Showing posts with label spacewalks. Show all posts
Showing posts with label spacewalks. Show all posts

Crew Readies for Resupply Ship and Upcoming Departure

http://nasa-spacestation-info.blogspot.com/The Expedition 24 crew members are preparing for the arrival of the ISS Progress 39 cargo craft to replenish the orbiting laboratory with food, fuel, supplies and other cargo. The Progress 39 will dock to the aft end of the Zvezda service module Friday, Sept. 10. It is replacing the trash-filled Progress 38 which undocked Aug. 31 and is poised to re-enter Earth’s atmosphere Monday for a fiery destruction over the Pacific Ocean.

The crew also will have an off-duty day Monday due to a frenetic pace of science activities. The six crew members are relaxing after three repair spacewalks restored the station’s cooling system.
http://nasa-spacestation-info.blogspot.com/
Hurricane activity captured the attention of the station residents as they photographed and videotaped Earl churning in the Atlantic Ocean. The imagery and video are downlinked to ground controllers for observation and study by scientists. A Russian experiment, Uragan (Hurricane), monitors and studies the catastrophic effects of natural and man-made disasters. Other ongoing Earth observation experiments aboard the orbiting laboratory study natural phenomena and human activities and their consequences on the planet.

Commander Alexander Skvortsov and Flight Engineers Mikhail Kornienko and Tracy Caldwell Dyson are nearing the end of their stay at the International Space Station. They are scheduled to undock Sept. 23 in their Soyuz TMA-18 for a landing in Kazakhstan a few hours later. Their undocking will mark the official end of Expedition 24 and the beginning of Expedition 25.

In preparation, Skvortsov and Kornienko set up and charged an Iridium satellite phone inside their Soyuz capsule. The phone would be used as a backup if the Soyuz crew was out of communications range with their landing support team. The departing crew also began stowing gear for the return home.

In Star City, Russia their replacements – Expedition 25 Flight Engineers Scott Kelly, Alexander Kaleri and Oleg Skripochka – are preparing for their mission beginning in October. About two weeks after Expedition 24 lands, they will launch in a new, more advanced Soyuz vehicle, the Soyuz TMA-01M. The new Soyuz will feature an updated computer and telemetry system.


The three new crew members will join Expedition 25 Commander Doug Wheelock and Flight Engineers Shannon Walker and Fyodor Yurchikhin. The orbiting trio has been aboard the station since June 17 when they joined Expedition 24 after arriving in the Soyuz TMA-19 spacecraft.

Caldwell Dyson worked on a fluid connection inside the European Columbus laboratory noting some corrosion and possible leakage. She worked with the Columbus Control Center in Munich, Germany to troubleshoot and photograph a valve behind the lab's EXPRESS Rack 3 that proved difficult to open and close.

Walker audited emergency provisions including a portable fire extinguisher and breathing apparatus. The twice yearly inspection involves documenting serial numbers, barcodes and locations of gear.

Wheelock and Yurchikhin set up the ongoing Kids-In-Space experiment. The station crew members along with students and teachers on Earth explore differences in physical phenomena on Earth and in microgravity. One familiar experiment involves a filling a bottle with water at different levels and blowing across the top to determine if it would sound any different in space.

International Space Station Repair Spacewalk Planned for Friday


Spacewalks Set for Friday and Monday

Activities aboard the International Space Station remained focused on spacewalk preparations Tuesday as the Expedition 24 crew gets ready to replace a failed ammonia pump module that took down half the station’s cooling system over the weekend.

Expedition 24 astronauts Doug Wheelock and Tracy Caldwell Dyson, both flight engineers, currently are scheduled to start the repairs Friday during the first of two spacewalks. Mission managers, program managers, flight controllers, engineers, astronauts and spacewalk experts rescheduled the spacewalk, originally planned for Thursday, after continuing to analyze and refine engineering requirements, and reviewing the results of an underwater practice session.

Fellow astronauts Cady Coleman and Suni Williams spent Monday afternoon in the Johnson Space Center’s Neutral Buoyancy Laboratory practicing underwater the tasks needed to restore the cooling loop over the course of two spacewalks.

Meanwhile, robotics experts are continuing to refine the procedures that will be used by Flight Engineer Shannon Walker to guide the station’s robotic arm, Canadarm2, as she moves Wheelock into position to swap the failed unit with a spare unit currently stored on External Stowage Platform 2. That spare parts carrier is attached to the Quest airlock that Wheelock and Caldwell Dyson will use to exit and reenter the station.

