For two years, Google has quietly been developing autonomous flying vehicles that can be used to deliver packages for disaster relief or for commerce purposes, the company revealed Thursday. The program, dubbed Project Wing, has been housed under Google X, the company’s secretive facility where it created other projects like Google Glass and its self-driving cars. “Self-flying vehicles could open up entirely new approaches to moving goods—including options that are cheaper, faster, less wasteful and more environmentally sensitive than what’s possible today,” the company says in a document describing the effort.