Not much. That's why you send someone to actually take a look up close, and see if that's actually the case or not. OTOH, both pilots dozing off or becoming dis

Not much. That's why you send someone to actually take a look up close, and see if that's actually the case or not. OTOH, both pilots dozing off or becoming distracted - now that tends to happen, too. In that case, "knock knock, who's there? German Airforce" tends to resolve the situation fairly quickly and without further incident*, as seen here. (Other than "a wild mountain of paperwork appears")