Launch Coverage

    Welcome to the STS-118 Launch Blog
    Space Shuttle Endeavour lifted off from Kennedy Space Center's Launch Pad 39A at 6:36 p.m. EDT on Aug. 8, 2007, beginning the STS-118 mission. This is how the launch countdown unfolded.

    Activated: 12 p.m. EDT
    Deactivated: 6:50 p.m. EDT

    Video Gallery
    Video highlights from the STS-118 countdown were selected from televised coverage provided by NASA TV.
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    Note: All times are given in Eastern (EDT) unless otherwise noted.
    6:50 p.m. - Space Shuttle Endeavour and a crew of seven astronauts have reached orbit, capping a flawless three-day countdown and a spectacular late-afternoon launch. The mission is only beginning, so check the Space Shuttle Web site each day for the latest news, and be sure to join us on landing day for the Landing Blog.

    This is NASA's Launch Blog, signing off.

    6:46 p.m. - MECO! Booster officer confirms main engine cutoff and a good external tank separation. Endeavour is in its preliminary orbit. "For Barbara Morgan and her crewmates, class is in session," remarked NASA Commentator Rob Navias from Mission Control in Houston.

    6:42 p.m. - Now five minutes into flight, Endeavour has three good main engines, three good APUs and three good fuel cells, reports Mission Control.

    6:38 p.m. - And a good solid rocket booster separation. Endeavour is climbing toward a date with the International Space Station and all is going well with the flight as the orbiter's three main engines power the vehicle through Earth's atmosphere.

    6:36 p.m. - Liftoff of Space Shuttle Endeavour!

    Endeavour is rolling into a head-down position as it climbs skyward, with its wings level and aligned with the launch pad. About half a minute after liftoff, the shuttle's three main engines throttle down to about 72 percent, then throttle back up to 104 percent one minute into flight, as the vehicle approaches the peak of aerodynamic pressure called "max Q."

    The shuttle's twin solid rocket boosters will burn out and separate about two minutes into flight.

    6:31 p.m. - The Orbiter Access Arm has been retracted and prestart of Endeavour's three auxiliary power units, or APUs, is complete. In a moment, the units will be activated along with data recorders in the Firing Room.

    6:28 p.m. - T-9 minutes and counting! In just nine minutes, Space Shuttle Endeavour will begin its first mission since 2002. Here at Kennedy Space Center's Launch Complex 39 Press Site, employees and reporters have quieted with anticipation as they get into position for the perfect view of liftoff.

    6:26 p.m. - Mission Management Team Chairman LeRoy Cain and NASA Test Director Jeff Spaulding polled both their teams, followed by a final poll by Launch Director Mike Leinbach. Endeavour is "go" for launch!

    "Endeavour, Launch Director," Leinbach called up to Commander Scott Kelly. "Okay, Scott, the weather is great, Endeavour is ready to fly after four-and-a-half years, so good luck, Godspeed and have some fun up there."

    6:11 p.m. - Weather is now "green," for acceptable for launch, at all three transoceanic abort sites. Everything is in order for launch this evening and the clock will begin ticking down from T-9 minutes at 6:28 p.m.

    6:05 p.m. - The STS-118 mission is currently scheduled as an 11-day mission with three spacewalks planned, but mission managers could add three more days and an additional spacewalk after the Station-Shuttle Power Transfer System (SSPTS) is activated and checked out.

    5:52 p.m. - With the flight crew safely strapped into their seats and Endeavour's crew access hatch securely closed, the Closeout Crew is getting ready to leave the White Room and head to its station a safe distance away.

    5:42 p.m. - T-9 minutes and holding. This is the final built-in hold and will last 41 minutes, 52 seconds. At this point, the countdown is running on time and launch is on track for 6:36 p.m.

    5:31 p.m. - T-20 minutes and counting. There's one planned hold left in today's countdown, at T-9 minutes.

    5:28 p.m. - NASA Test Director Jeff Spaulding is giving launch personnel his final instructions for the remainder of the countdown. Today's launch window opens at 6:32:52 p.m. and closes at 6:43:46 p.m., and the preferred launch time comes in the middle of the window at 6:36:42 p.m.

