Where does this definition of route-proving flight come from?
This entry for route-proving flight is sourced from Main Dictionary, one of the dictionaries and corpora merged into Lughet.
Is route-proving flight a noun, verb, or something else?
In this entry, route-proving flight is tagged as 2n..
What is Lughet?
Lughet is a free trilingual dictionary covering nearly five million entries across Uyghur, Chinese, and English, drawn from more than ten source dictionaries and corpora.