Columbia was also originally fitted with Lockheed-built ejection seats identical to those found on the SR-71 Blackbird.
These were active for the four orbital test flights, but deactivated after STS-4, and removed entirely after STS-9.
 Columbia was also the only spaceworthy orbiter not delivered with head-up displays for the Commander and Pilot, although these were incorporated after STS-9.
Like its sister ships, Columbia was eventually retrofitted with the new MEDS "glass cockpit" display and lightweight seats.
Columbia was also originally fitted with Lockheed-built ejection seats identical to those found on the SR-71 Blackbird. These were active for the four orbital test flights, but deactivated after STS-4, and removed entirely after STS-9.  Columbia was also the only spaceworthy orbiter not delivered with head-up displays for the Commander and Pilot, although these were incorporated after STS-9. Like its sister ships, Columbia was eventually retrofitted with the new MEDS "glass cockpit" display and lightweight seats.
Space Shuttle Columbia