Facing a shortage of unmanned aerial vehicles, the US Air Force has ordered two jet-powered Predator-B drones from General Atomics. The Air Force had two versions of Predator-B to pick from. It was expected to pick the turbo-prop version (with its 24-hour endurance and 45,000-foot altitude) but instead picked the jet-powered version with a 12-hour endurance. But the jet-powered version could carry the same 750-pound payload and operate at 60,000 feet.--Stephen V Cole