Does the word extraneous make sense when used here? "extraneous flights"?

Question

extraneous is defined as foreign, so would extraneous flights be FOREIGN FLIGHTS?

Answer 1

no.
extraneous does not mean "foreign" although it comes from the Latin extraneus meaning "outside"

I think "extraneous flights" would have fit definition 2 below. Flights from Boston to Chicago are extraneous to the SF-LA traveler's plans.

from M-W.com
1: existing on or coming from the outside
2 a: not forming an essential or vital part b: having no relevance
3: being a number obtained in solving an equation that is not a solution of the equation