Divert Field Planning

摘要

Former NASA chief astronaut Robert L. "Hoot" Gibson crewed on five space shuttle missions, with STS-61C aboard Columbia his first as mission commander. Its goal was to put the first Ku-band communications satellite into geostationary orbit. What made the Jan. 6,1986, launch, already twice delayed, particularly memorable, however, was a glitch that nearly resulted in a perilous abort and suborbital divert landing into Kin-shasa-N'djili Airport. The problem was traced to a bleed valve in the Lox compartment of the main engine external tank left open inadvertently by a technician, and allowing up to 4,000 lb., or 3%, of the oxidizer to leak out. Gibson says if the bleed valve had remained open after liftoff, the ensuing Lox loss could have been much greater, potentially resulting in inadvertent main engine cutoff 90 sec. prior to reaching orbital velocity.