As depressin as it is, I liked the last scene. No, not because of the explosions.
Because U96 was in itself a character in that film. You're saying to yourself "uhh, Radtgaeb, it was a boat!". Yeah, but one will find that authors and directors like to take inanimate things and turn them into characters (The truck in "Grapes of Wrath"...the cities of New York and Chicago in "Sister Carrie") this is a form of that which we like to call 'personification'.
Anyway, U96 was a character (a dynamic character at that--situation FUBAR to surviving, bluntly) and the men grew attached to it, cared for it, loved it even. They spent days to fix it while on the bottom and God knows how many weeks limping home, probably. The well being of the ship meant their own well being. Then, after they have made their way home and are getting the heroes welcome, the planes swoop out of nowhere and destroy that which they fought so hard to preserve. The most moving scene I've ever seen in any movie (save "Schindler's List) is at the end where the captain is staring at the ship as she sinks; and as she settles on the bottom, he dies as well.
So that's may favorite scene!