[ChrisC-POV]

Similarly, if a FAA-licensed pilot requires glasses to fly, it becomes a legal requirement that they carry a readily-accessible second pair while exercising the privileges of their license. This even applies if they use contacts (and, no, extra contacts don’t count :).

It is also a requirement for international flight operations under ICAO regulations. I’m pretty sure this regulation (or something close to it) is enforced by just about every flight-licensing authority worldwide.

It’s plain good sense and I’m glad it’s in there. A plane cannot pull over to the side of the highway while the pilot fumbles around trying to dig his glasses out from under the seat :)

(As a side note, this rule isn’t just for dropped spectacles: there have been cases where they literally get sucked out of the airplane if a cockpit window fails or where a bird strike causing facial injuries also damages the pilots glasses).