By WILLIAM DRURY
During a recent aviation training seminar led by G Dale, author of the gliding textbook “The Soaring Engine,” he drew a diagram familiar to all students of aviation: The standard Angle of Attack vs. Lift curve.
The curve demonstrates that as the angle of attack of a wing increases (along the x-axis), the amount of lift produced by the wing (along the y-axis) also increases until a point is reached where air can no longer flow smoothly along the wing (point S on the figure below).
This disrupted airflow causes the amount of lift to dramatically decrease and we say that the wing has “stalled.”
This concept applies to all lifting surfaces, even if the slope of the line and the suddenness of the drop-off vary among different airfoil designs.
Then he challenged everyone’s thinking: He wasn’t drawing a graph of wing performance. He was plotting the relationship between levels of stress (x-axis) and pilot performance (y-axis).
Stress and The Pilot
There is a distinct relationship between the amount of stress experienced by a pilot and the pilot’s ability to perform the many tasks required to competently fly an airplane.
At first, a slight increase in tension leads to increased concentration, better physical dexterity, and more complete situational awareness. Simply put, your flying performance improves.
As the amount of stress increases, however, the pilot eventually becomes overwhelmed and unable to perform even relatively simple mental and physical activities. The pilot’s level of performance suddenly falls off, just as the amount of lift dramatically decreases when a wing exceeds its critical angle of attack.
Starting at the lower left portion of the curve, imagine yourself in a very relaxed scenario: Perhaps you are flying a familiar aircraft on a pleasant day at your local airport, with some sightseeing in mind. As you climb out, you are comfortable and enjoying the ride. Maybe you don’t focus too hard on rudder coordination, bank angle, and airspeed, but as long as you are reasonably competent you are able to fly safely. Low stress, adequate performance.
Now think about a situation where your anxiety increases, such as during a check ride or flying a new aircraft for the first time.
You may feel a bit more alert, pay more attention to what the plane and its instruments are telling you, and have less tolerance for any sloppiness in your flying. Because of this increased focus your overall flying performance is improved. Medium stress, better performance.
Moving the tension level somewhat higher, consider a cross-country trip far from home. Such a flight could bring new challenges, including changes in weather, complex communications with ATC, and navigation over unfamiliar territory.
Now you are paying closer attention to every sound the engine makes, keeping a better lookout for traffic, double checking your position, and carefully monitoring the fuel gauges. Many pilots find that these flights bring out the best in their piloting skills, which makes them the most satisfying.
For experienced pilots this may represent the highest point along the “Stress-Performance” curve.
Any additional challenge, however, may move a pilot along the curve past the peak of performance into a region of rapidly decreasing decision-making capability and physical coordination. This condition is analogous to that portion of the Angle of Attack-Lift curve beyond the point of the wing stalling.
This could occur when a pilot is at or near the top of their individual performance curve and then one more stressor is added. It could be a sudden change in the weather, an instrument failure, or a rough-running engine. Just when judgment and flying skills are needed most, the simplest task becomes impossible and mental focus and physical skills degrade. We can say the pilot’s brain has “stalled.”
While the graph is a good generalization, it is important to understand that your curve is different from that of everyone else’s. Some people have a very steep curve, so that just a small amount of increased anxiety shifts the pilot “up and to the right” towards — or even past — the Brain Stall point. Others have a flatter curve and can maintain nearly peak performance under a wide variety of stress levels.
We all know people who are able to remain calm under conditions that would rattle the average person. On the other hand, most of us know people who cannot keep it together under what appears to us the mildest of pressures.
Why Do Brain Stalls Happen?
The reasons for brain stalls lie in the realms of biology, anatomy, and evolution.
A look at the anatomy of humans as compared to other mammals reveals that we possess a larger and more developed part of the brain known as the pre-frontal cortex. This is involved in a variety of advanced mental tasks, including learning, focus, short-term memory, and speech.
It also is home to our executive function, which allows us to sift through a number of memories, potential behaviors, and imagined scenarios to choose an action appropriate for a challenging situation — exactly the kind of higher-level thinking that pilots need to be doing throughout a flight, especially during those times when things are not going as well as we would like.
Unfortunately, this portion of our brains is quite susceptible to the effects of subjectively perceived stress.
Initially, as we transition from a relaxed and anxiety-free state to a situation with a small amount of tension, this part of the brain becomes more active. Memory is sharpened, decision-making is faster and more rational. Physical coordination is improved. A little stress is good.
However, when a pilot’s anxiety level exceeds the limitations of their personal Stress-Performance curve, the executive function shuts down. This has the effect of decreasing the pilot’s ability to recall, evaluate, and perform actions required to successfully manage a challenging situation.
