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SpaceFlight:
Space Shuttle's Return to Flight |
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125 van 126 |
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| Geplaatst door: KJ van Til op 22-04-05 00:49 |
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Mission: International Space Station Flight LF1 (STS-114) Shuttle: Discovery Launch Pad: 39B Planning window: No earlier than May 22 to June 3, 2005 Duration: 12 days Orbital Insertion Altitude: 122 nautical miles Orbit Inclination: 51.60° Countdown begins: T-43 hours Note: Live countdown coverage will be activated approximately six hours prior to liftoff. Aan de shuttle zijn enkele veranderingen aangebracht: o.a. zijn de steunen waarmee de Externe Brandstoftank aan de Shuttle vastzit voorzien van verwarmings elementen. Hierdoor heeft ijsvorming geen kans. Voorheen werd dit voorkomen door isolatielagen (schuim) aan te brengen op de steunen. Echter vertoonden deze de neiging tot afbreken en konden zodoende schade veroorzaken. Verder kan op het uiteinde van de robotarm een extra verlenging gemonteerd worden zodat de bemanning, in een baan om de aarde, de hittewerende laag kan controleren met een camera en een laser welke op de verlengde arm gemonteerd zijn. Zodoende is eventuele reparatie voor terugkeer mogelijk. Twee van de zeven astronauten, Steve Robinson and Soichi Noguchi, zullen tijdens deze vlucht drie ruimtewandelingen uitvoeren om reparatiewerkzaamheden te trainen.Nog meer feiten hierover? |
| Brrrrr,.... wat heet,... | Reactie van: KJvTil op 22-04-05 01:15 |
| De temperatuur van de vloeibare waterstof, de twee na koudste vloeistof ter wereld, in de externe brandstoftank van de Space Shuttle, bedraagt -253 graden celsius. Op het moment van verbranding samen met de vloeibare zuurstof is de temperatuur in de verbrandingskamer +3315 graden Celsius. Dit is heter dan het kookpunt van ijzer,... |
| Space Shuttle Main Engine | Reactie van: KJvTil op 22-04-05 01:20 |
| Elke Space Shuttle Main Engine (SSME) wordt gecontroleerd door een eigen computer. Dit gebeurt 50 keer per seconde gedurende de aftel procedure en de aangedreven vlucht. Als er onregelmatigheden worden geconstateerd, dan kan de controlerende computer de motor uitschakelen. |
| Update: Return to Flight | Reactie van: KJvTil op 30-04-05 01:38 |
| Return to Flight Moves to July Window. NASA announced today that 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. "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." "We'll be ready to fly when the Space Shuttle is ready," said Mission Commander Eileen Collins. "As a crew, we have great confidence in the high level of technical capability addressing these issues in the Shuttle program and across NASA. We've known all along that there might be some delays as we return to flight, and it may take a little longer to get it right. |
| Update-2: RtoF | Reactie van: KJvTil op 30-04-05 01:49 |
| The primary problem facing shuttle program managers is the potential threat of ice debris shaking off the external fuel tank during launch and causing impact damage to the shuttle's fragile heat-shield tiles or wing leading edge panels. The foam responsible for Columbia's demise was intended to prevent ice from building up around the fittings that attach struts holding the nose of the shuttle to the tank. The so-called bipod foam has been eliminated in favor of small heaters. Foam application techniques were changed to minimize the chances for foam shedding in general. Engineers believe the largest piece of foam that can come off the tank today is less than a half ounce. The piece that hit Columbia weighed some 1.67 pounds. But recent testing shows ice buildups in two areas of the tank still pose a threat. One of those areas is where an oxygen feedline bellows is located. The bellows allows the propellant line to respond to the effects of supercold liquid oxygen and to flex slightly during launch. The testing shows ice can build up on the bellows or on a bracket holding the line in place. Another ice problem area is near the tip of the tank around brackets that hold a pressurization line in place. During a detailed review of past launches, engineers were able to identify signs of past ice damage on the belly of the shuttle. The review showed a clear bias for damage on the right side of the belly, which is consistent with ice falling from the feedline bellows area. Recent testing shows the impact energy of ice