Lot of two signed covers includes: an FDC with a color cachet honoring the X-1, 50th Anniversary of the 1st Supersonic Flight, signed by the entire crew: Chuck Yeager (pencil), Fred Ascani, Bob Hoover and Robert Cardenas; and a 9.5 x 4 commemorative cover with a color cachet honoring X-15 Pilots, 1959-1999, signed in pencil by Robert White, Scott Crossfield, William Pete Knight, Bill Dana and Joe Engle. This is a limited edition cover, #1113/1500, flown over Edwards AFB by X-15 pilot Joe Engle. In fine condition. R&R COA.