Lockheed D-21 Aircraft, Project Tagboard

• Museum of Aviation, Robins Air Force Base, Georgia (GTD-21B #538)
• Museum of Flight, Seattle, Washington (D-21 No. 510 mounted on remaining M-21 #60-6940)
• National Museum of the United States Air Force, Wright-Patterson Air Force Base, Ohio (D-21B #524)
• Pacific Coast Air Museum, Sonoma County, California (D-21B #522)