Something like this hasn't happened in a long time. Or at all.
A (training) sailing ship of the Ecuadorian Navy encountered and
seized a drug-smuggling submarine., so young cadets defeated drug runners.
Surely gaming material, but I am not sure what genre. Or setting. Or mood.
It screams science fiction, coming-of-age space cadets and light-hearted comedy, but surely there are more possibilities.
In fantasy, a nautical magic college on a field trip, encountering a magic underwater vessel manned by goblin-pirates, running necromantic artefacts?
Other ideas?