He served as the pilot of the Space Shuttle Challenger when it was destroyed during the STS-51-L mission, breaking up 73 seconds into the flight, and at an altitude of 48,000 feet (14.6 km),[1] killing all seven crew members.

Following the Challenger disaster, he was promoted posthumously by Congress to the rank of captain, and has had a chair named in his honor at the Naval Postgraduate School (NPS) in Monterey, California.

During the two-year period that followed, Smith flew A-6 Intruders and completed a tour in 1972 during the Vietnam War while assigned to Attack Squadron 52 (VA-52) aboard the aircraft carrier USS Kitty Hawk.

Following NTPS, he was assigned to the Strike Aircraft Test Directorate at NAS Patuxent River, Maryland, to work on the A-6E TRAM and Cruise missile guidance systems.

From Patuxent River, he was assigned to Attack Squadron 75 (VA-75), serving as a maintenance and operations officer while completing two Mediterranean cruises aboard the aircraft carrier USS Saratoga.

Fellow Astronaut Richard Mullane wrote, "These switches were protected with lever locks that required them to be pulled outward against a spring force before they could be moved to a new position."

Later tests established that neither the force of the explosion, nor the impact with the ocean could have moved them indicating that he made the switch changes, presumably in an attempt to restore electrical power to the cockpit after the crew cabin detached from the rest of the orbiter.