I wasn't the only one pleased to finally reach this last episode...though for different reasons than the Harekaze's torpedo officer.
Actually, the final episode was not terrible and the series as a whole would have been significantly better if episode 11 had not existed. The few good moments of that debacle could have easily been incorporated into this story.
The whole 'Captain has a nervous breakdown' plot point from episode 11 was chucked into the scuppers and the climax revolves around a fairly satisfying battle with Captain Akeno handling her ship with great verve as it is is gradually shot out from under her. Some old friends arrive to provide support at a crucial moment...
...and Akeno uses the opportunity to get her stricken vessel (and the only available stock of the anti-zombie vaccine) alongside Musashi for a desperate boarding action in an attempt to save the day.
Afterwards, the crippled Harekaze is towed into port...
... where she sinks at her moorings as the sun sets.
Note: They are explicitly in Yokusuka, which is surrounded by mountains and cliffs, except to seaward, ie: to the east-southeast. Yes, the sun is setting in the east.
However, we never do get an explanation for why this senior officer (who, I note, is outside without her combo cover) has cat ears.
"Is it over?...Is it finally over?"
All in all, High School Fleet had some neat moments but required way too much suspension of disbelief to be taken seriously, I confess, I liked its tendency towards didactic solutions to the problems the girls faced but the show devolved rapidly into a largely inchoate mess.
The one sane person on the ship...screaming internally.
I think it was Pixy
who hypothesized a process whereby writers put a bunch of current tropes on a dartboard, throw three darts and build a show based upon where those darts landed, in this case 'Cute Girls in HighSchool Doing Club Stuff' 'Naval Otakuism'...'Zombies'. Sometimes it would probably be a good idea to ponder ones options...and go back to the dartboard.