Iran hijacked US drone... (Growing up in Iran I've learned Iranians are very intelligent – read the story)

How did Iran manage to capture a US robotic surveillance plane, which looks remarkably undamaged in an Iranian video? The US initially claimed the drone went astray over Afghanistan and blamed a malfunction, but Iran said it had brought the craft down 200 kilometres inside its border earlier this month.

Now the Christian Science Monitor reports that Iran jammed GPS signals and fooled the drone into landing at an Iranian base. "The GPS navigation is the weakest point," an unnamed Iranian engineer analysing the captured drone told a Monitor correspondent inside Iran. "By putting noise [jamming] on the communications, you force the bird into autopilot. This is where the bird loses its brain."

Once the drone lost its bearings, the engineer said, Iranians were able to reprogram its internal mapping system to think that its home base was an Iranian site at almost the same altitude. He added that the slight mismatch in altitude caused a rough landing that damaged the robot plane's landing gear and underside.

GPS signals are broadcast by satellites, so they are weak near the ground. That makes them vulnerable to interference from stronger nearby signals. Even military versions of GPS are vulnerable to electronic warfare, which usually seeks to disable key systems to bring down a plane. The Iranians claim to have taken that one step further by electronically capturing control of the remotely controlled robot craft.  A former Navy specialist told the Monitor that hostilely reprogramming a GPS to fly to a different home is "certainly possible".

Built by defense contractor Lockheed Martin, the RQ-170 Sentinel craft is a high-flying surveillance craft, which uses stealth technology to elude detection. Although details are classified, some information has leaked, including photos which match those shown by Iran.

At the time the US lost control, it was operated by the CIA. With no US controller operating it, the unmanned aircraft should have crashed - yet the one Iran displayed showed only a dent, although its landing gear was hidden.

If that's what happened to the CIA's Sentinel, it's going to prompt some serious rethinking of how to wage robotic warfare. You don't want the enemy to be able to capture and reprogram your robots so they fight you. (story adapted from New Scientist Magazine)