debris does not depend on whether it is rock solid or somewhat slushy. The question is, when does the ice break off? And how does the airflow between the shuttle and the external tank affect the trajectory of any such debris? Ice and foam behave very differently when they enter the airstream around a space shuttle. That airflow tends to stop a piece of lightweight foam in its tracks, which increases the relative velocity of an impact as the shuttle, in effect, runs into the debris at high speed. Ice does not decelerate as rapidly, which lowers the relative impact velocity and results in a very different transport mechanism. "This is a very complex problem," said shuttle program manager Bill Parsons. "Ice can come off early in the flight and it doesn't have a transport mechanism to ever get to the vehicle. There's a small region in there when you're at a particular Mach number that you have a transport mechanism that gets this ice to the vehicle. That's what we've learned. "We've learned that through a lot of research and through previous damage the vehicle received. We've had hits on (solid rocket booster) cork that we attribute to the LOX (liquid oxygen) feedline bellows ice, we've had some hits in the tile that we attribute at this point in time to the LOX feedline bellows ice. "That was the information that said, hey wait a minute, maybe we've been a little lucky (in past flights), maybe we don't understand this problem as well as we should and therefore we need to go and understand this problem and understand if we've been lucky or the design of this vehicle, and the way this ice comes off, won't transport it towards the vehicle." While testing showed a low probability of ice damage, there is "still a probability that pieces of ice can come off and hit the vehicle and cause damage," Parsons said. "Because of that, it became important to eliminate that." NASA plans to install a heater on both of the external tanks currently at the Kennedy Space Center, including Discovery's, to eliminate the problem once and for all. After an already scheduled practice countdown next week with Discovery's crew, the shuttle eventually will be rolled back to the Vehicle Assembly Building where engineers will attach a feedline bellows heater. The shuttle then will be hauled back out to launch complex 39B for work to ready the ship for takeoff July 13. Engineers believe they have about 20 days of contingency time in the current schedule to handle unexpected problems. Managers might even opt to move Discovery to a tank and boosters being prepared for the second post-Columbia mission, although as of this writing, most insiders believe that's a remote possibility. Engineers also plan to either clean or replace 18 insulation blanks on Discovery's rear orbital maneuvering system rocket pods that were contaminated with hydraulic fluid during earlier pad processing. Engineers were initially concerned that normal ascent heating could cause the residual fluid to ignite, but Parsons said additional testing has shown the contamination is not as extensive as initially believed and that cleaning alone may be sufficient. Either way, the work can be done in parallel with other processing. Of more concern to the launch team are two problems that cropped up April 14 during a key test in which the external tank was loaded with a half-million gallons of supercold liquid oxygen and hydrogen. Two of four sensors in the hydrogen portion of the tank operated intermittently. The sensors detect low fuel levels when the shuttle's engines must be commanded to shut down. Running an engine out of hydrogen, resulting in an oxygen-rich shutdown, could be catastrophic and all four fuel depletion sensors must be operational for a countdown to proceed. Engineers believe the sensors are not to blame but so far, they have been unable to find a wiring problem or any other explanation for their behavior during the tanking test. Another vexing problem is the performance of a hydrogen pressurization relief valve. The regulator operates periodically when the tank is loaded to bleed off pressure that builds up as liquid hydrogen turns into a gas. During the tanking test, the valve operated, or cycled, much more than normal and engineers are not yet sure why. Wayne Hale, deputy manager of the shuttle program, said he does not believe the new heater used to keep ice from forming on the forward attachment struts caused the problem, but engineers have not yet ruled out the possibility. "I