The aeromedical section of the FAA written isn't trivia — it's about recognizing how the human body fails at altitude and under stress, so you can catch it early. Here are the big ones.

Hypoxia

Too little oxygen reaching the body, usually from altitude. Early signs are sneaky: euphoria, poor judgment, tingling, and blue fingernails/lips. The fix is oxygen and descent. Regulations require supplemental oxygen for the crew above certain cabin altitudes for good reason.

Hyperventilation

Breathing too fast (often from anxiety) blows off too much carbon dioxide, causing dizziness and tingling — symptoms that overlap with hypoxia. The remedy is to slow your breathing consciously.

Spatial disorientation and illusions

Without a visible horizon, your inner ear lies to you. Trust the instruments, not your senses. Classic visual illusions — a wide runway making you feel low, a black-hole approach at night — lead to dangerous corrections if you don't know them.

The IMSAFE checklist

Before every flight, self-assess: Illness, Medication, Stress, Alcohol, Fatigue, Emotion/Eating. It's a simple personal-minimums tool the written expects you to know.

A worked example

On a night cross-country you feel lightheaded and your fingertips tingle at 11,500 ft. Hypoxia is the prime suspect — descend and use oxygen rather than pressing on.

Frequently asked questions

How is hypoxia different from hyperventilation?

Symptoms overlap, but the causes differ. If in doubt at altitude, treat for both: use oxygen, descend, and slow your breathing.

Lock in the safety material with explanations that teach the why: study free.