Its a mod,and can be found at the link below.
"Real Damage Mod For 1.3 and New DC/Sonar Fix (10.6kb) by gouldjg & Jungmans. It adds exploding crew members to different areas of ships and planes, was not hard to do and it’s mainly for the eye candy guys like myself. (Watch carefully and you will see crew being thrown from the planes in a random fashion or thrown from ships life boats and command decks). It has strengthened the upper parts of many of the ships, as someone said; it looked silly when a BB command deck gets blown of bye the U-boat deck gun. Oil leaks appear on sub when taking damage. No more exploding conning tower because it was impossible to immediately destroy the U-boat once the conning was blown off. The DD keel as been strengthened to reduce chance of flooding after collision with sub conning tower. Increased the flooding probabilities as the new DC does damage at 15 metres and not 50, this looks more realistic when externally viewing. Made it so you do not immediately die, however it does take some good co-ordination and crew management to recover now. More chance of sinking out of control while trying to recover from flooding, I had a great time sinking and managing to gain control at 200 mtrs, hair raising stuff. Remember this is depending on various factors and not necessary all the time as it is impossible to balance the game to do this all the time. To compensate for the realistic fans, I have added a couple of explosives on the sub in varying places where a direct DC hit could and I stress could cause extra damage. The good thing is that as long as you have made a copy of your original Zones. CFG and followed the backup instructions when installing Jungmans mod, you can easily roll back."
Download:
http://www.subsim.com/subsim_files/p...ood_part_2.rar
Wolfy