The station remains in a stable configuration. The crew is on a normal sleep shift, and supporting a normal workday, but most of the planned activities this week have been cancelled or deferred in order to support spacewalk preparations.

Wheelock, Caldwell Dyson and Walker reviewed spacewalk procedures Tuesday, taking a look at the activities to be performed during the excursion as well as familiarizing themselves with the steps needed to decontaminate the spacesuits should ammonia crystals seep out of the pump module connectors.

Also on Tuesday the station’s Mobile Transporter was commanded to move to the Starboard 1 truss. With the Mobile Transporter in position, the ground team will be able to gather additional data to confirm power resources are sufficient for Canadarm2 to support the spacewalk.

Each pump module weighs 780 pounds and is 5 ½ feet long (69 inches) by 4 feet wide (50 inches), and is 3 feet tall (36 inches). The spacewalkers will need to disconnect and reconnect five electrical connectors, four fluid quick-disconnect devices, one fixed grapple bar and four bolts. The spare pump module that will be used to replace the failed unit was delivered to the station on the STS-121/Utilization Logistics Flight-1 mission in July 2006.

The pump failed Saturday night after a spike in electrical current tripped a circuit breaker. When the 780-pound pump failed, it shut down half of the station’s cooling system. Efforts to restart the pump, which feeds ammonia coolant into the cooling loops to maintain the proper temperature for the station’s electrical systems and avionics, were not successful. The station’s crew worked with Mission Control to put the station in a stable configuration.

NASA TV coverage will begin at 6 a.m. EDT Friday and Wheelock and Caldwell Dyson will begin the spacewalk at 6:55 a.m. In the first spacewalk, they will unbolt and remove the failed pump module, and install the spare. A second spacewalk to hook up a variety of electrical and fluid connections for the new pump module is targeted for Monday.

Wheelock, who will be designated as EV1, or extravehicular crew member 1, wearing the spacesuit bearing the red stripes, will be making the fourth spacewalk of his career, while Caldwell Dyson, designated as EV2, wearing the unmarked spacesuit, will be making her first spacewalk.

Wheelock and Caldwell Dyson originally were scheduled to perform a spacewalk to outfit the Russian Zarya module for future robotics work and prepare the station for the installation of a new U.S. permanent multipurpose module. However, because of the importance of restoring redundancy to the station's cooling and power systems, the two new spacewalks will be dedicated to the pump module replacement.

Analysis, Spacewalk Preparations Continue After Loss of Cooling Loop on Space Station

Analysis, Spacewalk Preparations Continue After Loss of Cooling Loop
Teams of flight controllers are continuing engineering analysis and refining procedures to replace a failed International spacewalkSpace Station ammonia pump module later this week. Expedition 24 astronauts Doug Wheelock and Tracy Caldwell Dyson currently are scheduled to start the repairs on the station’s starboard truss Thursday.

A briefing to discuss the current station status and to preview the upcoming spacewalks will be broadcast on NASA Television at 4 p.m. EDT today. Briefers will include Michael Suffredini, the International Space Station Program Manager, and Flight Director Courtenay McMillan, who will lead the team supporting the spacewalks.

The pump failed Saturday night after a spike in electrical current tripped a circuit breaker. When the 780-pound pump failed, it shut down half of the station’s cooling system. Efforts to restart the pump, which feeds ammonia coolant into the cooling loops to maintain the proper temperature for the station’s electrical systems and avionics, were not successful. The station’s crew worked with Mission Control to put the station in a stable configuration. The crew, which is in no danger, has resumed normal work activities. A tag-up to review procedures with spacewalk specialists is planned later today.

On Wednesday, flight controllers plan to move the Mobile Transporter, which will be used to support robotics operations for the spacewalks, into position at the replacement worksite.

Current planning continues to support an initial spacewalk on Thursday beginning just before 7 a.m. by Wheelock and Caldwell Dyson to unbolt and remove the failed pump module, and to install the spare. NASA TV coverage will begin at 6 a.m. A second spacewalk to hook up a variety of electrical and fluid connections for the new pump module could occur two or three days after the first spacewalk.

Wheelock, who will be designated as EV1, or extravehicular crew member 1, wearing the spacesuit bearing the red stripes, will be making the fourth spacewalk of his career, while Caldwell Dyson, designated as EV2, wearing the unmarked spacesuit, will be making her first spacewalk.