IMSAFE: how a pilot decides they are fit to fly today

Every student learns to preflight the airplane. Fuel, oil, control surfaces, tires, the works. Almost nobody arrives knowing that there is a preflight for the pilot too, and that it is the one with the worse consequences when you skip it.

The mnemonic is IMSAFE, and it is six questions you ask yourself before you drive to the field, not after you are already strapped in and feeling committed.

I — Illness

Not “am I dying,” but “is anything about me not working normally today.” A head cold is the classic one. Blocked sinuses that feel like nothing on the ground will hurt on the descent, because the air trapped in your head has to equalize and it cannot. A stomach bug that has you thinking about your stomach is a stomach bug that is not thinking about the airplane.

M — Medication

Two questions here, and people usually only ask the first. First: is this medication itself disqualifying or impairing? Second, and the one that catches people: why am I taking it? A pilot who is fine on an antihistamine may still not be fine with whatever made the antihistamine necessary. If you are on something new, ask me or ask an Aviation Medical Examiner before you fly on it. Over-the-counter is not the same as harmless — plenty of the sleepy-making allergy medicine on a supermarket shelf is a no-fly for hours after the last dose.

S — Stress

The kind of stress that matters in a cockpit is the kind that is still running in the background while you fly. Money, a deadline, an argument in the car park. It does not make you stupid; it makes you narrow. You stop scanning, you stop hearing the radio properly, and you fixate on whatever you are already doing.

I would rather cancel a lesson than have a student pay $175 an hour to be somewhere else in their head.

A — Alcohol

The regulation is eight hours from bottle to throttle and below 0.04 blood alcohol, and you may not fly while under the influence at all. The regulation is the floor, not the target. Alcohol takes longer to leave your judgment than it takes to leave your breath, and at altitude the leftovers are worse than they are on the ground. Twenty-four hours is the number I actually use.

F — Fatigue

The one that gets good pilots. Fatigue does not feel like anything from the inside — that is the whole problem with it. It feels like normal, and then you read back a clearance you did not actually hear and you have no idea why.

If you slept badly, if you have been up since four, if you flew a red-eye yesterday: that is a ground day. In Southwest Florida we get 300-plus flyable days a year, so there is always another one. There is no lesson worth flying tired for.

E — Emotion

Emotion, or eating, depending on who taught you. Both are real. Take the emotional one seriously: anger and grief both do the same thing stress does, only harder. And eat something. A student who skipped breakfast is a student who gets quietly worse forty minutes into a lesson and cannot tell you why.

The part nobody tells you

IMSAFE only works if a “no” is allowed to be a “no.”

That means you have to have decided, in advance and on the ground, that cancelling is a normal outcome and not a failure. If cancelling feels expensive — because you drove an hour, because the weather is finally good, because you already told someone you were flying today — then you will find a reason to call yourself safe when you are not. That pressure has a name in the textbooks, external pressure, and it is the most common ingredient in the accident reports I read.

Here is how I handle it with my students: if you call me and say “I’m not right today,” we move the lesson and nothing else is said about it. No explanation needed, no charge, no raised eyebrow. That is not me being nice. It is me making sure the six letters can do their job.

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Learning to fly at Page Field? A Discovery Flight is a real first lesson — briefing, flying, debrief — and this is the kind of thing we cover in the briefing.