Mission safety evaluation report for STS-48, postflight edition

Space Shuttle Discovery was launched into a 57 deg inclination orbit from the Kennedy Space Center (KSC) Launch Complex 39A at 7:11 p.m. EDT on 12 Sep. 1991. STS-48 was the second mission since return-to-flight to have KSC as the planned end-of-mission landing site, and the first mission to have a planned night landing at KSC. However, due to weather conditions at KSC, Discovery flew one extra orbit and landed at Edwards AFB, Calif. at 3:38 a.m. EDT on 18 Sep. 1991. Operation of all systems was generally satisfactory during the 5 day mission. On flight day 3, the Upper Atmospheric Research Satellite (UARS) was deployed from Discovery's payload bay 350 statute miles above Earth. This orbiting observatory will study mankind's effects on the planet's atmosphere and its shielding ozone layer. STS-48 safety risk factors are addressed that represent a change from previous flights, factors from previous flights that had an impact on this flight, and factors that are unique to this flight.