STS-51D was the sixteenth flight of a space shuttle and the fourth flight of Discovery. It conducted the fifth landing at Kennedy Space Center, Florida. The launch of Discovery on STS-51D was delayed by 55 minutes when a boat strayed into the restricted SRB recovery zone. STS-51D was the third mission to be extended in the shuttle program. Discovery suffered extensive brake damage and a blown tire during landing. This forced all landings to be done at Edwards Air Force Base in California until the development and implementation of nose wheel steering.
Launch date: April 12, 1985 13:59:05 UTC
Landing: April 19, 1985 13:54:28 UTC