It helps if you give your source. In this case, Google finds me http://www.dtic.mil/dtic/tr/fulltext/u2/a183431.pdf "Spatial Orientation in Flight," a technical paper on aerospace medicine. "Unorientation" is a very unusual word. It's not in the m-w.com online dictionary. It seems to be a technical term used in the study of human favors in aviation. In fact it may even be a word coined by the writers. Fortunately, they themselves give the definition: "For those reasons, we find it necessary to restrict the use of the term 'spatial disorientation' to the condition wherein one rot only has an orientational illusion but also needs to have correct perception of orientation for controlling his position, attitude, or motion. When one has an orientational illusion but has no need for correct information about his orientation, we say he has spatial unorientation." "Unorientation" may be a well-understood term in the narrow technical field of aerospace medicine, or it may be a word that the authors coined for their own convenience, used in this paper but not adopted elsewhere.

I really hope this isn't in an English textbook. It's terrible writing. "Unorientation" isn't really an accepted word. We only understand it because we understand the mechanics of English. You can understand "dis-" to mean "removed, taken away" and "un-" to mean "without". Just be aware that these prefixes come from completely different origins. Basically, the text means that the pilot should switch to autopilot (if possible) and just chill out for a few secs.

I have contacted an acquaintance of mine who happens to be a very experienced aerospace professional, and he replied to me: Hi Dan, This is the first time I have ever heard the word “unorientation”. I’m going to forward this to two colleagues whose specialty is neurovestibular orientation and see what they say. I’ll get back to you.

that is mortal that will be distory one day......

that is mortal that will be distory one day......