personally think that's low priority but ... every day intuition can mislead you," he said. "We've got to be rigorous and make sure that's not the problem. It's a little bit of a puzzle to us and we're going to have to do some troubleshooting. "It is possible one of the changes we made to the tank contributed to this situation. There were other things that were done to the tank that had nothing to do with the Columbia accident. ... We're in the process of playing all those things out and we'll work through all of them." Parsons said engineers are well aware of the "law of unintended consequences" and that as you make changes to this vehicle you better be very careful to understand what those changes do to the performance of this vehicle." "One of the things we will be looking very closely at is when we put this LOX feedline bellows heater in that we do no harm. That's the first rule, do no harm." As for why engineers just now realized ice formation around the feedline bellows posed a serious threat, Hale said "we concentrated on the foam because that was the cause of the (Columbia) accident." "But we knew we had to do an exhaustive search through everything that could be a potential problem," he said. "After a great deal of testing and analysis, we've been able to take some 175 potential debris sources off our worry list. We believe we've mitigated those. And we have the engineering evidence to prove they're not a concern. "We knew we had three or four more items to work on and we also knew there was this ice that forms in certain places on the external tank, which we thought was probably not a major concern but we needed to ensure that. So what you've seen here is the diligence and rigor of going through every piece of the process to ensure that we've eliminated at least to the best of our ability the hazard from ascent debris. "We've come to the conclusion we really need to do something about this ice. We have several options to deal with it and it's going to take us just a few more weeks to deal with that problem. We certainly cannot fly until we've convinced ourselves that it's safe to fly." The threat of ice forming around the liquid oxygen feedline bellows prompted NASA to modify the tank in the wake of Columbia to minimize its formation. Engineers thought that would be sufficient and indeed, they believe the so-called "drip lip" modification eliminates 70 percent of the ice that otherwise might form in that area." But the recent testing suggests that is not enough. "This is a 17-inch-diameter pipe that's got a small area that is exposed, cryogenic temperatures are exposed to the outside air and water can condense and form ice inside that cavity," Hale said. "In some of that testing, we liberated pieces as large as 5 inches long ... by probably a couple of inches of ice. That's a pretty sizeable piece of ice." He said engineers plan to release ice in a wind tunnel capable of velocities three times the speed of sound "and see if ice will hold together" in a bid to better understand the threat. "So there's testing going on," Hale said. "But clearly a piece of ice that big, going three times the speed of sound, can do some serious damage. So we need to go understand a little bit about the dynamics. But the bottom line is, if we can eliminate it that would be the best." The proposed heater modification should do just that, assuming, of course, it doesn't cause any "unintended consequences." Other options include the use of infrared spotlights near the pad to warm the outer surface of the tank just enough to preclude ice formation. |
| Update-3: RtoF | Reactie van: KJvTil op 09-06-05 01:13 |
| Discovery, keeping launch of the first post-Columbia mission on target for July 13. The launch window extends to July 31 and as of this writing, engineers have five days of contingency time in the launch processing schedule to handle unexpected problems between now and the opening of the window.
