407 meters?????? That exceeds what I thought was possible by about a hundred meters
Hope you don't think I'm hijacking, but its relating to a similar experience I had last night west of the Canaries. I was in my VIIC and I'd already sunk 4 merchants. A Black Swan Class escort lit me up with his searchlight. (I was using the mantra of 'Be More Aggressive' after all.)
After a crash dive I thought I'd take it to 160m and follow the convoy along throwing caution to the wind, ahead standard, silent running off, whilst I reloaded my torps.
After a few 'wasserbomb' warnings and a lot of rocking about without damage, I thought I'd crank it up to flank speed and follow my course straight to cut underneath the convoy, and sit and wait for them to come to me whilst I reloaded. (Yes, too reckless I know, but I was 'being more aggressive'.)
Another 'wasserbomb' warning, then a long pause, then BANG, sub almost tipped 90 degrees over:
Deck gun destroyed, radio destroyed, hydrophone destroyed, fore batteries destroyed. Major flooding.
I started to sink and slammed it into back emergency, managing only 2kts, but still sinking slowly. I stopped at about 230m and managed to get the flooding under control. Once I'd stabilised the sub I ordered all stop, as I wasn't going to get any power from my electrics anymore, and went to silent running, hanging in the water whilst the Black Swan gave me hell.
Miraculously he never found his target again and after another four or five depth charge runs, and some bouncing around, I was left alone. I had to break silent running again to stop some flooding which reappeared in the bow torpedo room, but man I was lucky.
After my brush with oblivion, my only objectives now were getting some fresh air into the pressure hull, then getting to dry land.
With no hydrophone and no idea what was going on above my head, I gave it 24 hours sitting motionless right where I was, then bit the bullet and blew ballast.
Popped the hatch, nothing in sight, I breathed a sigh of relief and headed back to base, crippled but happy to be alive, and kind of smug that I'd put 20,000 tons at the bottom in any case.