Category: Space Shuttle

Space Shuttle Discovery on the launch pad. Image credit: NASA. Click to enlarge
NASA announced the earliest the Return to Flight Space Shuttle mission (STS-114) could launch is 2:14 p.m. EDT, Sunday, July 17. Mission Management Team and engineering meetings took place last night and today at NASA’s Kennedy Space Center.

Team members reviewed data and possible troubleshooting plans for the liquid hydrogen tank low-level fuel cut-off sensor. The sensor failed a routine pre-launch check during the launch countdown Wednesday, causing mission managers to scrub Discovery’s first launch attempt.

The sensor protects the Shuttle’s main engines by triggering shutdown if fuel runs unexpectedly low. The sensor is one of four inside the liquid hydrogen section of the External Tank (ET).

A new official launch date will be scheduled once a troubleshooting plan is complete and engineers are working on a solution. Space Shuttle Program managers plan meetings tomorrow to discuss the problem and finalize the troubleshooting plan.

The launch control team began troubleshooting while the liquid oxygen and liquid hydrogen was drained from the ET last night. The No. 2 liquid hydrogen sensor in the ET’s liquid hydrogen tank continued to read ‘wet’ and did not transition to a ‘dry’ indication once the tank was completely drained.

Following de-tanking operations, the same commands that were sent during the launch countdown were repeated while draining. While going through commands, sensor No. 2 continued to show ‘wet’ instead of ‘dry.’ The firing room reissued commands, and the sensor went to ‘dry’ as it should. Another round of commands was sent and sensor No. 2 performed as expected, with all sensors in the ‘dry’ state. Space Shuttle Discovery remains at Launch Pad 39B. The Rotating Service Structure was put back around the vehicle last night.

The STS-114 crew, led by Commander Eileen Collins, remains at Kennedy Space Center while engineers assess the problem. During their 12-day Return to Flight mission to the International Space Station, Discovery’s seven crew members will test new techniques and equipment designed to make Space Shuttle missions safer. They’ll also deliver supplies and make repairs to the Space Station.

For the latest information about the STS-114 mission, visit: http://www.nasa.gov/returntoflight

Original Source: NASA News Release

The Space Shuttle sits on the Mobile Launcher Platform (MLP). Image credit: NASA/KSC. Click to enlarge
The launch of NASA’s Space Shuttle Return to Flight mission, STS-114, will take place no earlier than Saturday, July 16 at 2:40 p.m. EDT. Space Shuttle Discovery’s liftoff today from NASA’s Kennedy Space Center, Fla., was postponed at 1:30 p.m. EDT.

During countdown activities, a low-level fuel cut-off sensor located inside the External Tank failed a routine prelaunch check. The sensor protects a Shuttle’s main engines by triggering their shut down in the event fuel runs unexpectedly low. The sensor is one of four inside the liquid hydrogen section of the External Tank.

The External Tank’s liquid oxygen and liquid hydrogen were drained this evening. While the tank was being emptied, engineers monitored and collected data on the liquid hydrogen sensor that failed. They will continue to collect and analyze data overnight.

Space Shuttle Program managers plan a series of meetings tomorrow to discuss the problem and determine the steps necessary to get back into the launch countdown.

The STS-114 crew will remain at Kennedy Space Center for now while engineers work on the problem.

During their 12-day Return to Flight mission to the International Space Station, Discovery’s seven crew members will test new techniques and equipment designed to make Space Shuttles safer. They’ll also deliver supplies and make repairs to the Space Station.

For the latest information about the STS-114 mission, visit:
http://www.nasa.gov/returntoflight

Original Source: NASA News Release

Space shuttle Discovery on the launch pad. Image credit: NASA. Click to enlarge.
A new study, funded in part by the Naval Research Laboratory and the National Aeronautics and Space Administration (NASA) reports that exhaust from the space shuttle can create high-altitude clouds over Antarctica mere days following launch, providing valuable insight to global transport processes in the lower thermosphere[mhs1]. The same study also finds that the shuttle’s main engine exhaust plume carries small quantities of iron that can be observed from the ground, half a world away.

