A-12s
Tail number/ build number

YF-12A

SR-71s

AF Serial Numbers assigned for the SR-71: 61-17950 through 61-17985

Sources:
  • "Lockheed Skunk Works, The First 50 Years" by Jay Miller
  • "Lockheed SR-71 Blackbird" by Paul Crickmore
  • "Lockheed SR-71, The Secret Missions Exposed" by Paul Crickmore