Understand your flight

What if the pilot gets sick during the flight?

Airliners always carry at least two qualified pilots, and the rules about who stays at the controls are strict. Here's how it works.

4 official sources, listed at the end Checked October 18, 2026
Photo: Mertbiol, CC0
In this article · 6 sections
  1. The short answer
  2. At least two pilots, every time
  3. Strict rules about leaving the seat
  4. Medical checks, more often with age
  5. If a pilot does become ill
  6. Keep reading

The short answer

There's always a second qualified pilot at the controls. Airliners are built and staffed so that no flight depends on one person.

At least two pilots, every time

US rules require every airline flight crew to include at least two pilots: a pilot in command (the captain) and a second in command (the first officer).1 The first officer isn't a trainee watching. On US airlines the second in command must hold an airline transport pilot certificate, the same top-level licence the captain holds, plus a type rating for the airplane being flown.4

Some longer flights carry extra pilots, so crew members can take planned rest while a qualified relief pilot takes their seat.2

Strict rules about leaving the seat

Required pilots must stay at their stations with their seat belts fastened throughout the flight. The only exceptions are brief absences for duties connected with the flight, for physiological needs (yes, the bathroom), or for a planned rest period when a qualified relief pilot takes their place.2

Medical checks, more often with age

A captain on a US airline must hold a first-class medical certificate, the highest class. It has to be renewed every 12 months, and every 6 months from age 40. From age 60, every pilot on the crew must hold one.3

If a pilot does become ill

This is exactly why the rules insist on two pilots who stay at their stations.1, 2 If one becomes unwell, the other qualified pilot is already in the seat beside them and keeps flying. The crew can then decide whether to continue or land at a nearby airport.

Where you might notice something: a flight attendant asking "Is there a doctor on board?" or an announcement about a diversion. Both are signs the system is working as intended.

Keep reading

Quick answers

How many pilots are on a commercial flight?

US airline rules require at least two pilots, a pilot in command and a second in command. Some longer flights carry extra pilots so crew members can take planned rest.

Can the co-pilot land the plane?

Yes. The first officer is a fully qualified airline pilot, not a trainee. US airline rules require the second in command to hold an airline transport pilot certificate and a type rating for the airplane, the same top-level licence as the captain.

Do airline pilots have medical checks?

Yes. A captain on a US airline needs a first-class medical certificate, which must be renewed every 12 months, or every 6 months from age 40.

Can both pilots leave the cockpit?

No. Required pilots must stay at their stations with seat belts fastened, except briefly for duties, physiological needs or a planned rest when a qualified relief pilot takes over.

Sources

(4)
  1. 14 CFR § 121.385, Composition of flight crew
  2. 14 CFR § 121.543, Flight crewmembers at controls
  3. 14 CFR § 61.23, Medical certificates: requirement and duration
  4. 14 CFR § 121.436, Pilot qualification: certificates and experience requirements

Facts last checked against these sources: October 18, 2026.