The international team of authors of the study, to appear in the July 6 issue of Geophysical Research Letters, used the STS-107 Shuttle mission as a case study to show that exhaust released in the lower thermosphere, near 110 kilometers altitude, can form Antarctic polar mesospheric clouds (PMCs). The thermosphere is the highest layer in our atmosphere, with the mesosphere (between 50-90 kilometers above the Earth), stratosphere, and troposphere below.

New observations presented by the research team from the Global Ultraviolet Imager (GUVI) on NASA’s Thermosphere, Ionosphere, Mesosphere, Energetics and Dynamics (TIMED) satellite reveal transport of the STS-107 exhaust into the southern hemisphere just two days after the January 2003 launch. Water from the exhaust ultimately led to a significant burst of PMCs during the 2002-2003 southern polar summer, observed by the Solar Backscatter Ultraviolet (SBUV) satellite experiment. The inter-hemispheric transport followed by Antarctic PMC formation were unexpected.

PMCs, also known as noctilucent clouds, appear near 83 kilometers altitude and are made up of water ice particles created through microphysical processes of nucleation, condensation, and sedimentation. They typically appear in the frigid polar summer mesosphere where temperatures plummet below 130? Kelvin (-220? F). Little is known about the specific processes that lead to PMC formation.

According to the study’s lead author, Dr. Michael Stevens, a research physicist at the E.O. Hulburt Center for Space Research at the Naval Research Laboratory, the research produced multiple groundbreaking science results.

“This research is exciting in that it extends a new explanation for the formation of these clouds by demonstrating the global effect of a Shuttle exhaust plume in a region of the atmosphere that has traditionally not been well understood,” said Stevens.

Some believe that the impact of anthropogenic change in the lower atmosphere is reflected in these upper atmospheric clouds. Although historically PMCs have only been seen in the polar region, in recent years PMCs have been spotted at lower latitudes as far south as [mhs2]Colorado and Utah, renewing interest and sparking debate on the implications. However, the findings of this work, “call into question the interpretation of the impact of late 20th century PMC trends solely in terms of global climate change,” Stevens said. The team concludes that the water from a space shuttle’s exhaust plume can contribute a remarkable 10-20 percent to PMCs observed during one summer season in Antarctica.

A key piece of data that confirmed the plume’s arrival in Antarctica was the ground-based observation of iron atoms near 110 km. The presence of iron at this altitude originally perplexed scientists because there is no known natural source there. The data imply that iron ablated, or vaporized, by the main engines of the Shuttle was transported along with the water plume, arriving in Antarctica three to four days after the January 2003 launch. Both the water plume and the presence of iron demonstrate that the mean southward wind inferred from the team’s data is much faster than gleaned from global circulation models or wind climatologies.

“This tells us something new and exciting about transport in this region of the atmosphere,” said Stevens. “It can be so fast that a shuttle plume can form ice over Antarctica before other loss processes can really take effect. We must take great care in interpreting the long-term implications to observations and features of these clouds because of this contribution from the shuttle and the potential contribution from many other smaller launch vehicles.”

NRL and NASA funded the study, with contributions from the National Science Foundation, the British Antarctic Survey in Cambridge, United Kingdom, and the University of Illinois, Urbana-Champaign. Other researchers on the study include Robert Meier of George Mason University, Fairfax, Va.; Xinzhao Chu of the University of Illinois, Urbana-Champaign; Matthew DeLand of Science Systems & Applications, Inc., Lanham, Md.; and John Plane of the University of East Anglia, Norwich, United Kingdom.

Original Source: NRL News Release

Space shuttle Discovery moving from the Vehicle Assembly building. Image credit: NASA. Click to enlarge.
NASA will begin the countdown for the Return to Flight launch of Space Shuttle Discovery on mission STS-114 July 10 at 6 p.m. EDT, 43 hours before liftoff. Discovery’s seven-member crew will test new equipment and procedures to increase the safety of the Shuttle and deliver spare parts, water and supplies to the International Space Station.

