Is the number of relief pilots regulated?

Question

This article hints that the number of relief pilots isn't mandated. Wouldn't requiring more relief pilots for longer flights be safer and ethical? I personally prefer airlines that overwork their pilots less!

I'm asking more about North American and European airlines, not just Asia.

As part of the agreement ending the strike, CAL [China Airline] pilots promised not to strike for three and a half years and the airline increased the number of pilots rostered for long haul flights. CAL now rosters three pilots on flights over eight hours, up from two pilots previously, and four pilots on flights over 12 hours, up from three pilots previously.

Answer 1

Pilot (and other air crew) rest time is an important factor in aviation safety. I'm not sure where you picked up that it "isn't mandated", but that is quite false. For example:

• United States: 14 CFR § 91.1059 - Flight time limitations and rest requirements: One or two pilot crews.
• Europe: EASA welcomes new flight time limitations rules (older article, possibly out of date)

Other aviation authorities around the world have their own regulations on how much pilots can work at once. These limits are very strongly respected and enforced.

I am not familiar with the regulations in the Asian countries referenced in the article you linked to, but I would be very surprised if they did not have similar regulations.

Answer 2

In North America under the FAA the regulation is not written such that the FAA requires a certain number of qualified flight crew on a given flight explicitly, its regulated by duty time as per §91.1059, and in order to comply with those regulations there may need to be multiple flight crews aboard a given aircraft. Assigning by quantity is not a good metric in this situation, for example 3 pilots assigned to a flight all of whom are rolling off another flight will be far more fatigued than two pilots who have just completed a mandatory rest period. As such §91.1059 provides us with a rubric that allows us to determine how many qualified pilots we may need to bring along which directly regulates quantity by duty time.