EDWARDS AIR FORCE BASE, Calif. -- The sky over the Mojave has for 60 years been home to some of the world's most innovative and advanced flight-test programs. The United States' first jet flew here during World War II. Chuck Yeager became the first pilot to exceed the speed of sound here, way back in 1947. The incomparable X-15, the fastest airplane ever, first flew here. Even the space shuttle made its inaugural flight over this Southern California desert.

Tucked away in a corner of the sprawling air base here is NASA's Dryden Flight Research Center. Some of the coolest things in the world are tested here, and the centerpiece of every flight-test program are the workhorses that serve as flying laboratories.

NASA has over the years relied upon various airplanes to test new tricks and technology. These days the F-18 is the mainstay of the NASA Dryden test fleet. Whenever an engineer comes up with a new idea, it is tested on an F-18. Once installed, these modifications are rarely removed. The bits and pieces read like a history of flight-test research.

Among the most heavily modified F-18s is a plane known as No. 853. It has been the testbed for several projects, including flying with a bending wing and being tweaked to fly like a plane missing a wing.

NASA let us into the hanger to have a look at No. 853 and learn a little more about some of the unusual feats it has accomplished.

Above: No. 853, high above the Mojave in 2004 during one of its more interesting projects, the Active Aeroelastic Wing project. The goal was to explore twisting, or warping, the wing to provide roll control at transonic and hypersonic speeds.

Photo: NASA