NASA will begin the countdown for launch of Space Shuttle Discovery
on mission STS-105 Aug. 6 at 5 p.m. EDT at the T-43 hour mark. This mission
marks the 11th Shuttle flight to the International Space Station and the 5th
Shuttle mission this year. The KSC launch team will conduct the countdown
from Firing Room 3 of the Launch Control Center.

The countdown includes 29 hours and 32 minutes of built-in hold time
leading to a preferred launch time at about 5:38 p.m. on Aug. 9 with a
launch window not to exceed 5 minutes. The exact location of the orbiting
International Space Station (ISS) will be determined during the T-9 minute
built-in hold. The launch director will at that time determine the exact
time of launch.

Mission STS-105 is the 30th flight of the orbiter Discovery and the 106th
flight overall in NASA’s Space Shuttle program. STS-105 is scheduled to last
about 12 days with a planned KSC landing at about 1:17 p.m. on Aug. 21.

Discovery rolled into KSC’s Orbiter Processing Facility on March 21,
2001, after completing mission STS-105. The orbiter rolled out of OPF bay 2
and into the VAB on June 13. While in VAB high bay 3, Discovery was mated to
the external tank and solid rocket boosters. The entire Space Shuttle stack
was transferred to Launch Pad 39A on July 2.

On mission STS-105, the seven-member crew will berth the 4.5-ton
Leonardo Multi-Purpose Logistics Module (MPLM) to the International Space
Station. Leonardo, which will be used to carry laboratory racks filled with
equipment, experiments and supplies to and from the Station, will be
attached to the Station using the Shuttle’s robot arm. The Early Ammonia
Servicer (EAS) tank, which will provide intermediate ammonia resupply to the
Station’s cooling system, will be installed during two spacewalks. The
three-member Expedition Two ISS crew will return to Earth following eight
days of docked operations and will be replaced by the three-member
Expedition Three crew.

The STS-105 crew includes Commander Scott Horowitz, Pilot Rick
Sturckow, and Mission Specialists Patrick Forrester and Daniel Barry, as
well as Frank Culbertson, Vladimir Nikolaevich Dezhurov and Mikhail Tyurin,
the Expedition Three crew members.

(end of general release)

COUNTDOWN MILESTONES

*all times are Eastern

Launch-3 Days (Monday, Aug. 6)

  • Prepare for the start of the STS-105 launch countdown
  • Perform the call-to-stations (4:30 p.m.)
  • Countdown begins at the T-43 hour mark (5 p.m.)
  • Begin final vehicle and facility close-outs for launch
  • Check out back-up flight systems
  • Review flight software stored in mass memory units and display
    systems

  • Load backup flight system software into Discovery’s general purpose
    computers

  • Launch-2 Days (Tuesday, Aug. 7)

  • Remove mid-deck and flight-deck platforms (12 a.m.)
  • Activate and test navigational systems (10 a.m.)
  • Complete preparation to load power reactant storage and distribution
    system (1 p.m.)

  • Flight deck preliminary inspections complete (1 p.m.)
  • Enter first built-in hold at T-27 hours for duration of 8 hours (9
    a.m.)

  • Clear launch pad of all non-essential personnel
  • Perform test of the vehicle’s pyrotechnic initiator controllers (2
    p.m.)

  • Resume countdown (5 p.m.)
  • Begin operations to load cryogenic reactants into Discovery’s fuel
    cell storage tanks

  • (5 p.m. – 12 a.m.)

    Launch-1 Day (Wednesday, Aug. 8)

  • Enter 4-hour built-in hold at T-19 hours (1 a.m.)
  • Demate orbiter mid-body umbilical unit (1:30 a.m.)

    Resume countdown (5 a.m.)

  • Final preparations of the Shuttle’s three main engines for main
    propellant tanking and flight (5 a.m.)

  • Begin filling pad sound suppression system water tank (7:30 a.m.)
  • Resume orbiter and ground support equipment close-outs
  • Pad sound suppression system water tank filling complete (12:30
    p.m.)

  • Close out the tail service masts on the mobile launcher platform

    Enter planned hold at T-11 hours for 12 hours, 42 minutes (1 p.m.)

  • Begin star tracker functional checks (1:30 p.m.)
  • Activate orbiter’s inertial measurement units
  • Activate the orbiter’s communications systems
  • Install film in numerous cameras on the launch pad (3:30 p.m.)
  • Flight crew equipment late stow (5:30 p.m.)
  • Move Rotating Service Structure (RSS) to the park position (9:30
    p.m.)

  • Perform ascent switch list
  • Fuel cell flow-through purge complete
  • Launch Day (Thursday, Aug. 9)
  • Resume countdown at T-11 hours (1:42 a.m.)
  • Activate the orbiter’s fuel cells (2:52 a.m.)
  • Clear the blast danger area of all non-essential personnel
  • Switch Discovery’s purge air to gaseous nitrogen (3:57 a.m.)
  • Enter planned 2-hour built-in hold at the T-6 hour mark (6:42 a.m.)
  • Launch team verifies no violations of launch commit criteria prior
    to cryogenic loading of the external tank

  • Clear pad of all personnel
  • Chilldown of propellant transfer lines (8:12 a.m.)
  • Begin loading the external tank with about 500,000 gallons of
    cryogenic propellants (about 8:42 a.m.)

