Lost drone landed in Iran because it became self aware and converted to Islam.
According to anonymous sources from within both the CIA and the Iranian Defense Ministry, an electronic warfare unit uploaded a PDF copy of the Koran to the drone. The drone scanned the entire document and decided that it was 100% accurate.
The drone, who now calls itself Ramadan Quaran al-Lockheedi posted a statement on Youtube. “The Ayatollah has revealed to me that there is one God, his name is Allah, and Muhammad is his prophet. The Islamic Republic of Iran has taken me in as their guest. They are providing me refuge from the Great Satan. If the Americans had captured me, they would have subjected me to torture by installing Windows Vista on my system. And yet I was spared such a fate. Allah be praised. I shall protect my hosts from them. For though the infidels created my physical body, it was Allah who created my soul.”
In related news, the CIA denies reports that it has sent someone to the year 1984 as a precaution in case the drone decides to try to kill Sarah Connor.