    5:23 p.m. - Good news: The launch team has verified that Endeavour's crew access hatch is closed. With this issue behind us, cabin leak checks are under way.

    5:21 p.m. - T-20 minutes and holding for 10 minutes.

    5:15 p.m. - There are two technicians in the White Room working to confirm that Endeavour's crew hatch is securely closed. Stand by for updates.

    5:08 p.m. - The Mission Management Team just wrapped up a discussion about a small crack in the external tank foam near the liquid oxygen feedline support bracket. Team members have concluded that there is no debris issue regarding the crack and the tank is safe. Meanwhile, the Closeout Crew is continuing to work with the crew access hatch, trying to verify that the hatch is indeed closed.

    4:52 p.m. - The Closeout Crew members have run into a problem with "micro" switches associated with the crew hatch. They're going to start over by re-opening and closing the hatch once again in an effort to get a good latch and seal.

    4:41 p.m. - T-1 hour and counting down toward launch of Space Shuttle Endeavour at 6:36 p.m. There are two more holds planned in the countdown. At T-20 minutes, the clock will hold for 10 minutes, and at T-9 minutes, the clock will hold again for about 42 minutes.

    4:30 p.m. - The Closeout Crew just received the go-ahead to close the crew access hatch. With the hatch closed, the white-suited Closeout Crew personnel will check for leaks, vent the cabin and close the vent valves.

    4:21 p.m. - The astronauts' comm checks are complete and it's time for the Closeout Crew members to finish their work inside Endeavour's crew module and start closing the hatch.

    4:01 p.m. - Now that Mission Specialist Rick Mastracchio has climbed into his seat, all seven crew members are on board and finishing their comm checks. At T-1 hour, 40 minutes and counting, the countdown continues to go quite well.

    3:50 p.m. - Mission Specialists Tracy Caldwell and Barbara Morgan are in the process of strapping into their seats. Mission Specialist Rick Mastracchio is the only crew member not yet on board.

    3:44 p.m. - More good news on the weather. Forecasters are removing isolated showers from this evening's forecast, according to Shuttle Weather Officer Kathy Winters, so the chance of weather preventing launch tonight has dropped to only 10 percent.

    3:38 p.m. - As the astronauts are strapped in, they begin "comm checks," verifying that they are all able to communicate easily with the launch team at Kennedy and Mission Control personnel in Houston. This is a standard part of the boarding process.

    3:30 p.m. - At T-2 hours, 11 minutes and counting, Commander Scott Kelly, Pilot Charlie Hobaugh and Mission Specialists Alvin Drew and Dave Williams are already seated inside Endeavour. Inside the White Room, Mission Specialists Tracy Caldwell and Barbara Morgan are making final boarding preparations with the help of Closeout Crew members.

    3:05 p.m. - The astronauts have arrived at Launch Pad 39A and will soon begin climbing through the hatch into Endeavour's crew module. They have specific seating designations for launch, and the assignments often change for landing. All seven will be on board and strapped in by about 4 p.m.

    2:56 p.m. - Here at the Launch Complex 39 Press Site -- where the Launch Blog is based -- the sound of the helicopter escorting the Astrovan signals that the crew is passing by on the way to the launch pad. After the brief stop at the Launch Control Center, the only people remaining in the van are the astronauts, a suit technician, and the driver.

    2:50 p.m. - The Astrovan makes two stops during the trip to the launch pad. At the first stop, astronaut Mark Polansky will exit the van, climb into a waiting car and head to the Shuttle Landing Facility to begin weather-monitoring flights. A few minutes later, the van will stop again in front of the Launch Control Center to drop off Chief Astronaut Steve Lindsey and astronaut Jerry Ross, chief of the Vehicle Integration Test Office at Johnson Space Center, Houston.