Luckily we have a backup system when a brain stall is imminent.
Calling on portions of the brain that are evolutionarily older, signals go out to the rest of our body to maximize our chances for survival. Adrenaline and other hormones are secreted into the blood stream. Heart rate, blood pressure, and respiratory rates go up. Blood flow is shunted from the digestive tract to our muscles. Pupils dilate. Our brain has decided that the time for reasoned decision-making has passed and is now getting ready for immediate and possibly violent action. Our bodies are being prepared for physical combat or rapid retreat from a dangerous situation.
While this is commonly known as the Fight or Flight Response, the flight portion of that label refers to running from danger, not piloting an aircraft.
Preventing Brain Stall
Fortunately there are some factors that we can control that may help us shift “down and to the left” along our personal curve so that we continue to use all of our mental faculties.
Obviously the best strategies are those that prevent as many in-flight stressors as possible. The lower on the curve you start, the more tolerance for stress you will have before reaching brain stall.
Preparing the body
One of the most important factors for preventing build-up of stress is attention to physical comfort. If you are uncomfortable, or in pain, you are being pushed up and to the right along the curve.
For example, trying to fly an unfamiliar approach while desperately needing to urinate becomes more and more difficult as your bladder approaches critical mass. If you are flying out of the landing pattern, and especially if you are attempting a cross-country flight, install and be prepared to use some kind of urinary relief system.
Likewise the potential challenges of hunger, thirst, and hypothermia can all be managed with minimal effort before the takeoff roll begins. Take care of your body to keep your brain working.
Preparing the mind
A feeling of being well-prepared, confident, and in control tends to flatten a pilot’s curve.
Factors that contribute to this state include:
- Familiarity: Flying an airplane that you know (or have been well briefed about), from an airfield you have studied, on a flight that has been thoroughly planned will minimize a fear of the unknown that could push you up the curve. Stay current.
- Checklists: Carefully using checklists with intention and without distractions will pay dividends in confidence. Higher levels of confidence are correlated with better physical performance and improved stress tolerance. This will allow you a clearer focus on airmanship, traffic, and weather. In addition, memorization of short emergency checklists for foreseeable high-stress conditions can help keep you mentally balanced and increase your ability to function rationally.
- Pre-Visualization: It is a useful practice to imagine unusual in-flight conditions and emergencies and then run through the appropriate actions while in the comfort of your easy chair at home (or actually sitting in your airplane on the ground). This practice will make those situations more familiar to you. Familiarity decreases stress.
It is possible to recognize when a brain stall is approaching.
Physical symptoms may include nausea, rapid breathing, sweating, shaking of the hands, and loss of physical coordination.
Mentally, a sense of impending doom may replace optimism. Attention may become scattered as you glance rapidly around the sky and hurriedly scan your instruments without having any memory of what you have just seen.
Conversely, in some situations your vision may tunnel in on one intimidating object to the exclusion of all other potential hazards. This can happen in a busy landing pattern as your attention is locked onto a single nearby aircraft and your ability to perform normal pre-landing tasks is degraded.
Recovery
Sometimes just the recognition of an impending brain stall can allow you to blunt its impact.
This is the time to take action to keep your higher functions online:
- Control your breathing. Deep, slow breaths can have a calming effect.
- Repeat a familiar phrase that helps to direct your activities. Many instructors use the phrase “Just Fly the Airplane” when teaching students to manage tense situations. Saying the words out loud in the cockpit may help you refocus on the basics of stick and rudder flying and proper scanning techniques.
- Mentally review any appropriate checklists and, if time permits, refer to the actual written version for confirmation.
- Create positive thoughts. Brain stall can lead to pessimism and a sense of hopelessness. Phrases such “You can do this” or “I’ve done this before” spoken out loud may allow a pilot to maintain the ability to understand a complex situation and evaluate potential solutions.
By now you may have realized that brain stall does not just happen while flying airplanes. It is a reaction that occurs whenever an individual feels overwhelmed by stress. It can occur if your car skids out of control on a wet road. It may even be precipitated by heated political arguments. In most cases the outcome will be improved if we keep the logical and more rational parts of our brain functioning.
While there are occasionally situations for which the Fight or Flight Response is advantageous, safe airmanship requires access to our complete range of mental abilities.
Keep both your wing and your brain flying!
The author lost credibility for me when he began to talk about evolution. Approaching any subject with an evolutionary worldview is likely to result in incorrect conclusions. Fortunately, in this case, that was not a problem.
