STS-94 (85)

Columbia (23)
Pad 39-A (62)
85th Shuttle Mission
23nd Flight OV-102
KSC Landing (38)


James D. Halsell (4), Mission Commander
Susan L. Still (2), Pilot
Janice E. Voss (4), Payload Commander
Donald A. Thomas (4), Mission Specialist
Michael L. Gernhardt (3), Mission Specialist
Roger Crouch (2), Payload Specialist
Greg Linteris (2), Payload Specialist


Flow A -
OPF-1 -- 12/07/96
VAB -- 03/05/97
TCDT -- 03/13/97
Launch -- 04/04/97

Flow B -
OPF-1 -- 04/09/97
VAB -- 06/04/97
PAD -- 06/11/97 (Estimated)



Mission Objectives:

This is a reflight of the STS-83 Microgravity Science Laboratory (MSL) mission. MSL was originally launched on April 4, 1997 at 2:20pm EST and was intended to be on orbit for 15 days, 16 hours. The mission was cut short due to a problem with Fuel Cell #2 and Columbia landed on 4/8/97 after 3 days 23 hours.

MSL is a collection of microgravity experiments housed inside a European Spacelab Long Module (LM). It builds on the cooperative and scientific foundation of the International Microgravity Laboratory missions (IML-1) on STS-42 and IML-2 on STS-65), the United States Microgravity Laboratory missions (USML-1 on STS-50 and USML-2 on STS-73), the Japanese Spacelab mission (Spacelab-J on STS-47), the Spacelab Life and Microgravity Science Mission (LMS on STS-78) and the German Spacelab missions (D-1 on STS 61-A and D-2 on STS-55).

MSL features 19 materials science investigations in 4 major facilities. These facilities are the Large Isothermal Furnace, the EXpedite the PRocessing of Experiments to the Space Station (EXPRESS) Rack, the Electromagnetic Containerless Processing Facility (TEMPUS) and the Coarsening in Solid-Liquid Mixtures (CSLM) facility, the Droplet Combustion Experiment (DCE) and the Combustion Module-1 Facility. Additional technology experiments will also be performed in the Middeck Glovebox (MGBX) developed by the Marshall Space Flight Center (MSFC) and the High-Packed Digital Television (HI-PAC DTV) system will be used to provide multi-channel real-time analog science video.

The Large Isothermal Furnace was developed by the Japanese Space Agency (NASDA) for the STS-47 Spacelab-J mission and was also flown on STS-65 IML-2 mission. It will house the Measurement of Diffusion Coefficient by Shear Cell Method Experiment, the Diffusion of Liquid Metals and Alloys Experiment, the Diffusion in Liquid Led-Tin-Telluride Experiment, the Impurity Diffusion in Ionic Melts Experiment, the Liquid Phase Sintering II Experiment (LIF), and the Diffusion Processes in Molten Semiconductors Experiment (DPIMS).

The Combustion Module-1 Laminar Soot Processes Experiment and the Structure of Flame Balls at Low Lewis-number Experiment (SOFTBALL).

The Droplet Combustion Experiment (DCE) is designed to investigate the fundamental combustion aspects of single, isolated droplets under different pressures and ambient oxygen concentrations for a range of droplet sizes varying between 2 and 5mm. The DCE apparatus is integrated into a single width MSL Spacelab rack in the cargo bay.

The EXPRESS rack replaces a Spacelab Double rack and special hardware will provide the same structural and resource connections the rack will have on the Space Station. It will house the Physics of Hard Spheres (PHaSE) experiment and the Astro/PGBA Experiment.

The Electromagnetic Containerless Processing Facility (TEMPUS) is used for the Experiments on Nucleation in Different Flow Regimes, Thermophysical Properities of Advanced Materials in the Undercooled Liquid State Experiment, Measurements of the Surface Tension of Liquid and Undercooled Metallic Alloys by Oscillating Drop Technique Experiment, Alloy Undercooling Experiments, the Study of the Morphological Stability of Growing Dendrites by Comparative Dendrite Velocity Measuremetns on Pure Ni and Dilute Ni-C Alloy in the Earth and Space Laboratory Experiment, the Undercooled Melts of Alloys with Polytetrahedral Short-Range Order Experiment, the Thermal Expansion of Glass Forming Metallic Alloys in the Undercooled State Experiment, the AC Calorimetry and Thermophysical Properties of Bulk Glass-Forming Metallic Liquids experiment and the Measurement of Surface Tension and Viscosity of Undercooled Liquid Metals experiment.

