Northrop X-21
| X-21 | |
|---|---|
| Northrop X-21A | |
| General information | |
| Type | Experimental aircraft |
| Manufacturer | Northrop |
| Primary user | National Aeronautics and Space Administration (NASA) |
| Number built | 2 |
| History | |
| Introduction date | Experimental |
| First flight | 18 April 1963 |
| Retired | 1968 |
| Developed from | Douglas B-66 Destroyer |
The Northrop X-21A was an experimental aircraft designed to test wings with laminar flow control. It was based on the Douglas WB-66D airframe, with the wing-mounted engines moved to the rear fuselage and making space for air compressors. The aircraft first flew on 18 April 1963 with NASA test pilot Jack Wells at the controls. Although useful testing was accomplished, the extensive maintenance requirements of the intricate laminar-flow system caused the end of the program.