Vectors For Safety

Vectors For Safety - July 2026

June 30, 2026

July is All About Heat

This month we are focusing on heat. More specifically, on how flying in hot ambient temperatures can affect our human performance as well as the performance of our airplanes. Gene's Blog and our cognitive science article both address the subject. Also, we have added three related videos to our Essential Vectors Series. Find them plus a "fan favorite" in our Videos Section. (Note: Scroll down to the Essential Vectors section.) Plus we have added a new Old Pilot Tips video titled "Hydration." (See below for that link.)

New Episode of Our Old Pilot Tips Series is Available

This Episode 43 of our “Old Pilot Tips” series reminds us of the importance of hydration. This 58-second video illustrates some of the negative early effects and early warning signs of dehydration and provides some valuable tips on how to achieve and maintain adequate hydration for our flights. The video is simply titled, “Hydration” and is sponsored by Avemco. Check it out here.

Highly Recommended Issue of "NASA Callback"

A very appropriate issue of "NASA Callback" has been released. "Expect the Unexpected" applies to all segments of aviation. Check out Issue 557 here.

Recommended Course: "The Psychology of Approach and Landing"

Takeoffs are optional but landings are mandatory. But the majority of general aviation mishaps occur during approach and landing. Check out "The Psychology of Approach and Landing." Be safer and earn Wings credit too! Click here to visit the course provided free courtesy of Avemco Insurance.

Flying a small general aviation aircraft is already an exercise in constant multitasking, where attention, coordination, and decision-making must all operate at a high level. Add high ambient temperatures into the mix, and the brain begins to behave less like a finely tuned flight computer and more like an overheated device struggling to maintain basic function. In prolonged conditions above 90°F, especially over the course of a two-hour flight, the effects on both the body and mind become difficult to ignore—and more importantly, difficult to compensate for.
As temperatures rise, the body shifts into cooling mode, and that comes at a cost. The hypothalamus, responsible for regulating temperature, ramps up activity, triggering sweating and increased heart rate. At the same time, blood flow is redirected toward the skin to dissipate heat, which can slightly reduce cerebral blood flow to the brain. What this means for a pilot is subtle but significant: the brain is still working, but it is doing so with fewer resources. The energy that would normally support complex thinking is partially diverted to basic survival.
This shift creates what could be described as a “resource conflict.” The prefrontal cortex, the area responsible for higher-order thinking such as planning, decision-making, and prioritization, effectively gets taxed. Tasks that normally feel straightforward—radio communication, navigation decisions, checklist management—require more effort and may take longer to execute. Over time, this increased workload contributes to fatigue, even if the pilot doesn’t immediately recognize it.
Heat also disrupts the brain’s chemical balance. Neurotransmitters like dopamine and serotonin, which play a role in mood, focus, and judgment, can fluctuate under heat stress. This can lead to irritability or a subtle shift in risk tolerance—sometimes described informally as “get-there-itis,” where a pilot becomes more focused on completing the flight than maintaining optimal safety margins. At the same time, excess levels of glutamate, an excitatory neurotransmitter, can build up, contributing to the familiar sensation of “brain fog” and reduced mental clarity.
Another less obvious effect involves the brain’s protective filter, known as the blood-brain barrier. Under significant heat stress, research suggests this barrier can become more permeable, allowing inflammatory substances to enter brain tissue. While this isn’t something a pilot can directly perceive, it helps explain why extended heat exposure can create a heavy, sluggish mental feeling that goes beyond simple tiredness.
In the cockpit, these physiological and neurological changes translate into specific performance issues. Working memory begins to falter, making it easier to forget assigned altitudes or transponder codes. Attention becomes narrower, increasing the likelihood of fixation on a single instrument while missing other important cues. Reaction times slow, which can affect the precision of control inputs during turbulence or crosswind corrections. Even spatial awareness can degrade, making it harder for the brain to reconcile visual inputs with inner-ear balance signals. Each of these issues on its own may seem minor, but together they can significantly increase risk, especially during high-workload phases like approach and landing.
Layered over all of this is dehydration, which often accompanies heat exposure and amplifies its effects. Even a modest loss of body water—around 2%—can lead to measurable changes in brain structure, including slight shrinkage of gray matter and expansion of ventricles. These physical changes slow neural signaling, reducing processing speed and reaction time. By the time a pilot feels thirsty, cognitive performance may already be noticeably impaired.
What makes this particularly challenging is how gradual the process can be. A flight that begins in mild discomfort can, over the course of two hours, evolve into a state of cumulative fatigue and reduced mental sharpness. The pilot may not notice a clear tipping point—just a steady decline in ease, focus, and responsiveness. This “quiet degradation” is often more dangerous than obvious symptoms because it can go unrecognized until performance has already dropped.
In practical terms, the biggest risk isn’t necessarily dramatic heat illness but the erosion of the very skills pilots rely on most: attention management, disciplined procedure following, and sound judgment under pressure. Small lapses—missing a checklist step, reacting a bit too slowly, or overlooking a subtle cue—become more likely as heat stress builds.
Ultimately, flying in high temperatures is as much a cognitive challenge as it is a physical one. The body’s efforts to stay cool come at the expense of mental performance, and over time, that tradeoff becomes increasingly significant. Recognizing that connection is key. When the cockpit starts to feel uncomfortably warm, it’s not just a matter of comfort—it’s an early signal that performance may already be affected.
Staying ahead of those effects requires awareness and proactive management, but it begins with understanding that heat is not just an environmental factor—it’s a physiological stressor that directly influences how a pilot thinks, reacts, and flies.

