In this article, we’re going to take a look at all the stalls a private pilot should know.
For many people learning how to become pilots, stalls are one of their biggest concerns. Stalls are a perfect example of why ground school is actually pretty important. All those hours you spend learning aerodynamics aren’t so that you can take up a career designing aircraft–although you could if you wanted to.
No, those hours of theory are geared to help you understand why the airplane does what it does when it does. And understanding stalls is one of the biggest goals.
What Are Stalls?
Stalls occur when the air stops flowing over the wing smoothly. The book defines a stall when the critical angle of attack on the wing has been exceeded. When this occurs, there is a dramatic reduction in the amount of lift being generated.
Most students know the wing will stall if air isn’t flowing for the most obvious reason–because the airplane is flying too slowly. Airplanes must fly faster than their stall speed, or else they will stall.
Looking deeper opens up a wide range of questions. The aircraft has published stall speeds, Vso and Vs1, but they are calculated under very specific circumstances. In other words, they aren’t set in stone, and the airplane might stall sooner or later than expected.
In fact, a plane can stall in any configuration, attitude, and airspeed. A slew of things can change the stall speed, including airplane configuration (flaps or no flaps, gear up or gear down?), weight, CG location, density altitude, and load factor.
So, as you dive into each one of those factors that might change the stall speed, you start to realize just how complex airplanes are and what aerodynamics really mean.
You’ll learn all of these ins and outs during flight training. To get started, check out the FAA’s Pilot’s Handbook of Aeronautical Knowledge, Chapter 5: Aerodynamics of Flight.
Why Do We Learn and Practice Stalls?
Why would part of learning to fly a plane include going out and stalling it–on purpose? That question probably pops into the mind of every flight student at one point or another.
Stalls can be dangerous. When we practice them for flight training, we do them at high altitudes and in safe areas. We also generally do them with preplanning and preparation. In these circumstances, they’re safe.
However, when stalls happen unexpectedly, near the ground, or are allowed to progress further than they should, they become dangerous to flight.
That’s precisely why it’s important to practice and learn stalls under the supervision of your flight instructor. You aren’t learning how to stall a plane.
Instead, you are learning what it looks and feels like when the plane is about to stall. Hopefully, you’ll learn how to get the plane safely out of it before a stall happens.
And, if you do accidentally stall it one day, you will know how to recover safely.
What Stalls Does a Private Pilot Need to Know?
With all this in mind, you might wonder what stalls you must learn during your private pilot training. The Private Pilot ACS (Airmen Certification Standards) only lists two stalls you must practice and demonstrate and two tasks requiring a firm understanding of stalls and their causes.
Power Off Stalls
Stalls are most dangerous when they happen near the ground. During any flight, there are two times when you are near the ground–takeoff and landing. Notably, you are also flying slowly during these times and, therefore, are more in danger of experiencing a stall.
So the two stalls that a Private Pilot practices are based on simulating those two events.
A power-off stall is a simulation of the approach to landing, sometimes called an arrival or approach stall.
You set the aircraft up like you are on final approach to a runway: low power, full flaps, gear down, and in a gradual descent.
Now, imagine you lose power and try to make the runway. But the plane is sinking too fast, so you pull up to maintain your altitude and extend your glide. As the airspeed bleeds off, the wing will eventually stall.
The stall can be recognized by the airplane’s stall warning system, a mushy feeling in the controls, a control buffeting, or even a change in the sound of the cabin noise. Some planes are also equipped with an angle of attack indicator showing the wing’s progression toward a stall.
Once the plane is in the stall, it will begin to sink.
Recovery from a power-off stall means reducing the angle of attack (putting the nose down), adding power, and reducing drag by raising the flaps slowly.
Transition into a climb and continue raising the flaps gradually.
Keeping the wings level throughout the stall using mostly rudder inputs is important since ailerons could exacerbate the stall and lead to a spin.
Power On Stalls
A power-on stall simulates that you just left the runway after takeoff. They are sometimes called departure stalls.
In this case, the plane is slowed until it reaches the speed at which it leaves the runway, usually Vr, although Vx or Vy may sometimes be used. Then, departure (full) power is added, and the plane transitions into a steep climb.
From here, the pilot continues to increase the angle of attack as if the plane isn’t climbing as expected. For example, this might be the case when a high density altitude has affected the plane’s climb performance. It doesn’t look like you will clear an obstacle ahead, so you keep pulling up to try to make it.
