According to this Yahoo! News article: http://news.yahoo.com/super-secret-hypersonic-aircraft-flew-skin-152315621--abc-news-topstories.html http://news.yahoo.co

According to this Yahoo! News article: http://news.yahoo.com/super-secret-hypersonic-aircraft-flew-skin-152315621--abc-news-topstories.html http://news.yahoo.com/super-secret-hypersonic-aircraft-flew-... "While the test was very public, the details of the HTV-2's design, stability system and potential purpose remain highly classified."