* Assuming no show stoppers emerge during the meetings later this month, commander Eileen Collins and her crew will fly to Kennedy July 9 for the start of the countdown to blastoff of the 114th shuttle mission. Liftoff July 13 is targeted for 3:51 p.m. EDT (1951 GMT). * NASA had hoped to launch Discovery in May, but problems cropped up during a fueling test April 14 that contributed to a decision to delay the flight to mid July. During that test, two of four liquid hydrogen fuel depletion sensors (also known as engine cutoff sensors) failed to operate properly and a pressure relief valve that helps maintain hydrogen tank pressurization in the final two minutes of the countdown cycled more often than usual. * At the same time, the ongoing ice debris verification review raised questions about potentially dangerous buildups of ice around a liquid oxygen feedline bellows assembly that could shake off during launch and damage the shuttle's fragile heat shield tiles or wing leading edge panels. * NASA managers ultimately decided to delay launch and to move Discovery to a different set of boosters and a modified external tank equipped with a heater on the feedline bellows to prevent ice formation. Engineers are still debating the threat posed by ice around brackets at the top of the tank. * The new tank also features an older-style single-screen diffuser, which injects a jet of helium gas into the hydrogen tank to help keep the supercold fuel circulating at the proper temperature. It also provides the pressurization needed after the tank is isolated from ground systems one minute 52 seconds prior to launch. * Engineers believe the unusual valve cycling during the April 14 tanking test was due to a newer style dual-screen diffuser. During the April 14 test and a second tanking test May 20, the valve cycled 13 times. Based on past experience, it was expected to cycle eight or nine times. * By switching back to the older single-screen diffuser, engineers are confident the problem will not recur during the launch countdown. But testing continues to make sure. * As for the engine cutoff sensors, NASA managers now believe the intermittent operation in April most likely was do to a wiring issue that was resolved during troubleshooting. The sensors worked properly during the May 20 tanking test and engineers believe the sensors in Discovery's new tank will behave normally as well. (Bron: spaceflight now) |
| Update-4: RtoF | Reactie van: KJvT op 29-06-05 13:09 |
| Orbiter: Discovery Mission: STS-114 Launch: July 13, 2005 @ 3:51 p.m. EDT (1951 GMT) Site: Pad 39B, Kennedy Space Center, Florida Landing: July 25 @ 11:01 a.m. EDT (1601 GMT) Site: Shuttle Landing Facility, KSC |
| Final Authorization | Reactie van: KJvTil op 05-07-05 18:30 |
| Discover Awaits Final Authorization For Launch. Cape Canaveral FL (SPX) Jul 04, 2005 The Space Shuttle Program recently concluded a two-day Flight Readiness Review (for Discovery) by announcing a launch date of July 13, 2005. The next major review of launch readiness is two days before launch, when the Mission Management Team meets to give the final authorization for launch. At Launch Pad 39B, final preparations for launch are under way. Loading of hypergolic propellants should be completed this weekend. This process includes loading the propellants monomethyl hydrazine and nitrogen tetroxide into the Orbiter Maneuvering System and Forward Reaction Control System. The flight crew visited the pad yesterday to perform an inspection for sharp edges in the Orbiter. After the crew inspection was completed, a payload contamination walk down was performed, closeout photos were taken and the payload bay doors closed for flight. All four Extravehicular Mobility Units (EMU) have been installed in the Orbiter. The crew will wear the EMU suits during the three spacewalks scheduled during the mission. |
| Update-5: RtoF | Reactie van: KJvTil op 11-07-05 20:10 |
| SUNDAY, JULY 10, 2005 2200 GMT (6:00 p.m. EDT) ---------------------- COUNTDOWN BEGINS! The first space shuttle launch countdown since Columbia has just commenced at Kennedy Space Center for Wednesday's liftoff of Discovery. The launch team is performing the countdown from the Complex 39 Launch Control Center's Firing Room 3. Controllers were called to their stations 30 minutes ago in preparation for beginning the count. ---------------------- Clocks stand at T-minus 43 hours and counting. About 27 hours of built-in holds are planned over the next three days leading to liftoff at 3:51 p.m. EDT (1951 GMT) Wednesday from pad 39B. ---------------------- NASA hopes to resume shuttle flights Wednesday, weather permitting, with a three-spacewalk mission to repair the international space station's stabilization system, to deliver critical supplies and equipment and to prove the design defects that led to the Columbia disaster have been corrected. ---------------------- The shuttle Discovery's countdown ticked smoothly through its initial stages today as engineers geared up to load liquid hydrogen and oxygen to power the ship's electricity generating fuel cells. Forecasters, meanwhile, continue to predict a 70 percent chance off acceptable weather at launch time Wednesday. |
