ちょう音速 おんそく輸送 ゆそう でしょう
chōon soku yusōkideshō

Noun
Desu Copula

Expresses probability in a polite manner ("probably…") of 超音速輸送機

1. Supersonic transport, likely.; Probably a supersonic transport.

Polite
Presumptive
Conjecture