NASA - STS-51CNASA - National Aeronautics and Space Administration› Follow this 
link to Login to MyNASALog In To MyNASA|› Sign Up› More Preferences
HomeNewsNews & FeaturesRecovery InformationShuttle & StationMoon & MarsSolar 
  SystemUniverseAeronauticsEarthTechnologyNASA in Your LifeNASA PeopleNASA 
  HistoryMissionsMissionsMission CalendarLaunch 
  ScheduleMultimediaMultimediaImagesVideoPodcastsNASA TVInteractive Features3D 
  ResourcesRSS FeedsBlogsWorldbook@NASAAbout NASAAbout NASAWhat NASA 
  DoesRecovery InformationNASA LeadershipCareers@NASANASA LocationsNASA 
  CalendarBudget and PerformanceReportsResearch OpportunitiesRequest a NASA 
  SpeakerRequest a NASA 
  ExhibitConnectBlogsRSSTwitterFacebookYouTubeFlickriTunesMore Social Media 
  ...NASA Home    |    Missions    |    Space Shuttle    |    Shuttle Missions   
   |    ArchivesSendBookmarkPrintMissionsMissions HighlightsCurrent 
  MissionsCurrent MissionsSpace ShuttleShuttle MissionsArchivesBehind the 
      ScenesLaunch & LandingMultimediaNews & Media ResourcesVehicle StructurePast 
MissionsFuture MissionsLaunch ScheduleMission CalendarSpace ShuttleMission 
ArchivesText SizeSTS-51C Mission: Department of Defense
Space Shuttle: Discovery
Launch Pad: 39A 
Launch Weight: 250,891 pounds
Launched: January 24, 1985 at 2:50:00 p.m. EST
Landing Site: Kennedy Space Center, Florida
Landing: January 27, 1985 at 4:23:23 p.m. EST
Landing Weight: Classified
Runway: 15 
Rollout Distance: 7,352 feet
Rollout Time: 50 seconds
Revolution: 49
Mission Duration: 3 days, 1 hour, 33 minutes, 23 seconds
Orbit Altitude: 220 nautical miles
Orbit Inclination: 28.5 degrees
Miles Traveled: 1.3 million 

Crew Members

                    

Image above: STS-51C Crew photo with Commander Thomas K. Mattingly, II, Pilot 
Loren J. Shriver, Mission Specialists Ellison S. Onizuka, James F. Buchli and 
Payload Specialist Gary E. Payton. Image Credit: NASA 

Launch Highlights

 The launch scheduled for January 23 was scrubbed due to freezing weather 
conditions. (Orbiter Challenger was scheduled for Mission 51-C but thermal tile 
problems forced the substitution of Discovery.)

The countdown phase was completed satisfactorily, however, two minor orbiter 
problems were noted during that period. The first occurred during the T-3 hour 
hold and involved a force fight in the right inboard elevon actuator between 
channel 4 and channels 1, 2, and 3. The condition corrected itself within 22 
seconds after the Auxiliary Power Unit (APU) start up at T-5 minutes. A similar 
problem with the same channels in the same actuator occurred on STS 41-D (the 
first flight of this vehicle).

The second problem that was noted during the countdown phase was the high helium 
concentration in the orbiter mid-body. A pressure decay test showed no 
significant system leakage. The high helium concentration disappeared when the 
main propulsion system (MPS) gaseous helium system was pressurized to the flight 
level.

System operations were all nominal during the ascent phase. Solid rocket booster 
(SRB) motor performance was near the predicted levels and well within the 
allowed envelopes. The external tank and MPS performance was excellent with main 
engine cutoff (MECO) near the predicted time.

At external tank separation, the backup flight system (BFS) did not 
automatically proceed to major mode 104. The crew performed the necessary manual 
procedures, and the BFS operated satisfactorily until the deorbit maneuver when 
the BFS time for deorbit maneuver ignition was 8 seconds late. However, the BFS 
operated satisfactorily for entry.

Mission Highlights

This was the first mission dedicated to the Department of Defense. The U.S. Air 
Force Inertial Upper Stage (IUS) booster was deployed and met the mission 
objectives.

  NASA's John F. Kennedy Space CenterRelated Sites>  NASA's Orbiter Fleet
  > NASA's Launch Schedule
  > Shuttle Reference Manual
  > Shuttle Archives  › Back To Top NASA HomePage Last Updated:November 23, 2007 
Page Editor:Jeanne Ryba 
NASA Official:Brian DunbarBudgets, Strategic Plans and Accountability 
  ReportsEqual Employment Opportunity Data Posted Pursuant to the No Fear 
  ActInformation-Dissemination Policies and InventoriesFreedom of Information 
  ActPrivacy Policy & Important NoticesNASA Advisory CouncilInspector General 
  HotlineOffice of the Inspector GeneralNASA Communications PolicyContact 
  NASASite MapUSA.govExpectMore.govOpen Government at NASAHelp and Preferences