The Kennedy Space Center (KSC) launch team will conduct the countdown from Firing Room 3 of the Launch Control Center. The countdown includes nearly 27 hours of built-in hold time leading to a preferred launch time at about 3:51 p.m. on July 13 with a launch window extending about five minutes.

This historic mission is the 114th Space Shuttle flight and the 17th U.S. flight to the International Space Station. STS-114 is scheduled to last about 12 days with a planned KSC landing at about 11:01 a.m. EDT on July 25.

Discovery rolled into KSC’s Orbiter Processing Facility (OPF) on Aug. 22, 2001, after returning from its last mission STS-105 in August 2001 and undergoing an Orbiter Major Modification period. The Shuttle rolled out of OPF bay 3 and into the Vehicle Assembly Building (VAB) on March 29. While in VAB high bay 1, Discovery was mated to its redesigned External Tank and Solid Rocket Boosters. The entire Space Shuttle stack was transferred to Launch Pad 39B on April 7.

In order to allow for the addition of a new heater to the External Tank, Space Shuttle Discovery was rolled back to the VAB on May 26 for that modification to be performed. Discovery was removed from its External Tank and attached to a new tank originally scheduled to fly with orbiter Atlantis on mission STS-121, the second Return to Flight mission.

Discovery was rolled back out to Launch Pad 39B on June 15 in preparation for the July launch window.

On mission STS-114, the crew will perform inspections on orbit for the first time of all of the Reinforced Carbon-Carbon (RCC) panels on the leading edge of the wings and the Thermal Protection System tiles using the new Canadian-built Orbiter Boom Sensor System and the data from 176 impact and temperature sensors. Mission Specialists will also practice repair techniques on RCC and tile samples during a spacewalk in the payload bay.

In the payload bay, the Multi-Purpose Logistic Module Raffaello, built by the Italian Space Agency, will carry 11 racks with supplies, hardware, equipment and the Human Research Facility-2.

During two additional spacewalks, the crew will install the External Stowage Platform-2, equipped with spare part assemblies, and a replacement Control Moment Gyroscope contained in the Lightweight Multi-Purpose Experiment Support Structure.

The STS-114 crew includes Commander Eileen Collins, Pilot James Kelly, and Mission Specialists Soichi Noguchi, Stephen Robinson, Andrew Thomas, Wendy Lawrence and Charles Camarda.

Original Source:NASA News Release

Space shuttle Discovery back on its launch pad. Image credit: NASA. Click to enlarge.
With new safety modifications, the Space Shuttle Discovery is back at Launch Pad 39B at NASA’s Kennedy Space Center, Fla. Carried by a giant Crawler Transporter, Discovery arrived at the pad at 12:17 p.m. EDT today in preparation for its historic Return to Flight mission (STS-114) planned for July.

“We’ve addressed some additional concerns about ice formation on the external fuel tank,” said NASA’s Deputy Associate Administrator for International Space Station and Space Shuttle Programs Michael Kostelnik. “This is an even safer vehicle for Commander Eileen Collins and her crew, and the new modifications will ensure this important mission to the International Space Station is successful.”

Discovery’s journey took a little longer than expected. It left the Vehicle Assembly Building about 2:00 a.m. EDT for its four-mile journey. The Crawler Transporter, which has a top speed of about one mph, traveled even slower than normal today. It stopped frequently, so engineers could address overheating bearings. But when Discovery finally rolled up to the pad around lunchtime, it was a satisfying sight for those who have been working more than two years to get the Shuttle back to space.

“Seeing Discovery back on the launch pad is a visible testament to the dedication of everyone involved in making sure STS-114 is the safest mission it can be,” said Space Shuttle Program Manager Bill Parsons. “We still have some work to do, but today is indicative that the hardware is getting ready for a launch in July.”