Very good presentation. Perhaps the most dramatic illustration of a mental “lock up” is when a student pilot freaks out in a practice spin and locks up the controls with muscles that at 5x their normal strength as all the adrenalin freezes them. The CFI then has to physically whack the student to unlock their brain. This also can be seen in police chase scenarios when police have chased someone they perceived as a threat and at the end of the chase the officer loses control of their rational brain. What happens in these situations is that the most primitive part of the brain, the cerebellum, a/k/a the “reptile” brain hijacks the prefrontal brain. Both of these brain areas perform “executive” functions but do so differently.
The reptile brain is mostly involved in making “yes or no” reactive decisions. Fight, flee, or lock up. Our flying brain cannot use this type of decision-making in most situations because all of the many factors involved in making the correct or safe aeronautical decisions are not on the table in fight or flee. The brain decision is far below rational thought. The core thought at this level is “I am going to die, what should I do?” If this thought cannot be interrupted, the pilot will freeze and probably make the wrong decision e.g., pulling back on the elevator instead of pushing forward as the aircraft enters a stall.
In contrast, our pre-frontal brain is a logical brain that uses both deductive and inductive logic. For piloting, we mostly use the deductive aspect of our reasoning ability. If A and B are true, then C is the correct conclusion. e.g. “I know the aircraft stalls at 40, I am flying at 45, I must not let my speed degrade further, so I need to keep the nose down.”
In the panic situation, the deductive logic is short-circuited by the cerebellum’s reptile and the decision (irrational) becomes: “The ground is approaching, hitting the ground is a threat, I will die if I don’t avoid the threat, therefore I must pull back on the stick with all my strength to avoid the threat.” This is the sequence of the panic reaction. This is a reaction sequence that is below our conscious mind. It is reactive and “instinctual”.
The article has many good pointers on how to manage inputs to keep the reptile brain in check. Breathing is a key point. Most of us in our daily lives ignore our breathing. In all extreme tension situations, (I think 100%), what happens is the person stops breathing. We can see this in “stage fright”, where a person cannot talk due to their fear. They can’t talk because they either are not breathing or are hyper-ventilating – both alter brain chemistry and thought. Think about this for a second. One of the most fundamental and the most immediate requirement for life is our ability to breathe. When our stress locks up our breathing, it sends a very clear signal to the cerebellum that there is a fundamental threat to our existence, and the cerebellum wakes up. If the stress and impaired breathing continue, the cerebellum takes over and makes the fight, flee, or lock-up decision. The cerebellum disengages the pre-frontal, deductive logic brain because the cerebellum is what controls the fundamentals of life – breathing, hunger, sex, fear, fighting, fleeing, etc. When the cerebellum is in control, we can forget making rational decisions.
So, how do we deal with this very natural phenomena of the “locked up brain”. Brain training. Learning to control our brain at all levels, including most importantly, learning to control our breathing. This attention to breathing is critical to learning stress-free reactions and behaviors in the flight environment. We cannot learn breathing control without being aware of our breathing. It is not possible. How do we accomplish conscious breathing? Practice. Practice conscious breathing when stress free and practice when under stress. That gives us control. The method? It is simple.
Practice When not stressed:
Try this and see for yourself: First Step in getting control and recognition that we are not in control: Sit or lay down with eyes open, and consciously direct the mind to breathing. Consciously ignore whatever you are seeing by not forming any thought about that. Instead, as the wandering brain begins to form thoughts, recognize that it has happened. you have lost control of your thinking at that point. Bring your brain back to concentrating on only the physical breathing. (This is your pre-frontal brain trying to control your cerebellum, which is controlling your breathing). Initially, a person cannot consciously focus on their breathing for more than 5 seconds, or less. What happens is as soon as we think about controlling the air going into our lungs, our stress brain will hijack our thought and will switch to some other focus; e.g., “What was the phone call I needed to make? What is that itch? Did I feed the dogs today? The Plane needs new tires? Did I pay the hangar rent? Do I have any new texts” etc, etc. Anything but breathing. So, what do we do when we realize we have lost control? We train the brain to do what we want it to do- think about our breathing and just that.
How to do it:
Immediately recognize that the brain has chosen its own thought priorities instead of staying focused on what we have directed it to do, our Focus on breathing. Just recognize that fact. Recognize the brain wandered off to do its own thing. No big deal. And then, immediately refocus the brain on what we want it to think about: the physical aspect of breathing. Air going in, chest rising, lungs filling, then holding it, then slowly releasing it. As we are learning to consciously breathe, we also pay attention to the stress in our body, because it will almost always be stressed to some degree or the other. So, as we breathe in and out slowly, we consciously recognize stress in our muscles and we consciously relax our entire body. The conscious activity of breathing and relaxing releases stress. By releasing stress, we regain control over our brain. We are in charge. The more we practice, the more we are able to recognize stress and prevent that stress from activating our cerebellum’s bad decision-making that can kill us. This is a great way to begin and end each day, with breaks during our day. It will lower your blood pressure and will allow you to make better, relaxed decisions about everything.