There will also be experiments on measuring microgravity. They include the Space Acceleration Measurement System (SAMS), the Microgravity Measurement Assembly (MMA), the Quasi-Steady Acceleration Measurement System and the Orbital Acceleration Research Experiment (OARE).

The Middeck Glovebox (MGBX) facility will support the Bubble and Drop Nonlinear Dynamics (BDND) Experiment, the Study of the Fundamental Operation of a Capillary-driven Heat Transfer (CHT) Device in Microgravity Experiment, the Internal Flows in a Free Drop (IFFD) experiment and the Fiber Supported Droplet Combustion experiment (FSDC-2).


Launch July 1, 1997 2:02:02 pm EST. Launch window was 2 hours 30 min.

On July 1, 1997 at 10:30am, the astronauts departed the O&C building for Launch Pad 39-A and arrived at 10:48am. USAF Weather forcasters and meteorologists with the Spaceflight Meteorology Group(SMG) at the Johnson Space Center in Houston closely tracked KSC's weather.

The crew communications checks were performed at 12:17pm EST and the white room was given the go for to leave the flight deck and prepare for hatch closure. Countdown clock picked up at T-20 minute mark and counting at 13:20pm EST and the close out crew departed LC-39A. At 13:31 the countdown clock entered the hold at the T-9 minute mark. The only concern was a launch commit criteria violation for RTLS weather due to a patch of bad weather to the southwest. The mission management team decided to extend the hold at the T-9 minute mark to give time for the Shuttle Training Aircraft (STA) to take a closer look at the weather systems. At 12:52:07 all teams were given a go for launch and the count came out of the T-5 minute mark at 13:53:00. The gaseous Oxygen vent hood was retracted at T-2 minutes 57 seconds and counting. The crew was given the go to close and lock visors and T-0 occured at 14:02:02 EDT. SRB separation at 2 min 15 seconds and 31 miles downrange. SSME cutoff at 14:10:44 EDT. ET separation at 14:11:13 EDT.

Previously, on Monday, 6/30/97, hoping to preempt expected afternoon thunderstorms, NASA managers had decided to move in the launch time for Columbia by 47 minutes. The 2 1/2 hour launch window was at 2:37pm EST but was rescheduled to open at 1:50 p.m. The decision to launch early removed one end of mission daylight landing opportunity at Edwards Air Force Base, CA, but still allowed two daylight landing opportunities at KSC. The Rotating Service Structure was retracted to the launch position at about 8:30 p.m. and loading of the external tank with cryogenic propellants began at about 4:47 a.m. on July 1, 1997.

Loading of the external tank with cryogenic propellants is scheduled to begin at about 5:45 a.m. Tuesday. The astronauts will depart the crew quarters for the launch pad at 11:17 a.m. and begin boarding Columbia about a half hour later. The hatch will be closed and sealed at 1:07 p.m., leading to launch at 2:37 p.m. Air Force weather forecasters are currently indicating a 90 percent probability of weather prohibiting launch of Columbia on July 1. The concern is for thunderstorms and associated rain, wind and lightning. Given the possibility of severe weather during Tuesday's launch attempt, managers may elect to postpone the opening of the launch window by up to two hours. If this option is selected, the decision will be reached by late Monday afternoon.
On Sunday, the launch pad was closed for a checkout of the firing chain and the Space Shuttle onboard ordnance systems. This was followed by the loading of cryogenic reactants into the onboard fuel cell storage tanks located beneath the payload bay. The fuel cells generate power for Columbia and the Microgravity Science Laboratory during the 16-day mission. The reactant loading started on schedule at 11 a.m. and because of the extended duration of the mission, it took approximately 12 hours to complete instead of the usual eight hours.

