Pilot who survived identified as Peter Siebold , 44 , Sheriff 's Office says . Authorities identified pilot who died as Michael Tyner Alsbury , 39 . Virgin Group founder Richard Branson vows to find out ' what went wrong ' Both pilots worked for Virgin Group 's partner , Scaled Composites .
Pilot who survived identified as Peter Siebold , 43 , Sheriff 's Office says . Authorities identify pilot who died as Michael Tyner Alsbury , 39 . Virgin Group founder Richard Branson vows to find out 'what went wrong ' Both pilots worked for Virgin Galactic 's partner , Scaled Composites .