Want to learn more about cognitive science as it relates to the general aviation pilot? Check out our "Squawking Human" feature!

Keeping Cool Aloft: Managing Heat Stress in the Summer Sky
As the summer sun settles in and temperatures climb, flying can take on a whole new kind of challenge—one that’s easy to underestimate. It’s not just about sweating it out in a warm cockpit. The real story begins well before takeoff, during those ramp activities like pulling the airplane out, fueling up, running through a preflight, and loading baggage. By the time we’re strapped in and ready to go, our bodies may already be working harder than we realize.
What’s happening behind the scenes is worth paying attention to. When we’re exposed to heat, our bodies start working overtime to keep things stable. Sweating helps cool us down, but it also drains fluids. Meanwhile, heart rates tick up as the body tries to move heat away from vital areas. Over time—especially on longer flights—this adds up. Tasks that normally feel routine can begin to feel just a bit more demanding, and that subtle shift can creep in faster than we’d expect.
The tricky part is that the early warning signs don’t always scream for attention. We might notice we’re a little thirstier than usual, maybe dealing with a dull headache, or feeling slightly fatigued or lightheaded. Sometimes it shows up as difficulty concentrating—that fuzzy “brain fog” feeling. These aren’t dramatic symptoms, but they’re the body’s way of signaling that it’s under stress. If we let them go too long, they can escalate into something more serious, like heat exhaustion, bringing nausea, rapid breathing, or even fainting into the picture.
For pilots, even mild symptoms matter. Heat doesn’t just affect comfort—it can chip away at performance. Things like coordination, reaction time, and decision-making can all take a hit. We might find ourselves rechecking a checklist more than usual, scanning less effectively, or reacting a bit slower than normal. These small changes can become especially critical during high-workload phases like approach and landing, where precision and timing are everything.
One of the biggest misconceptions is relying on thirst as a guide. By the time we feel thirsty, dehydration may already be setting in enough to affect performance. Add in factors like direct sunlight, limited airflow in the cockpit, and even what we’re wearing, and it’s easy to see how a “slightly warm” start can turn into noticeable fatigue by the end of a flight.
It helps to stay alert for subtle in-flight cues. Increasing irritability, slower thinking, or having to reread checklist items can all be signs that heat is starting to interfere. Feeling lightheaded during maneuvers or developing a headache while sweating more than usual are also worth paying attention to. If symptoms escalate to nausea or confusion, that’s a strong signal that the situation needs immediate attention—reducing workload and reassessing the plan becomes essential.
The biggest takeaway here is that heat is often a gradual threat. It doesn’t arrive with flashing lights or obvious alarms. Instead, it quietly wears down performance over time. That’s what makes it so important for all of us to recognize the signs early and stay proactive.
At the end of the day, staying safe in the summer heat comes down to awareness and preparation. Understanding how our bodies respond, keeping hydrated, and checking in with how we feel throughout a flight can make all the difference. Because when it comes to flying, staying cool isn’t just about comfort—it’s about staying sharp where it matters most.

Accidents discussed in this section are presented in the hope that pilots can learn from the misfortune of others and perhaps avoid an accident. It is easy to read an accident report and dismiss the cause as carelessness or as a dumb mistake. But let's remember that the accident pilot did not get up in the morning and say, "Gee, I think I'll go have an accident today." Nearly all pilots believe that they are safe. Honest introspection frequently reveals that on some occasion, we might have traveled down that same accident path.