On Saturday, 6/28/97, the countdown for the launch of Space Shuttle Columbia and the reflight of the Microgravity Science Laboratory began on schedule today at 3 p.m. EDT. The STS-94 astronauts arrived at the Shuttle Landing Facility in their T-38 jet trainers at 12:25 p.m.

On Wednesday, 6/25/97, at the launch pad, ordnance installation was completed and testing of the pyrotechnic initiator controllers was underway. Work to close-out Columbia's aft compartment picked-up and continues through Friday. Installation of the fabricated "pyro can" assemblies at the orbiter's external tank attach points continued. Launch countdown preparations also continue with hypergolic propellant pressurization in work.

On Friday, 6/20/97, loading of storable hypergolic propellants aboard Columbia continued. Tile installation work on the forward reaction control system was completed, with all 36 tiles bonded to the vehicle. Bond verification checks will begin after the loading of hypergolic propellants. In Columbia's aft compartment, work to install the fabricated "pyro can" assemblies at the orbiter's external tank attach points concludes Saturday.

On Thursday, 6/19/97, following the STS-94 Flight Readiness Review, NASA managers announced July 1 as the official launch date for Columbia's reflight of the Microgravity Science Laboratory-1 mission.

On Tuesday, 6/17/97, work to connect the orbiter's mid-body umbilical unit, used to load cryogenic reactants aboard the orbiter was completed and tile work on the forward reaction control system continued. Of the 36 tiles slated for replacement at the pad, 28 had been installed. The helium signature leak test was in work and loading of the storable hypergolic propellants aboard Columbia was scheduled for Thursday. Repair work to wiring in avionics bay No. 4 continues through Wednesday.

On Friday, 6/13/97 The main engine flight readiness test was successfully completed. Work continued to replace 36 Thermal Protection System tiles on Columbia's forward Reaction Control System. Shuttle technicians raised the concern of possible cracked tiles during routine inspections of the FRCS. Evaluations of the FRCS tiles on the entire Shuttle fleet helped engineers decide to replace the tiles with stronger ones. Preparations began for the hypergolic propellant loading and repair work to wiring in avionics bay No. 4 resumed.

On Tuesday, 6/10/97, in the VAB, Columbia is mated to the external tank and mating close-outs were in work. Rework on spliced wires in the Shuttle's avionics bay were underway and electrical evaluations of a controller check-out unit for auxiliary power unit No. 2 were also in work. NASA's plan to eventually use a super lightweight external fuel tank requires modification to an orbiter's tail service mast. Columbia's tail service mast underwent retraction tests over the weekend to assist engineers in that effort. Over the weekend, additional thermal protection tiles were removed from the orbiter's forward reaction control system. More than 30 suspect tiles have been removed because of cracks seen during recent inspections. Evaluations of the FRCS tiles on the other orbiters have resulted in the removal of several tiles from orbiters Discovery and Atlantis. Stronger tiles will replace those that were removed from each orbiter and the majority of Columbia's tile replacement work will be done at the pad. Managers are working on a plan to complete the tile work in time for the July 1 launch date.

On Monday, 6/2/97, Columbia's payload bay doors were closed for flight and the following day technician wrapped up close-out work in the orbiter's aft compartment and performed some tile work on nose of the vehicle. Preparations were in work for the orbiter's move to the Vehicle Assembly Building (VAB) targeted for 6/4/97 at about 11 a.m. The external tank and solid rocket boosters await Columbia in VAB high bay 1 for a hard mate to be completed on Thursday, 6/5/97. Once in the VAB, wiring work will continue in the Shuttle's avionics bay 4 and electrical check-outs of an auxiliary power unit will pick-up.

On 5/29/97, inspections of Columbia's forward Reaction Control System (RCS) revealed cracks in several thermal protective tiles in that vicinity. Work to replace those tiles will be performed at the pad and have no impact on the roll out schedule. Due to additional wiring work in Columbia's cargo bay, close-outs continue in the orbiter's mid-body. The spacelab transfer tunnel is now scheduled for installation Friday 5/30/97 and Columbia's roll to the Vehicle Assembly Building (VAB) will likely occur on June 5.