With Discovery at the pad, workers will begin final preparations for launch. They will close out, test, and install the payload, NASA’s Italian-built Multi-Purpose Logistics Module, Raffaello.

They will also load the hypergolic propellants for flight. The process includes adding the propellants, monomethyl hydrazine and nitrogen tetroxide, into the Orbiter Maneuvering System and the Forward Reaction Control System.

Discovery was de-mated from its previous External Tank (ET-120) and attached to a new External Tank (ET-121) on June 7. A new heater was added to ET-121 on the feedline bellows. The heater is designed to minimize potential ice and frost buildup on the bellows, a part of the pipeline that carries liquid oxygen to the Shuttle’s main engines. ET-121 was originally scheduled to fly with Atlantis on the second Return to Flight mission (STS-121).

The new tank was fitted with temperature sensors and accelerometers to gather information about the tank’s performance and measure vibration during flight.

“Returning Discovery to the launch pad is the last major processing milestone prior to launch,” said NASA Launch Director Mike Leinbach. “The launch team is completing the final procedures and documentation, and we are looking forward to beginning the launch countdown three days prior to liftoff.”

NASA plans to launch Discovery during a window from July 13 to 31. A launch date will be set during the Flight Readiness Review scheduled for June 29 and 30.

During their 12-day mission, Discovery’s seven crew members will test new hardware and techniques to improve Space Shuttle safety. They will also deliver supplies to the International Space Station.

Video from the rollout will feed on NASA TV available on the Web and via satellite in the continental U.S. on AMC-6, Transponder 9C, C-Band, at 72 degrees west longitude. The frequency is 3880.0 MHz. Polarization is vertical, and audio is monaural at 6.80 MHz. In Alaska and Hawaii, it’s available on AMC-7, Transponder 18C, C-Band, at 137 degrees west longitude. The frequency is 4060.0 MHz. Polarization is vertical, and audio is monaural at 6.80 MHz.

Original Source: NASA News Release

Discovery rolls back to the Vehicle Assembly Building for an upgrade. Image credit: NASA. Click to enlarge.
The Space Shuttle Discovery is back in the Vehicle Assembly Building (VAB) at NASA’s Kennedy Space Center, Fla. The Shuttle will get a new, modified external fuel tank to ensure a safe Return to Flight mission (STS-114).

Discovery, carried by a Crawler Transporter, entered the VAB at 4:30 p.m. EDT. The 10-hour, 4.2 mile trip from Launch Pad 39B was briefly interrupted due to an over heated bearing on the Transporter. Today’s rollback was the 15th in Space Shuttle Program history.

“Rolling back Discovery was the right thing to do and demonstrates our commitment to a safe Return to Flight,” said Shuttle Program Manager Bill Parsons. “We will continue to focus on the processing milestones and complete the additional analysis we determined was required, so that we continue to move toward a launch during the July window.”

Technicians will de-mate Discovery from its External Tank (ET-120) and Solid Rocket Boosters on May 31. Discovery will be attached to ET-121 on June 7. ET-121 was originally scheduled to fly with the Shuttle Atlantis on the second Return to Flight mission (STS-121).

In the VAB, a new heater will be added to ET-121 on the feedline bellows. It is the part of the pipeline that carries liquid oxygen to the Shuttle’s main engines, to minimize potential ice and frost buildup. The tank also has several safety improvements, including an improved bipod fitting that connects it to the Orbiter.

In addition, NASA’s second redesigned tank has been outfitted with temperature sensors and accelerometers, used to measure vibration. These sensors will gather information about the tank’s performance during flight.

After the heater is added to ET-121 and the Shuttle is attached to its new propulsion elements, Discovery will roll back out to Launch Pad 39B in mid-June. Discovery’s payload, the Italian-built Multi-Purpose Logistics Module Raffaello, will be installed in the payload bay, while the Shuttle is on the pad.

Launch of Discovery for STS-114 is targeted for July 13. The launch window extends to July 31. During its 12-day mission, Discovery’s seven-person crew will test new hardware and techniques to improve Shuttle safety and deliver supplies to the International Space Station.

