and says that the door is open. and if i release it, it goes back to the normal position. >> and the norm means locked? >> that is correct. >> reporter: according to the airbus operations door there is a keypad that allows the entry if you noeknow the code, but if the person inside switches it to lock the keypad won't work for five minute and there is another that goes beyond five minutes. >> and ki the key pad and hold it in the lock position, and he cannot use the keypad or anything, because it can't go in. >> reporter: and so to keep the co-pilot out, what do you have to do? >> if he knew the keypad number i hold lock and he can't get in. >> and can you manually fly this and hold the lock button? >> oh yes, easy. >> reporter: but then that s ais a purposeful act? >> very much so. >> reporter: again and again, we fly through the scenarios in