As you pull back, speed will bleed off, and the wing will stall. Sometimes, depending on design and loading, a plane suddenly drops its nose when it stalls. Other times, the plane will begin sinking with little change in attitude.
Power-on stalls generally look and feel very different than power-off stalls. Since the engine is operating at high power and high angles of attack, the plane’s left-turning tendencies are at their maximum.
Using adequate amounts of right rudder to counter them is vital, or losing directional control is possible. It’s also a good way to find yourself in an inadvertent spin.
To recover, the angle of attack must be lowered by pitching forward. Keep the wings level with proper use of the rudder. Maximum power is maintained, and speed is recovered to Vx or Vy into a climb.
Slow Flight and Spin Awareness
While they aren’t stalls per se, the ACS has two other tasks that require you to exercise knowledge of them.
Slow flight is flying the airplane and maneuvering at the edge of what it can do. If you changed anything, the plane would stall. You can operate in slow flight clean (flaps up) or dirty (flaps and gear down) to simulate approaches and landings, just like stalls.
Slow flight is a maneuver that every pilot wants to get good at. It shows you can handle the plane in any scenario.
Operating the plane in slow flight means being very close to a stall but not letting it stall. It means noticing all the cues the plane gives and immediately reacting to them to ensure the critical angle of attack is never exceeded.
The ACS also lists spin awareness as a knowledge task–Private Pilot applicants are not required to practice or demonstrate spins.
Spins are the dangerous result when an aggravated stall is allowed to get out of control. When one wing stalls more than the other, the difference in the amount of lift being made causes the airplane to roll. The result is a stalled plane that is rotating.
It can be a very fast and dramatic spiral toward the ground.
The Private Pilot ACS also mentions four other types of stalls that you must “identify, assess, and mitigate the risk of” happening.
These stalls you will study on the ground, and your flight instructor may demonstrate a few.
A secondary stall results from improper recovery from the first one. Imagine a power-on or power-off stall that occurs accidentally near the ground.
While the stall recovery requires that the pilot lower the nose to reduce the angle of attack, the ground is coming up quickly. Keeping the nose down may not be your first inclination.
If the pilot does not keep the angle of attack low enough for long enough to recover fully from the first stall, a secondary stall develops.
When a stall occurs at a faster airspeed than the published stall speed, it is an accelerated stall. Increases in load factor increase the stall speed.
The most common time this occurs, although not the only time, is during turns.
So, put simply, an accelerated stall occurs in a turn. The stall will occur faster than it would during straight and level flight. This is why turns made during slow flight should always be done with shallow bank angles and avoid steep turns in the traffic pattern.
A cross-controlled stall is a very specific and dangerous stall arising from one particular bad piloting habit. It occurs when entering a stall with aileron inputs opposite the rudder input. The classic accident scenario is a pilot who overshoots the turn to final.
Not wishing to overbank the aircraft, they use excessive rudder to try to get on the runway centerline. Then, to keep the wing from dropping, they apply opposite ailerons at the same time.
The resulting uncoordinated turn can cause the plane to stall suddenly and at a relatively high airspeed, catching an unprepared pilot off guard. Cross-controlled stalls are deadly when they occur on the turn from base to final.
To avoid them, it’s vital to understand why they happen and to exercise good piloting and decision-making skills. ALWAYS keep your turns coordinated. If you overshoot the turn to final and struggle to get back on course, it’s time for a go-around.
Elevator trim stalls occur when the aircraft’s trim setting forces the nose up suddenly as the pilot adds power. This is a problem during a go-around.
The plane is trimmed for a power-off or low-power descent. If the pilot commands a go-around, the extra prop wash on the elevator suddenly forces the nose up and takes a lot of force on the controls to keep the nose down. The plane can stall if the pilot is unaware and fails to catch the pitch change.
Prevent trim stalls by being prepared–keep your hand on the controls during power changes and positively fly the aircraft based on its attitude.
In VFR flying, this means keeping the proper sight picture when transitioning from the descent into the go-around climb. Then, hold the plane in the right attitude, and start re-trimming it for the climb out to relieve the control pressure.
Check out Chapter 5 of the FAA’s Airplane Flying Handbook for more details about these stalls.
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Brian is an experienced digital marketer who joined Thrust Flight in 2022 as the Chief Marketing Officer. He discovered a passion for aviation at 10 when he went for his first flight in a Piper Cherokee and enjoys helping others discover a career path as a professional pilot. He is an experienced marketing consultant helping brands with a variety of marketing initiatives. Brian received a bachelor’s degree in Communications from Brigham Young University.