On 5/23/97, ammonia servicing was complete. Heat shield installation continues through the night and the Water Spray Boiler servicing is in work. While working close-outs in Columbia's mid-body, technicians noted cracks in two fuse holders that are part of the orbiter's power distribution system. As a result, work to repair a power distribution assembly and replacement of a power controller assembly will begin this weekend. The additional work in the mid-body will likely delay the installation of the Spacelab transfer tunnel until next week. Managers are assessing what impact if any the additional work will have on remaining OPF milestones. No impact to the overall pad schedule is expected.

On 5/20/97, heat shield installation continued as well as work to connect Auxiliary Power Unit (APU) fuel lines. Over the weekend, technicians noted a frayed pyrotechnic cable in the orbiter's cargo bay. Work continues in the orbiter's midbody to repair a frayed pyrotechnic cable. The Spacelab transfer tunnel will be installed on Friday. Payload technicians are troubleshooting a remote acquisition unit on Spacelab today.

On 4/25/97, On Friday, Shuttle managers officially announced that Columbia would refly the shortened STS-83 mission in early July. For planning purposes, the reflight mission was internally called STS-83R but now has the official designation STS-94. Replacement of two thrusters on Columbia's forward reaction control system (FRCS) was completed. Electrical hook-up work continues on the FRCS in the Hypergol Maintenance Facility. The FRCS should return to the OPF in early May to be reinstalled on the orbiter. Postflight work on Columbia's auxiliary power units continues through Tuesday, 4/29/97. Spacelab reservicing activities also continue.

On 4/25/97, thruster replacement work continued on Columbia's forward Reaction Control System (RCS) in the Hypergol Maintenace Facility. The forward RCS should return to the OPF in early May to be reinstalled on the orbiter. Postflight work on Columbia's Auxiliary Power Units (APU's) continues through Tuesday. Spacelab reservicing activities also continue. STS-83R booster stacking operations continue in the Vehicle Assembly Building. Right forward center segment mating activities are in work today.

On 4/17/97, fuel cell No. 1 leak checks will conducted. Preparations continue for main engine removal on Friday 4/18/97 and Saturday 4/19/97. Forward reaction control system functional tests were completed 4/16/97 and FRCS removal is scheduled for 4/18/97. Removal of the Spacelab tunnel is in work and Spacelab reservicing will begin. In the VAB, the booster segments originally intended for use on STS-85 are being stacked for use on STS-83R. Work to mate the left forward center segment to the left aft center segment is scheduled for 4/17/97. The left forward segment should arrive in the VAB as well.


Altitude: 184 statute miles
Inclination: 28.45
Orbits: 251
Duration: 15 days, 16 hours, 46 minutes, seconds.
Distance: 6.2 million miles


ET : ET-86
SSME-1: SN-2037
SSME-2: SN-2034
SSME-3: SN-2033


KSC 7/17/1997 6:47am EDT. Shuttle Landing Facility Runway 33. Main Gear Touchdown: 15days 16hours 44min 34sec (6:46:34am EDT), Nose Wheel Touchdown: 15days 16hours 44min 45sec (6:46:45am EDT). Wheel Stop: 15days 16hours 45min 29sec (6:47:29am EDT).

A go was given for the deorbit burn at 5:38am EST on orbit 250 with at landing on orbit 251. The 3min 1sec burn at 05:43 provided a delta change in velocity of 298.7 ft/sec. This burn placed Columbia in a 163x12nm orbit and allowed the vehicle to drop out of orbit 4,300 miles from landing site. Weather at the landing strip had a visibility of 8 miles 2 knot winds with a temperature of 72 degrees and 98 percent relative humidity.

Weather was expected to be favorable for both landing opportunities, although the first still had a slight chance of some pre-dawn ground fog developing that would not dissipate in time of the decision to land. As the sun heats the atmosphere, the ground fog dissipates rather quickly presenting more favorable weather. Had a second opportunity been needed, landing would have been at 8:22 a.m. EST. Columbia's next mission is STS-87.

Mission Highlights:

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