspeed, and altitude information. The problem that many students have with this approach is that the instruments become distractions. A good workaround for this issue is to cover the attitude indicator, heading indicator, altimeter, and vertical speed indicator before starting the turn. After the turn is completed, the instruments are uncovered so that the students can see how well they've done.
So there's a breakdown of elements of steep turns. With consistency, practice, and a little smooth air, you'll soon be making perfect steep turns. And you'll know it because when the air is still, you'll feel a slight burble as you fly through your own wake on the rollout.
Christopher L. Parker is a CFI and an aviation author, speaker, and FAA remedial training specialist. He flies internationally as a contract captain on a Bombardier Challenger business jet and lives in Los Angeles.
Want to know more?
Links to additional resources about the topics discussed in this article are available at AOPA Flight Training Online.
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