(AP) — Federal accident investigators are headed to a desert crash site where a winged spaceship designed to give wealthy tourists a high-altitude view of Earth broke up during a test flight, killing one pilot and badly injuring another. Branson, said it was "among the most difficult trips I have ever had to make" but that he wants to be "with the dedicated and hardworking people who are now in shock at this devastating loss." Branson has been the front-runner in the fledgling race to give large numbers of paying civilians a suborbital ride that would let them experience weightlessness at the edge of space. The National Transportation Safety Board was sending a "go team" Saturday to the crash area about 20 miles from the Mojave Air and Space Port, where the flight originated. The accident occurred just as it seemed commercial space flights were near, after a period of development that lasted far longer than hundreds of prospective passengers had expected. SpaceShipTwo is based on aerospace design maverick Burt Rutan's award-winning SpaceShipOne prototype, which became the first privately financed manned rocket to reach space in 2004.