| Update-5: RtoF | Reactie van: KJvTil op 13-07-05 10:39 |
| Did you know? If the countdown clock reads T-26 hours and counting, that doesn't mean the Shuttle will launch in 26 hours. During every Shuttle countdown, there are several times when the clock is temporarily stopped. These periods are called "built-in holds," and they vary in length from as little as 9 minutes to as long as several hours. For this reason, hold times must be taken into consideration when watching the countdown clock. The Shuttle team uses built-in holds to synchronize with other countdown clocks, monitor weather events, make final adjustments to the launch time, and check all systems before proceeding. |
| Lanceertijdstip | Reactie van: KJvTil op 13-07-05 11:04 |
| Als ik het goed heb (blijft altijd lastig met al die verschillende klokken en GMT, EDT enz...) dan wordt de Shuttle Discovery vanavond van Launch Pad 39B gelanceerd rond 21.50, tenminste als er geen vertragingen meer zijn. De 13e is wel weer een lekkere datum,... Apollo 13,... Die Amerikanen zijn toch al zo bijgelovig,... KJ |
| Shuttle Damaged... | Reactie van: KJvTil op 13-07-05 13:39 |
| Shuttle Damaged Ahead Of Planned Liftoff. Cape Canaveral (AFP) Jul 12 - A plastic and foam cover fell off a window of Discovery Tuesday, causing some damage to the space shuttle on the eve of its planned launch, NASA said, indicating it hoped to fix the problem swiftly. The protective cover, which is taken off before the launch, fell about 20 meters (60 feet) onto one of the shuttle's two orbital maneuvering systems, which are used once the craft is in orbit. Some of the tiles on the edge of the system were damaged in the incident, said Stephanie Stilson, NASA's manager for Discovery preparations. "I have been assured it can be fixed quickly and then we can move on," she said. "There is plenty of time to work out an issue like this," she said. |
| Update-6: RtoF | Reactie van: KJvTil op 15-07-05 13:09 |
| De lancering welke afgelopen woensdag plaats had moeten vinden werd afgelast. Dit vanwege een defecte sensor in de externe brandstoftank. Er zijn daar vier sensoren aanwezig (onderin de tank) die alle vier moeten werken. Eén ervan werkte niet. Er werd onderbroken data gezonden door de sensor, terwijl dit een constante stroom van gegevens zou moeten zijn. De sensoren moeten de motoren uitschakelen wanneer de brandstof tank een bijna leeg niveau heeft bereikt. Dit om de motoren tegen beschadiging te beschermen. Het protocol schrijft voor dat als alle vier sensoren niet naar behoren werken, de lancering wordt afgebroken. |
| July 26 Launch Target | Reactie van: KJvTil op 22-07-05 13:17 |
| July 26 Targeted for Discovery Launch. NASA is wrapping up work on Discovery's fuel sensor circuit problem and now plans to pick up the countdown Saturday, with a launch no earlier than 10:39 a.m. EDT (14.39 GMT) on Tuesday, July 26. Het probleem wat zich voordeed afgelopen week heeft men niet op kunnen sporen en kunnen repareren. Het blijft dus nogal vaag wat er nu precies aan de hand was/is. Wel heeft men een aantal mogelijke problemen/veroorzakers weggewerkt. In the meantime, technicians will work with grounding wiring associated with the liquid hydrogen engine cutoff sensor system, as well as adjust the configuration of components within Discovery's point sensor box. During a briefing held after a mission managers meeting, NASA Space Shuttle Program Manager Bill Parsons said "We've all agreed that this work is doable, and that it all takes us to a launch on the 26th" (+ View Press Release). The engine cutoff sensors are mounted at the bottom of the External Tank and trigger the orbiter's engines to shutdown in the event liquid hydrogen levels run expectedly low. The system failed a routine pre-launch check during the countdown on July 13, causing NASA to postpone Discovery's first launch attempt. |
| Update-7: RtoF | Reactie van: KJvTil op 25-07-05 13:50 |
| NASA managers today cleared the shuttle Discovery for another launch try Tuesday, weather permitting, on a critical flight to service and resupply the international space station. The decision came after senior managers agreed on a strategy that would permit blastoff even if - and only if - the shuttle experiences a fuel sensor problem like the one that grounded the ship July 13.
