Do you know what happens during a stall? Contrary to common belief, it doesn’t involve mechanical failure. While stalls typically result in a loss of altitude, they don’t involve the failure or engines or other mechanical components. To learn more about the science behind stalls, keep reading.
What Is a Stall?
When used in the context of aircraft, the term “stall” refers to a phenomenon in which an airplane no longer produces a sufficient amount of lift. It’s typically the result of an excessively high angle of attack. If an airplane’s angle of attack becomes too high or steep, it may no longer produce enough lift to maintain flight level. As a result, the airplane will experience a stall while subsequently losing altitude.
What Happens During a Stall
Airplanes produce lift — a force that allows them to stay in the air — via the pressure difference between the air moving over and under their wings. The pressure of the air moving under an airplane’s wings is greater than that of the air moving over its wings. This pressure differential literally lifts the airplane and allows it to overcome gravity. A steep angle of attack, however, can result in a loss of lift — so much that the airplane loses altitude.
Stalls are characterized by an insufficient amount of lift. They are mostly caused by a steep angle of attack, which is the angle between the chord of an airplane’s wings and the surrounding wind. As the angle of attack increases, air may no longer flow smoothly over and under the wings. Instead, air will break away, resulting in insufficient lift and the phenomenon known as a stall.
When an airplane stalls, the following may occur:
- The nose of the airplane will begin to drop.
- The airplane’s speed will decrease.
- One of the airplane’s wings may begin to drop, followed by the other wing
- The airplane will lose altitude.
What Causes Stalls
Stalls generally occur when an airplane’s angle of attack is too steep. Climbing at a steep angle after takeoff, for instance, can cause an airplane to stall. Making a sharp turn on the final approach can also cause an airplane to stall. Pulling the nose up too aggressively during flight can also result in a stall.
How Pilots Recover From Stalls
Fortunately, most pilots know how to identify and recover from stalls. Stall recovery typically involves decreasing the airplane’s angle of attack. Lowering the nose, increasing the airplane’s power/speed and leveling the wings will often correct the angle of attack. And upon correction, the airplane will once against have sufficient lift to keep it in the air.
