Being a metric user, 200ft is all french to me. But in this thread here...
http://www.subsim.com/radioroom/showthread.php?t=129919
.... you will find two posts from Donut. In them he explains how deep you can be bombed (historically) and he posts a tip for modding out air night attacks. If 40m is anywhere near 200ft, then expect a big surprise when you read his post