Despite exhaustive, around-the-clock tests, engineers were never able to find the problem that caused hydrogen main engine cutoff - ECO - sensor No. 2 to "fail wet" during the July 13 launch attempt. The ECO sensors are part of a backup system that ensures the shuttle's main engines shut down normally before the tank runs out of fuel. NASA launch rules require all four ECO sensors to be operating before a countdown can proceed. But in a routine pre-launch test during Discovery's first launch try, ECO sensor No. 2 continued indicating it was wet after computer commands were sent to simulate a dry tank. They initially were hopeful that electrical interference caused by subtle grounding problems might explain why sensor No. 2 failed to respond properly. The grounding problems were fixed, but troubleshooters were never able to duplicate the unexpected sensor behavior. Even so, they believe the testing completed to date proves the problem, whatever the cause, is not a generic defect and as such, they are confident it will not affect the other sensors. "We have literally run every check that we can think of that people could suggest to us to try to find this problem and so far, no repeat," said Hale. "So we have developed a plan that says we have to go to cryogenic temperature to find out what's going on next. "We also need to turn on all the equipment in the orbiter and the launch pad area to see if there's any electromagnetic interference that we could not check piece wise earlier. So both of those things together say we are ready to go the launch countdown configuration to see our next level of checking." Engineers plan to begin pumping liquid oxygen and hydrogen rocket fuel into Discovery's external tank around 12:30 a.m. Tuesday. Two minutes after the hydrogen ECO sensors are submerged in super-cold hydrogen, engineers will begin sending commands to simulate a dry tank to make sure none of the sensors have "failed wet." Then, just before the crew straps in around 7:19 a.m., the commanding will stop and the main countdown computer will carry out a series of checks to verify the sensors change state, from wet to dry and back again, on command. A final check is planned about a half-hour before liftoff. "We are going to continuously check the validity of the signal from the sensor all the way to the orbiter computers during the tanking (process) so if at any time any one of these circuits fails, we will know about it, we'll be able to isolate time-wise when it happened, we'll be able to know what was going on in the ship, either electrically or thermally, so that will give us a clue to where the problem might lie," Hale explained. To help isolate the problem during fuel loading, engineers swapped the wiring between ECO sensors 2 and 4. If a problem shows up during fueling with sensor No. 4, engineers will have high confidence the problem is in the sensor itself or somewhere in the wiring between the sensor and the point sensor box. If sensor No. 2 misbehaves, they will have high confidence the problem is in the point sensor box. Because electrical interference could still be a contributing factor, engineers will conduct checks during the final hours of the countdown to isolate any such signatures. Here's the ECO sensor launch strategy at a glance: -Any ECO sensors "fail dry:" Scrub -More than one hydrogen ECO sensor malfunctions: Scrub -Any liquid oxygen ECO sensors fail: Scrub -Hydrogen ECO sensors 1 or 3 malfunction: Scrub -All four hydrogen ECO sensors work normally: Launch -Hydrogen ECO sensor 2 fails wet: Launch -Hydrogen ECO sensor 4 fails wet: Launch Because of the wiring swap, "if the problem recurs, it will give us an indication of whether the problem is in our famous point sensor black box or in the wiring or the sensor itself," Hale said. "So we'll know that. And we've defined a very rigid set of requirements and tests to be done if this problem re occurs. We also know that we've done a lot of moving around in the aft, we've mated and demated connectors, we've wiggled a lot of wiring, we've tested the point sensor box extensively and it is possible that we have caused whatever the problem was to go away. "So if the problem doesn't recur, we feel we have good redundancy to go fly and that's why we are prepared, following the tests to ensure all these sensors are working right ... to load the crew up and go fly." But if sensors 2 or 4 act up, "then we're going to do some more tests just to make sure we understand what's causing that to happen," Hale said. "And if we're comfortable that we have a good understanding of the cause, then we can go fly for those specific two cases. If anything else happens - if we have any of the liquid oxygen sensors fail, if we have a hydrogen sensor that fails