| 
 |  | The
            D-558-I Skystreak was designed as a high-speed research
            aircraft for the U.S. Navy and NACA.  A straight-wing aircraft,
            the first of three Skystreak aircraft flew in 1947. To continue research at higher speeds and
            altitudes, the D-558-II Skyrocket was given swept-wings and a
            rocket motor in addition to its turbojet.  The first of three
            Skyrocket aircraft flew in 1948.  In 1953, a Skyrocket became
            the first aircraft in the world to be flown at Mach 2.  The
            Skyrocket program lasted until 1956. | 
        
          |  |  |  | 
        
          | Specifications
            (D-558-II) |  | Designations | 
        
          |   |  |   | 
        
          |  |  | 
              |  | D-558-I: Initial design with J35-A-11
                turbojet |  |  | D-558-II: Redesign with swept-wings and
                added rocket engine |  | 
        
          |  |  |  | 
        
          | Related
            Pages |  | Related Websites | 
        
          |  |  |  | 
        
          |  |  |  | 
        
          |  |  |  | 
        
          | Stuff
            You Can Buy | 
        
          |  | 
        
          | 
              
                | 
  | Book: Skystreak, Skyrocket and Stiletto: Douglas High Speed
                  X-Planes
 Scotty Libis
 |  |  |  |