Doing ERA25FA201 filed under accidents/Heat Effects-pilot

This fatal crash happened in Florida in May of 2025 and involved a PA32RT. The 56-year-old, 378-hour private pilot died in the crash while his wife waited for him at the destination airport. The NTSB report includes the following: "The pilot’s spouse reported that the purpose of the flight was for the pilot to reposition the airplane from Nassau Airport (83FL), Yulee, Florida, to Fernandina Beach Municipal Airport (FHB), Fernandina Beach, Florida, where they would wait for approaching thunderstorms to pass through the area before continuing on to Tennessee. She reported that, earlier in the morning, the pilot had dropped her and their dogs off at FHB by ground vehicle before driving back to 83FL, where he planned to finish loading the airplane for their trip and make the short flight to FHB. The straight-line distance between 83FL and FHB was 3.9 nm."

The NTSB report continues, "Review of video captured by a motion-activated surveillance camera mounted on a hangar near the end of runway 12 at 83FL showed that the airplane taxied toward runway 12 and began a back-taxi down the runway and out of the video frame (figure 1). During the taxi the airplane’s nose baggage door appeared closed. As the video continued, the airplane re-entered the frame on a takeoff roll about 0934. The video showed that, during the takeoff, the nose baggage door was open. The door stayed open while the airplane became airborne and exited the video frame. Following the accident, a sweep of the usable portion of runway 12 found a case of aviation oil about 100 ft from the beginning of the runway and to the right of the centerline. A bag of dog food was also found about 440 ft from the beginning of the runway and to the right of the centerline. Review of surveillance video showed the airplane in a nose high angle of attack just after lifting off. One eyewitness reported that the wings rocked back and forth before the left wing of the airplane dropped and the airplane descended behind trees. Another witness and surveillance videos showed the airplane enter a steep left-wing-low descent just before impacting a tree and the ground about 10 seconds after departing 83FL."

NTSB Graphic

The NTSB report also includes: "Witnesses described that it had just begun to rain about the time of the accident. A review of meteorological conditions showed that at the time of the accident there were thunderstorms quickly moving toward the area. It is not likely that the airplane encountered a weather phenomenon that would have jeopardized the safety of the flight, because the storms were not directly over the accident area at the time of the accident. However, the approaching thunderstorms likely resulted in external pressures and the pilot experiencing “get-there-itis” and rushing to depart on the short flight. It is also likely that, in his rush to depart, the pilot did not ensure the nose baggage door was securely latched, which resulted in the door opening Page 1 of 12 during the takeoff roll. The pilot’s distraction during a critical phase of flight likely resulted in the airplane’s nose-high pitch attitude, exceedance of the critical angle of attack, and subsequent stall/spin."

NTSB Photo

And the NTSB report continues: "Two individuals reported that the pilot posted a Snapchat video shortly before the accident. The Snapchat video reportedly depicted the terrain ahead of the airplane while it was 5 to 10 miles southeast of the accident site. Although the video was automatically deleted from the Snapchat platform 24 hours after the accident, it reportedly did not include the final moments of the flight. One of the individuals provided a screenshot of the Snapchat application’s map that showed the approximate location of where the pilot posted the video. When compared to the airplane’s recorded radar ground track, the location of the pilot’s Snapchat post was about 1.5 miles southeast of the radio tower, and likely was posted about 35 seconds before the accident. The airplane’s ground track was already left of the pipeline when the pilot posted the Snapchat video. Based on the known information, it is likely the pilot was distracted while he used his mobile device in the minutes before the accident and did not maintain an adequate visual lookout to ensure a safe flight path to avoid the radio tower and its guy wires."

NTAB Photo

The NTSB probable cause states, "The pilot’s exceedance of the airplane’s critical angle of attack during takeoff, which resulted in a stall/spin at an altitude too low for recovery. Contributing to the accident was the opening of the nose baggage door and subsequent distraction of the pilot during a critical phase of flight, as well as the external pressure of the approaching thunderstorms, which likely resulted in the pilot rushing to depart."

NTSB Photo

Many factors likely contributed to this crash. The NTSB could not determine the pilot's flight currency, but a lack of proficiency may have been a contributing factor. The open baggage door certainly created a major distraction. The pilot was likely hurrying to get airborne to beat the approaching weather so perhaps he did not verify that the baggage door was securely latched.

But in line with our topic this month, the pilot was operating with the ambient temperature of 77 degrees F. and relative humidity of 74%. The NTSB report states that the pilot had dropped off his wife and their dogs at FHB and drove to 83FL to load the airplane for a trip to Tennessee. The accident flight was a repositioning flight to pick up his wife and the dogs at FHB. A post-crash sweep of the runway at 83FL recovered a case of engine oil and a bag of dog food, presumably from the unlatched baggage compartment. Prior to takeoff, the pilot presumably had loaded these items, along with baggage and other items for the trip to Tennessee. He likely had loaded the car with these items before departing for FHB. While the temperature and humidity would not be considered dangerous in isolation, we should consider that the pilot may have been operating on a hot driveway and hot airport ramp where the temperature may have been several degrees warmer. Then considering that the pilot was hurrying to beat approaching weather, the possibility of degraded cognitive and physical function due to heat effects is a possibility.