  • Resume countdown (8:42 a.m.)
  • Complete filling the external tank with its flight load of liquid
    hydrogen and liquid oxygen propellants (about 11:42 a.m.)

  • Final Inspection Team proceed to launch pad
  • Enter planned 2-hour built-in hold at T-3 hours (11:42 a.m.)
  • Perform inertial measurement unit preflight calibration
  • Align Merritt Island Launch Area (MILA) tracking antennas
  • Perform open loop test with Eastern Range
  • Resume countdown at T-3 hours (1:42 p.m.)
  • Crew departs Operations and Checkout Building for the pad (1:47
    p.m.)

  • Complete close-out preparations in the white room
  • Check cockpit switch configurations
  • Flight crew begins entry into the orbiter (about 2:17 p.m.)
  • Astronauts perform air-to-ground voice checks with Launch and
    Mission Control

  • Close Discovery’s crew hatch (about 3:32 p.m.)
  • Begin Eastern Range final network open loop command checks
  • Perform hatch seal and cabin leak checks
  • Complete white room close-out
  • Close-out crew moves to fallback area
  • Primary ascent guidance data is transferred to the backup flight
    system

  • Enter planned 10-minute hold at T-20 minutes (4:22 p.m.)
  • NASA Test Director conducts final launch team briefings
  • Complete inertial measurement unit preflight alignments
  • Resume countdown at T-20 minutes (4:32 p.m.)
  • Transition the orbiter’s onboard computers to launch configuration
  • Start fuel cell thermal conditioning
  • Close orbiter cabin vent valves
  • Transition backup flight system to launch configuration
  • Enter estimated 40-minute hold at T-9 minutes (4:43 p.m.)
  • Launch Director, Mission Management Team and NASA Test Director
    conduct final polls for go/no go to launch

  • Resume countdown at T-9 minutes (about 5:23 p.m.)
  • Start automatic ground launch sequencer (T-9:00 minutes)
  • Retract orbiter crew access arm (T-7:30)
  • Start mission recorders (T-6:15)
  • Start Auxiliary Power Units (T-5:00)
  • Arm SRB and ET range safety safe and arm devices (T-5:00)
  • Start liquid oxygen drainback (T-4:55)
  • Start orbiter aerosurface profile test (T-3:55)
  • Start main engine gimbal profile test (T-3:30)
  • Pressurize liquid oxygen tank (T-2:55)
  • Begin retraction of the gaseous oxygen vent arm (T-2:55)
  • Fuel cells to internal reactants (T-2:35)
  • Pressurize liquid hydrogen tank (T-1:57)
  • Deactivate SRB joint heaters (T-1:00)
  • Orbiter transfers from ground to internal power (T-0:50 seconds)
  • Ground Launch Sequencer go for auto sequence start (T-0:31 seconds)
  • SRB gimbal profile (T-0:21 seconds)
  • Ignition of three Space Shuttle main engines (T-6.6 seconds)
  • SRB ignition and liftoff (T-0)

    SUMMARY OF BUILT-IN HOLDS FOR STS-105

        T-TIME            LENGTH OF HOLD        HOLD BEGINS        HOLD ENDS
    T-27 hours	8 hours	9 a.m. Tues.	5 p.m. Tues.
    T-19 hours	4 hours	1 a.m. Wed. 	5 a.m. Wed.
    T-11 hours	12 hours, 42 minutes	1 p.m. Wed.	1:42 a.m. Thurs.
    
    T-6 hours	2 hours	6:42 a.m. Thurs.	8:42 a.m. Thurs.
    T-3 hours	2 hours	11:42 a.m. Thurs.	1:42 p.m. Thurs.
    T-20 minutes	10 minutes	4:22 p.m. Thurs.	4:32 p.m. Thurs.
    
    T-9 minutes	about 40 minutes	4:43 p.m. Thurs. 	5:23 p.m.
    Thurs.
    

    CREW FOR MISSION STS-105

    Commander (CDR): Scott Horowitz

    Pilot (PLT): Rick Sturckow

    Mission Specialist 1: Patrick Forrester

    Mission Specialist 2: Daniel Barry

    Expedition Three CDR: Frank Culbertson

    Expedition Three: Mikhail Tyurin

    Expedition Three: Vladimir Dezhurov

    SUMMARY OF STS-105 LAUNCH DAY CREW ACTIVITIES

    Thursday, August 9

    7:30 a.m. Crew wake up

    8 a.m. Breakfast

    9:30 a.m. Medical checks

    12:00 p.m. Lunch

    *12:30 p.m. Photo opportunity

    1:07 p.m. Weather Briefing (CDR, PLT, MS2)

    1:07 p.m. Don flight suits (MS1, MS3, MS4, MS5)

    *1:17 p.m. Don flight suits (CDR, PLT, MS2)

    *1:47 p.m. Depart for launch pad

    *2:17 p.m. Arrive at white room and begin ingress

    *3:32 p.m. Close crew hatch

    *5:38 p.m. Launch

    * Televised events (times may vary slightly)
    All times Eastern