Rescuing a diving boat

[BenG]

Is there anyway to resuce a boot that seems to be falling towards the ocean floor.

After and attack on a convoy I was trying to make my way out of they and while I was still fairly shallow I was hit by a big DC attack and sent to the dark depths on my way down I tried everythign I could to control the fall I.e. blow ballast and click on a new depth, but by the time control was regaigned the Hull intergerity had fallen so much that the Ub-bot was destryoed (at about 100m) having just been much deeper.

In real life a chief of the boat had a few more tools and his disposal e.g. pumping ballast water around to change the trim, control dive planes indidually etc.. is there anythign else I cna do other than tell the CE to make his depth x or to blow ballast?