沈船 ちんせん捜索 そうさく救助 きゅうじょ計画 けいかくだったら
chinsensōsakukyūjokeikakudattara

Noun
Da Copula

The "-tara" conditional form ("if/when…") of 沈船捜索救助計画

1. If it were a plan to search for and rescue the sunken ship.; If it had been a plan to search for and rescue the sunken ship.

Tara Conditional