Video from the rollback will feed on NASA TV, available on the Web and via satellite in the continental U.S. on AMC-6, Transponder 9C, C-Band, at 72 degrees west longitude. The frequency is 3880.0 MHz. Polarization is vertical, and audio is monaural at 6.80 MHz. It’s available in Alaska and Hawaii on AMC-7, Transponder 18C, C-Band, at 137 degrees west longitude. The frequency is 4060.0 MHz. Polarization is vertical, and audio is monaural at 6.80 MHz. For NASA TV information and schedules on the Internet, visit: http://www.nasa.gov/ntv

Photos of the rollback are available on the Web at: http://mediaarchive.ksc.nasa.gov/index.cfm

For the latest information about NASA’s Return to Flight efforts, visit: http://www.nasa.gov/returntoflight

Original Source: NASA News Release

Crew of STS-114, practicing for their upcoming launch. Image credit: NASA. Click to enlarge.
NASA announced today July 13 to 31 is the new launch planning window for the Space Shuttle Discovery mission. The new window gives the agency time to do additional work to ensure a safe Return to Flight for Discovery and its crew.

Today’s announcement follows Space Shuttle Program reviews over the past two weeks. Managers identified the need to do more work to validate engineering analyses of potential debris hazards and to make some additional modifications to the external fuel tank. NASA officials and program managers agreed late Thursday to take the time to complete the work.

“This is consistent with our overall approach to the STS-114 mission, which is that we’re going to return to flight, we’re not going to rush to flight,” NASA Administrator Michael Griffin said at a morning news conference at NASA Headquarters. “Our intent with this effort is to make certain we are as safe as we know how to be before we launch the Space Shuttle and its crew. We want it to be right.”

“From the beginning we?ve been milestone-driven,” said William Readdy, NASA associate administrator for Space Operations. “This time, the milestones on debris and ice analyses, propulsion system troubleshooting and External Tank modifications drove us to retarget for July. We?ve never been reluctant to adjust the dates as information becomes available.”

The Return to Flight mission will take Shuttle Commander Eileen Collins and six crew members to the International Space Station. The mission is the first of two test flights to evaluate new thermal protection system inspection and repair techniques and to deliver supplies and equipment to the Station. A transcript of today’s news conference and follow-on technical briefing from NASA’s Johnson Space Center is available at: www.nasa.gov/returntoflight

Original Source: NASA News Release

Mission controllers have decided to give technicians an extra week to get the Space Shuttle Discovery ready for its return to flight. Originally schedule to lift off on May 15, Discovery is now tentatively set to return to orbit on May 22. One reason for the delay is to give technicians more time to test an extension to the Canadarm which will let astronauts examine the shuttle for damage while in orbit. Its launch window closes on June 3, and doesn’t open up again until mid-July when Atlantis is expected to launch.

NASA’s Space Shuttle Discovery arrived at its launch pad completing the next major milestone for Return to Flight of America’s Space Shuttle program. The Shuttle arrived at its launch pad at 12:30 a.m. This was approximately three hours later than its scheduled arrival.

The slight delay was caused when Shuttle processing team members had to replace a Programmable Logic Controller (PLC) circuit card on the Crawler Transporter during the final leg of its journey. The Crawler Transporter is the vehicle which transports the Space Shuttle and its Mobile Launcher Platform to the launch pad. The PLC is an indicator that relays height measurements to the Crawler’s operators while it’s in motion.

The issue occurred during Discovery’s initial attempt to climb the incline ramp leading to Pad 39B. When observed, technicians decided to stop the rollout and then reverse Discovery back down the incline ramp to level ground to test and then replace the circuit card. Once the new card was in place, the Crawler functioned normally and the rollout was completed. The Space Shuttle remained level and in a safe configuration throughout all movements and during the changeout of the card.

Once in place at the launch pad, the shuttle team continued preparation of Discovery for its scheduled launch set for a window of May 15 to June 3.

Original Source: NASA News Release