Hi, lederhosen! BuckeyeBob from the simhq forum (I have many names)!
This is the well-known crash-dive bug. I thought that LSH had cured this bug, but if not, I think it can be cured by enabling H.sie's patch and Steibler's add-on. If I am incorrect, someone more knowledgeable than I will be along shortly to straighten both of us out.
Happy hunting!