Practice When stressed:
So, what does this have to do with dealing with stress in training and flying? Again, it is brain control through recognition of stress and breathing. Every pilot who has crashed in panic is a pilot who was locked up by stress and was not breathing. The safest way to practice control of this stress reaction is in a flight simulator. Make a list of all the possible stressors you might encounter in a flight and program those into the simulator. Have the simulator “spring” them on you. Recognize your breathing, pay attention to it by conscious breathing during the situation. Practice a controlled, mindful breathing response to the stress. If you cannot control your breathing and your reactions to the stressors 100%, you should not fly until you can. Why? Because that stressor you cannot control may arise and you will be subject to your out of control cerebellum. I think this is a must for teaching students. Why risk putting a student into a novel stress situation when their reaction may be a lock up that kills everyone onboard? That is foolish. Put the student in the situation on the ground and monitor the student’s reactions by making them think about their breathing and reaction to the stress. If they can’t breathe, if they are not 100% relaxed, they can’t safely fly. We want to load up the stress and then unload it consciously on the ground. Visualize the situation, the stress, the reactions, the breathing, and then unloading the stress through proper controlled response, breathing, and tension release. As we do that, we are engaging the conscious mind. We are putting our conscious brain in control. I can still remember my student training when the CFI reached over a tapped my arm as I clenched the wheel. “Relax”. He could see my tension. I was unaware.
Flight simulators can be rented. There are some new manufacturers that make relatively affordable units for the home or office. Considering the cost of a botched landing, take off, or stall and fall, they are worth the investment of time and money. If that is out of the question, then practice active visualizations of each stressor and/or your reaction, and your breathing during the situation. Simulation and conscious training are the ultimate bacon savers. Even the most experienced pilots have patches of stress in their lives and training that can affect their flying decision-making. If you have new stressors in your life, consciously deal with them on the ground before starting the engine. Or stay home until you are in control.
Safe flying, blue skies, and Happy Fourth!
My dad was an old military WWII combat pilot and world record flyer… and was ‘forever’ [+40-years] a broad spectrum CFI who was also MY CFI. Combat made him necessarily a ‘defensive-pilot’.
In addition/complement to what You said…
Dad emphasized [hammered-in] several aspects that I have taken to heart… even as an aero engineer…
What You are describing is… in old-fashion terms… is “Task Saturation”. A creeping or sudden loading of several small-to-large elements to saturate and ‘lock-up’ the decision making [responsiveness] capability. In engineering terms: “analysis paralysis”.
Never fly tired or sick… mentally/emotionally or physically or socially… unless mission critical… then be extra wary of trouble. These conditions degrade ability to absorb and perform tasks.
Get-home’itis is sickness and not mission critical call the wife and speak truth to ‘stop’.
Never lie to Yourself about the condition of ‘You’, Your ‘passengers’, the ‘aircraft’, the ‘flight-to-come’ [terrain, traffic, weather, etc]. Everything should be fit-to-fly.
‘Listen’ to Your aircraft with your subconscious eyes, ears and body. It will speak the truth when attention is diverted outside.
IF you are intent to really do something of ‘high danger’, never imperil anyone else by a risky spontaneous/unplanned, or ‘for-thrills’, action. The ‘thrill of victory’ is self satisfaction/pride and another lesson learned; HOWEVER, the highest price for failure does NOT need to be paid by anyone else but You [IE: me].
I like the “mission creep” aspect. Task saturation. The little things creep up on the pilot until suddenly, it’s an avalanche. Remember, one pilot’s speed bump is another’s avalanche. It would be good to practice that with conscious intent. Try to get to your “max-out”. Realize it is happening. Breathe, relax. Concentrate on flying the airplane by elevating that thought above all others. Fly it with whatever part of the aircraft that is working, but always, that is first. Dan Gryder talks about this when he was flying a little Cessna 150 and had a flap malfunction in a go around. Had intense struggle resisting pulling back on the yoke. Nearly overwhelming. Training prevailed. Just shucked some corn.
While I am not instrument rated, it baffles me how VFR pilots with an artificial horizon and other basic instruments cannot manage to fly out of inadvertent IMC encounters. Seldom do we learn from those pilots. My thought is that the pilot panics and locks onto something other than flying the airplane using the panel. Relaxing and flying the panel is always the way out as we know. Learn to demote every non-essential thought that has crept in to overwhelm and saturate our conscious mind’s training. Use only the input that is necessary to support the central mission. That will de-saturate.