Airplane Stall Avoidance

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To learn to avoid stalls and be able to recognize them instinctively, you must first be very familiar with stalls. That is precisely the reason we have spent so much time discussing the various types of stalls you might encounter: normal, accelerated, approach, and departure are all stalls that you should be very comfortable with. Once you can enter and recover from these stalls, and as you practice each of these maneuvers, you gain a feel for them. This feel, the ability to know what the stalls make the plane’s control surfaces feel like, the attitudes and sounds of the engine, and slipstream are the core of being able to recognize the onset of a potential stall. Through practice you can not only get better at entry and recovery from stalls, but you also gain the insight to know when the airplane is about to stall, without looking at the instruments. This knowledge is crucial to avoiding stalls when situations become critical. So go out and practice stalls as often as you can; it will help you become more proficient at stall avoidance as well.

As you are practicing, what should you be paying attention to that can help in learning stall avoidance? There are a number of warning signs, many of which we have already covered. The flight instruments can provide a great deal of information via the airspeed indicator and the turn and bank indicator. If you notice the airspeed indicator dropping toward the bottom of the green arc, you know the airplane is becoming a little too slow. If the artificial horizon shows an abnormally large pitch, it might be a good idea to check the airspeed and verify that you are not bleeding off too much airspeed.

Most stalls are not caused when the pilot is closely monitoring the instruments, though. It is not possible to document each potential accidental stall scenario, but some common factors should be considered important. Often the pilot is distracted in one way or another and does not pay attention to the plane. This distraction can come in the form of trying to force the plane into a steep bank as the pilot attempts to avoid overshooting the turn from base to final. The pilot can become so focused on the turn that he or she loses focus on how steep the bank is in relation to the speed of the plane. An accelerated stall can have very rapid onset, with little time between prestall buffet and the actual stall, making it more difficult to recover once the stalls become imminent. For these reasons it is very important to avoid accelerated stall situations, especially when flying in the pattern. Do not focus so heavily on one aspect of the flight that you ignore other pieces. Keep a broad view of what is going on; get into the habit of being “situationally aware” as you fly.

Avoid distractions while maneuvering at low speed. Some of these may include radio chatter or Air Traffic Control, looking at an approach chart or sectional, a passenger asking you questions as you get ready to land, or any number of other things that can pop up during a flight. Emergencies are a great way to become distracted. An engine that suddenly begins to run rough and loses power can cause you to focus almost exclusively on the oil and fuel pressure gauges if you don’t make yourself stay aware of the entire situation. Gear lights not showing green as you get ready to land can also be a situation that might have you looking at the lights, head buried in the cockpit. In a case like this you are already slow, head looking down at the gear indicator lights, and if you lean forward to tap on them, you may unknowingly pull back on the control yoke as a brace.

Pay attention to the feel of the controls. If you have your head in the cockpit, you should still be able to notice when the controls become softer due to dropping airspeeds. This is a definite indicator that you are getting slower than you want to, especially if you are in the pattern or at low altitudes.

Sounds are another major sensory input that can help you maintain situational awareness. As the plane slows, the sounds generated by the slipstream will become quieter. Like the feel of the controls, you do not need to be looking outside the plane to notice this change in sound levels. Conversely, if the plane is picking up speed, the noise of the slipstream will increase. Engine noises will also change with changes in airspeed, and any difference in sounds from the engine can also be an indicator that your airspeed is changing either up or down. With practice you can become fairly accurate at “guesstimating” the airspeed based on the sounds of the plane.

On takeoff you should be familiar with the normal pitch attitude used to achieve airspeeds such as Vx and Vy. If you notice that the nose is higher than normal during takeoff, you should verify your airspeed. In some cases this pitch angle/airspeed difference can be caused by improper use of flaps, the gear being down/up when it should be in the opposite position, or improper propeller or engine power settings. Obviously you will need to be looking outside the plane to notice excessive or shallow pitch attitude, but this can be a clue that other factors are affecting the performance of the plane. High angles of attack can lead to low-altitude stalls, so be very careful.

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