Click here to download the accident report from the NTSB website.

NTSB Photo (Actual Accident Airplane)

This crash took the life of the 73-year-old, 18,000-hour ATP. The crash occurred in Louisiana in May of 2021. The crash involved a Sub Sonex JSX-2 small turbojet powered light sport airplane.

The NTSB accident report includes the following: "Automatic dependent surveillance broadcast track data showed the airplane take off and shortly thereafter maneuver low-level over the lake until track data was lost. A witness reported that he and several others saw the airplane fly across the lake at an altitude of about 200 ft above the water. The witness reported that just before the accident he saw the airplane roll to the right until it was inverted and then it abruptly nosed down and impacted the water in a near vertical attitude. Another witness reported seeing the airplane performing a barrel roll over the lake during the previous week."

NTSB Graphic

The NTSB report continues: "The airplane's wreckage was recovered and examined. Airframe damage showed that the airplane impacted the water in a near-vertical, nose-low, right-wing-down attitude. Flight control continuity was confirmed, and the engine and engine control unit showed no preaccident malfunctions or failures that could have contributed to the accident."

NTSB Photo

The NTSB report also includes: "TToxicology testing showed the pilot had used the potentially impairing drugs sertraline, bupropion, quetiapine, gabapentin, and pramipexole. However, is not possible to reliably predict the combined effects of these drugs or how they affected any impairment from underlying medical conditions the pilot had. In addition, the small amount of ethanol detected may have been produced after the pilot’s death."

NTSB Photo

The NTSB probable cause states: "The pilot’s failure to maintain clearance with the water while performing aerobatics, resulting in the airplane’s impact into a lake. Contributing was the pilot’s decision to perform aerobatics at low altitude."

NTSB Photo

We cannot know to what, if any, extent the potentially impairing drugs had on the pilots cognitive or physiological abilities. We might also consider the possibility that heat effects may have played a role. The ambient temperature was 84 degrees F. The pilot was sitting under a canopy that appears to have been tinted but likely contributed to heating of the cockpit. Thinking back to the task load vs. capabilities graph, low level aerobatics certainly produces a high task load. If the medications reduced the pilot's capabilities the heat effects might have produced a further reduction causing the curves to momentarily cross.

In any case, low level aerobatics greatly increases risk which must be carefully weighed against whatever reward is to be gained.

Click here to download the accident report from the NTSB website.

This crash occurred in Louisiana in October of 2020. The airplane involved was a beech V35. The 73-year-old, 1570-hour private pilot died in the crash.

The NTSB accident report includes the following: "The pilot and flight instructor had just completed a one-hour uneventful local flight to test the recently repaired autopilot. The pilot landed the airplane, dropped off the instructor at the terminal, and then taxied away. Minutes later the airplane departed to the north, reached about 200 ft above the ground, and entered a left turn. The airplane subsequently descended into trees and terrain and a postimpact fire consumed most of the airplane. There were no witnesses to the accident, and about 4 hours after the accident smoke from the wreckage was reported by another pilot."

NTSB Photo

The NTSB report also includes: "Examination of the wreckage did not reveal any preimpact mechanical malfunctions or anomalies that would have precluded normal operation; the accident site was consistent with a steep, nose-low descent with the engine producing power."

NTSB Photo

The NTSB report further includes: "The medical investigation in this case revealed that the pilot had a history of significant coronary artery disease with stents and had used a sedating medication (cetirizine) at some time before the flight; however, whether the pilot’s heart condition or use of sedating medication contributed to the accident could not be determined based on the available information. The evidence at the accident site and the lack of mechanical anomalies are consistent with a loss of control during takeoff; however, the reason for the loss of control could not be determined."

The NTSB probable cause states: "The pilot’s loss of control shortly after departure for reasons that could not be determined based on the available information."

So, we will never know what happened in the last few seconds of the fatal flight. In addition to the medical history and medications used, we might consider the effect of heat on the pilot's cognitive and physiological capabilities. The ambient temperature is reported to have been 86 degrees F. with the relative humidity calculated to be 59%. The flight time for the two flights that day was more than one hour plus whatever time was spent on the ramp for preflight inspection We might consider the possibility of heat effects reducing the pilot's cognitive and physiological capabilities.

Click here to download the accident report from the NTSB website.

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