(AP) -- The Air Force has delayed launching an experimental space plane because of bad weather.
Friday's launch attempt was canceled because of the threat of lightning near Cape Canaveral in Florida, which also experienced heavy winds and rain. It was rescheduled for mid-Saturday afternoon. Air Force forecasters said there was a 40 percent chance of launch.
The X-37B orbital test vehicle resembles a small shuttle and will be launched aboard an Atlas 5 rocket. The first one was launched last April and landed in December at Vandenberg Air Force Base in California after a 270-day mission. The Air Force says the second mission of the unmanned, winged space plane is for further testing.
The ultimate purpose of the X-37B and details about the craft have long been a mystery.
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