STS-51-D was the 16th flight of NASA's Space Shuttle program, and the fourth flight of Space Shuttle Discovery. The launch of STS-51-D from Kennedy Space Center (KSC), Florida, on April 12, 1985, was delayed by 55 minutes, after a boat strayed into the restricted Solid Rocket Booster (SRB) recovery zone. STS-51-D was the third shuttle mission to be extended.
The crew attempt to activate Syncom IV-3 via a "flyswatter" device attached to Discovery's Canadarm
Back row: S. David Griggs, Charles D. Walker, Jake Garn Front row: Karol J. Bobko, Donald E. Williams, Rhea Seddon, Jeffrey A. HoffmanSpace Shuttle program← STS-51-C (15)STS-51-B (17) →
Telesat-I during deployment
Syncom IV-3 during deployment
Space Shuttle Discovery is a retired American spacecraft. The spaceplane was one of the orbiters from NASA's Space Shuttle program and the third of five fully operational orbiters to be built. Its first mission, STS-41-D, flew from August 30 to September 5, 1984. Over 27 years of service it launched and landed 39 times, aggregating more spaceflights than any other spacecraft to date. The Space Shuttle launch vehicle had three main components: the Space Shuttle orbiter, a single-use central fuel tank, and two reusable solid rocket boosters. Nearly 25,000 heat-resistant tiles cover the orbiter to protect it from high temperatures on re-entry.
Discovery in orbit in 2011, during STS-133, the orbiter's final flight
Space Shuttle Discovery at the Steven F. Udvar-Hazy Center
Discovery rollout ceremony in October 1983
On the maiden voyage of Discovery: Judith Resnik, Henry Hartsfield, Michael L. Coats, Steven A. Hawley, Charles D. Walker, and Richard M. Mullane