to a dry state instead of the wet state, if we have a sensor that fails on channel 1 or 3 or multiple sensor failures, anything like that happens - we're going to stop because that says we really need to do more testing." But launching with three operational sensors would violate NASA's launch commit criterion requiring all four to be working at launch. The agency's original launch rule required three operational ECO sensors for a countdown to proceed. But in the wake of the 1986 Challenger disaster, the LCC was amended to four-of-four because of concerns two sensors could be knocked out by a single failure in an upstream electronic black box known as a multiplexer-demultiplexer. The single-point failure was corrected during Discovery's last overhaul, but the four-of-four launch rule remained on the books. And that rule will be in place Tuesday. But the mission management team is prepared to sign an exception to the rule - permitting Discovery to launch with three of four ECO sensors - depending on what happens after the tank is loaded with fuel. |
| Lancering geslaagd! | Reactie van: KJvTil op 26-07-05 23:20 |
| De shuttle is met succes gelanceerd! De verslaglegging van de NOS was echter zeer gebrekkig vond ik. De betreffende journalisten hadden, mijn inziens, niet echt vakkennis en noemden de brandstof bijvoorbeeld 'benzine',... Zakt je broek wel een beetje vanaf. Of je snapt het zelf niet,... òf je vindt de gemiddelde Nederlander zo achterlijk dat je maar de term 'benzine' gebruikt,... Daarnaast zat volgens de journalist de 'falende' sensor (waardoor vorige week de start werd afgeblazen) in de boosters. Hmmm,... die zat dus onderin de 'main fuel tank'. Waarschijnlijk weet hij ook niet het verschil tussen vaste en vloeibare brandstof,... zucht,... In ieder geval: lancering geslaagd! Nu ook nog heel terug,...maar dat weten we over 12 dagen. KJ :-) |
| Update-8: RtoF | Reactie van: KJvTil op 27-07-05 12:03 |
| The crew of Space Shuttle Discovery was awakened this morning at 12:39 a.m EDT to start its first full day in space. As the orbiter spends the day chasing the International Space Station, the crew will use Discovery's robot arm to inspect the vehicle's exterior.
Unprecedented imagery captured during Tuesday’s ascent to orbit enabled engineers to see two so-called "debris events." A camera mounted on the external tank caught what appeared to be a small fragment of tile coming from Discovery's underside on or near the nose gear doors. A later image about the time of Solid Rocket Booster separation showed an unidentified piece departing from the tank and exiting away, apparently not striking the orbiter. The crew was notified of these observations and told that imaging experts would be analyzing the pictures. Mission managers will review the information gathered yesterday and today to help determine the health of Discovery's thermal protection system over the next four days before it is cleared for landing later in the flight. |
| Update-9: RtoF setback! | Reactie van: KJvTil op 28-07-05 09:53 |
| In a major setback for NASA, senior managers today grounded the shuttle fleet, saying no more missions will be launched until engineers figure out why large, potentially catastrophic pieces of foam insulation broke away from the shuttle Discovery's external fuel tank during launch Tuesday.
"Until we're ready, we won't go fly again," said shuttle program manager Bill Parsons. "I don't know when that might be, I'll state that up front. We're just in the beginning of this process of understanding. This is a test flight. This is a flight we had to go off and try to get as much information as we could and see if the changes that we had made to the tank (in the wake of the Columbia disaster) were sufficient. Obviously, we have some more work to do.
The largest pieces of foam did not strike Discovery and engineers believe the ship's seven-member crew will be able to safely return to Earth Aug. 7 after a long-awaited mission to deliver supplies and equipment to the space station. But the foam problem took the luster off an otherwise successful mission, and for good reason. Deputy shuttle program manager Wayne Hale said if the largest piece of debris had fallen off earlier, while Discovery was still in the lower reaches of the atmosphere, "we think this would have been really bad. So it's not acceptable, OK?" NASA's top priority in the wake of the accident - and the No. 1 recommendation of the Columbia Accident Investigation Board - was to redesign the way the foam is applied to the tank to minimize so-called foam shedding. Engineers were confident Discovery's tank would shed nothing larger than a marshmallow, repeatedly stating their belief that the new tanks were the safest ever built. But during