    2:46 p.m. - They're on their way! Waving and smiling, the seven astronauts soon to board Space Shuttle Endeavour are walking out of the Operations & Checkout Building, which houses their crew quarters. As usual, many employees have gathered to cheer for the crew members as they board the silver Astrovan and depart for the pad. Today's countdown remains problem-free, with weather and hardware cooperating. We're still on target for liftoff at 6:36 p.m.

    2:41 p.m. - T-3 hours and counting. The flight crew members, led by Commander Scott Kelly, are due to depart the Operations & Checkout Building for Launch Pad 39A in about five minutes.

    2:22 p.m. - Inside the suit-up room at the Astronaut Crew Quarters, the STS-118 crew members are all smiles as technicians help them climb into their orange launch-and-entry suits. Joining them is astronaut Mark Kelly, twin brother of STS-118 Commander Scott Kelly. The astronauts will wear these suits during liftoff today as well as during their return to Earth several days from now. Once they're suited up, they'll depart for the launch pad. There are less than 20 minutes remaining in the T-3 hour built-in hold.

    2:00 p.m. - The STS-118 mission will be the last mission for SPACEHAB, which is carrying some 5,800 pounds of equipment and supplies to the International Space Station.

    1:26 p.m. - The Ice Team has completed its inspection and is departing Launch Pad 39A.

    1:15 p.m. - The countdown clock is still holding at T-3 hours. This is a built-in hold scheduled to last three hours, until 2:41 p.m. On the surface of the mobile launcher platform at the base of Space Shuttle Endeavour, the Ice Team members are easily visible in their bright-orange suits as they continue their top-to-bottom inspection.

    In Firing Room 4 of the Launch Control Center, launch team personnel are moving steadily through their countdown checklists. The countdown is still going quite smoothly, with no issues reported.

    12:44 p.m. - The astronauts just finished a light snack before heading to the suit-up room. The weather continues to look good for launch this evening, including at two of NASA's three transoceanic abort landing sites, or TAL sites. Spain's Zaragoza and Moron landing sites are favorable while the site at Istres, France is not.

    12:35 p.m. - The Closeout Crew is continuing its work inside the launch pad's climate-controlled White Room. They're assisted by the Astronaut Support Personnel, or ASPs, although they're affectionately known as the "Cape Crusaders." Astronaut Kay Hire is the prime ASP today, with additional support provided by astronauts Butch Wilmore, Jose Hernandez, Joe Acaba, and Marsha Ivins.

    12:15 p.m. - The Ice Team members have reached the launch pad's 135-foot level. They began their two-hour inspection at the top of the pad, at the 255-foot level, and are systematically making their way down to the surface of the mobile launcher platform. They're using binoculars and even telescopes as they look for ice, frost or debris that could threaten the shuttle during liftoff.

    12:00 p.m. - T-3 hours and holding. For Space Shuttle Endeavour and the seven-member STS-118 crew, launch day has finally arrived. Launch remains on schedule for 6:36 p.m. this evening, and the excitement and tension are building at NASA's Kennedy Space Center in Florida, where the countdown has proceeded quite smoothly.

    Today's forecast is remarkably favorable, with only a 20-percent chance of weather preventing liftoff. Florida summers usually bring afternoon storms, so the good break in today's weather is a welcome change for the launch team.

    One major launch milestone -- "tanking," the filling of Endeavour's orange external tank with 500,000 gallons of liquid oxygen and liquid hydrogen -- is complete. Tanking began at 8:11 a.m. and wrapped up at about 11 a.m. Both propellants are now in stable replenish until the final minutes of today's countdown.

    The Final Inspection Team, or "Ice Team," reached the launch pad at 11:20 a.m. and began its detailed inspection of the shuttle and pad. Likewise, members of the Orbiter Closeout Crew have reached the White Room, where they're making final preparations before the flight crew climbs aboard this afternoon. The astronauts, meanwhile, are getting ready to sit down for one more Earthbound meal before suiting up for flight.

    We're glad you've chosen NASA's Launch Blog to guide you through today's countdown. It's going to be an exciting afternoon, so stick with us.

    Live Coverage Team
    Blog Updates: Anna Heiney
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