In the 1970s Soviet air defense systems improved and the U.S. realized they had to develop aircraft to counter this. Lockheed Skunk Works was tasked with the job and two aircraft were built under the code name Have Blue that proved stealth aircraft could be produced. As a result the F-117 Nighthawk was developed and first flew in 1981 with the first production F-117 80-10785 making its maiden flight on April 20, 1982 but it wasnt until 1988 that the Pentagon confirmed its existence.