Discovery's climb to space, a few seconds after the ship's solid-fuel boosters separated two minutes and five seconds into flight, a relatively large, pillow-size piece of foam ripped away from an aerodynamic ramp intended to prevent turbulent airflow around cable trays and pressurization lines. A new camera mounted on the external tank to monitor the tank's performance showed the debris lifting off and quickly tumbling away in the thin, supersonic airflow. Earlier, part of a heat shield tile near the nose landing gear door cracked off and fell away. That incident is still under study, but it appears relatively minor. The tank debris passed under the shuttle's right wing and did not appear to come close to actually striking the orbiter. But the size of the yard-long piece of debris was a shock. In addition, camera footage shot by Discovery's crew after the tank was jettisoned showed two other relatively large divots in the foam near the area where two struts held the shuttle's nose to the tank. "We saw a couple of divots in areas that frankly are not satisfactory to us," Hale said. "We spent a lot of time working on what we call the liquid hydrogen interface ring, the LH2 interface, to make sure we would not loose pieces of foam and in fact, we see about a six- or seven-inch piece of foam that came off right there at that interface, which is unsatisfactory and we've got to work on that." |
| Update-10: RtoF | Reactie van: KJvTil op 28-07-05 13:30 |
| Discovery heeft, om 13.18uur(GMT), een geslaagde docking uitgevoerd met het ruimtestation! Bij de docking worden de 100 ton wegende Discovery en het 200 ton wegende ruimtestation aan elkaar gekoppeld. De docking werd uitgevoerd door Commander Eileen Collins. De eerste docking is een soort van flexibele verbinding met het ruimtestation. Door middel van veren en dempers worden trillingen tussen de twee verschillende voertuigen uitgedempt, waarna klemmen een vaste verbinding tot stand brengen. Daarna volgt een anderhalf uur durende lekkage check aan beide kanten van de korte verbindingstunnel, waarna uiteindelijk de verbindingsluiken geopend kunnen worden. |
| Update-11: RtoF | Reactie van: KJvTil op 29-07-05 12:10 |
| STS-114 crewmembers used the International Space Station's robot arm this morning to lift the Raffaello Multi-Purpose Logistics Module out of Space Shuttle Discovery's payload bay and attach it to the Station. Raffaello, a pressurized cargo carrier, contains 15 tons equipment and supplies for the Station. Shuttle and Station crewmembers will enter Raffaello for the fist time later today. |
| Update-12: RtoF | Reactie van: KJvTil op 04-08-05 22:44 |
| Astronauten hebben een unieke nog nooit eerder voorgekomen ruimtewandeling uitgevoerd. Hierij zijn enkele uitstekende stukjes voegmateriaal tussen de hittewerende tegels uitgehaald. Deze stukjes voegmateriaal zijn aangebracht om te voorkomen dat de tegels door onderlinge frictie, veroorzaakt door trillingen en uitzetten en krimpen van het chassis, beschadigd raken. De uitstekende delen zouden voor extra turbulentie en daardoor een sterk verhoogde temperatuur kunnen zorgen tijdens de afdaling in de aardse atmosfeer. Een andere mogelijke ruimtewandeling, om een stuk loszittende isolatiedeken bij één van de cockpitramen weg te halen, gaat niet plaats vinden, zo deelde NASA mee. Het zou geen gevaar opleveren bij de afdaling. |
| Update-13: RtoF | Reactie van: KJvTil op 05-08-05 10:51 |
| The STS-114 crew will return the Raffaello Multi-Purpose Logistics Module to Space Shuttle Discovery's payload bay later this morning. The hatches between Raffaello and the International Space Station were closed at 1:42 EDT this morning. Raffaello is filled with unneeded items from the Station. The Station’s robotic arm is slated to be used to undock Raffaello from the Station at 6:24 EDT and place in the payload bay at 7:34 EDT. In other activities, the STS-114 and Expedition 11 crews are preparing for Discovery’s departure. The Shuttle is scheduled to undock from the Station at 3:24 a.m. EDT Saturday and land at Kennedy Space Center, Fla., Monday morning. |
| Update-14: RtoF | Reactie van: KJvTil op 09-08-05 12:49 |
| Er is zojuist een 'Go' gegeven aan Commander Eileen Collins voor de 'De-orbit Burn', zodat de shuttle de omloopbaan zal verlaten en de landing in zal zetten. De 3 minuten durende 'De-orbit Burn' zal over ongeveer 20 minuten aanvangen. |
| Update-15: RtoF | Reactie van: KJvTil op 10-08-05 15:09 |
| De Discovery is dinsdag zonder problemen perfect geland in de vroege ochtend in Californië. Het weer op de thuisbasis in Florida liet te wensen over, waarna naar Californië werd uitgeweken. Hiermee komt een einde aan deze veelbesproken Shuttle vlucht. |
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