NASA targets Sept. 23 for next Artemis 1 launch attempt, but a lot has to go right
NASA needs to fix a hydrogen leak, ace a fueling test and secure a critical safety system waiver to even try to launch this month.
NASA's Artemis 1 moon rocket is seen atop its Pad 39B launch pad on Aug. 29, 2022. The mission could make its third launch try on Sept. 23.(Image credit: NASA/Keegan Barber)
NASA's next attempt to launch its new megarocket on a test flight to the moon could lift off by Sept. 23, but only if the agency fixes a leak and receives a critical waiver from the U.S. Space Force.
Jim Free, NASA's associate administrator for exploration systems development, said today (Sept. 8) that NASA's Artemis 1 moon mission launch — the debut of its giant Space Launch System (SLS) rocket — could lift off on Sept. 23 or Sept. 27. Those launch dates depend on a number of requirements, including NASA securing a waiver to extend the time needed to check batteries on the SLS' flight termination system (FTS), which is designed to destroy the rocket if it veers off course during launch.
The U.S. Space Force, which oversees the Eastern Range used for Florida rocket launches, requires NASA to test the FTS every 25 days, a process that requires the 322-foot-tall (98 meters) rocket to leave the launch pad and roll back to its hangar. Extending that time frame could allow NASA to avoid weeks of additional delay that would push the Artemis 1 launch into October.
Free said Artemis 1 mission managers submitted a waiver request to the Eastern Range this week. "After meeting with us several times, they've been very gracious and understanding of what we're trying to do," he said in a teleconference today. "Our job is to live to their requirements. That is their range. And it's our job to comply with their requirements."
Free did not reveal how long of an extension NASA is seeking. The agency already had secured one such FTS waiver, pushing the limit from 20 to 25 days.
Artemis 1 is NASA's first mission of the Artemis program to return astronauts to the moon by 2025. It is an uncrewed flight that will test the SLS megarocket and its Orion spacecraft to verify that both are ready to fly astronauts. The first crewed Artemis mission, Artemis 2, will fly astronauts around the moon in 2024, with the Artemis 3 crewed landing to follow a year later. All of that depends on a successful test flight of Artemis 1.
Even with the FTS test waiver, NASA has its hands full trying to get Artemis 1 ready for what will be its third launch attempt. NASA first tried to launch the mission on Aug. 29 but stood down due to an engine cooling issue that was traced to a bad sensor. A persistent liquid hydrogen leak that beat three attempted fixes led to the Sept. 3 launch scrub.
NASA must fix that leak by replacing a seal around an 8-inch (20 centimeters) fuel line on the SLS' core booster. The agency is also working on a smaller fuel connector that saw a different leak on Aug. 29. That work is ongoing this week at the Artemis 1 rocket's Pad 39B launch site at Kennedy Space Center in Florida.
The Artemis 1 SLS rocket must then pass a fueling test to check if the seal fix worked. That test is currently scheduled for no earlier than Sept. 17, but the schedule is tight, Mike Bolger, NASA's Exploration Ground Systems manager, said in today's press conference.
"I would not be surprised to see it slip a day or two," Bolger said. Even if it slips a few days, NASA would still be able to pursue the Sept. 23 or Sept. 27 windows, he added.
NASA has not confirmed if an "inadvertent" manual command that briefly overpressurized the hydrogen fuel line caused the leak, but the agency is investigating the incident. Bolger said new manual processes replaced automated ones during the second attempt and the launch team could have used more time to practice them.
"So we didn't, as a leadership team, put our our operators in the best place we could have," Bolger said. During the Sept. 17 fueling test, NASA will try out a slower, "kinder and gentler" process that should avoid such events.
"We all own the process," Free added. "As far as I was concerned, everybody's finger was on that switch."
Fueling the Artemis 1 SLS rocket with its 736,000 gallons (2.79 million liters) of super-cold liquid hydrogen and liquid oxygen propellant has been a challenge for NASA. Before the two launch attempts, the agency performed four test runs, called "wet dress rehearsals," but didn't manage to check all the desired boxes during any of them.
The next fueling test will be used to check that the leak repairs worked, Bolger said.
"This is the first time we're operating this vehicle," Free said, adding that NASA saw fueling challenges during its space shuttle and Apollo programs. "There are challenges when you try and do this."
Finally, NASA must fit the Artemis 1 launch in when its Deep Space Networkcommunications assets can support the moon flight.
NASA's DART asteroid probe is scheduled to crash into a small asteroid on Sept. 26 and will need to use the Deep Space Network to relay its discoveries back to scientists on Earth. NASA's Artemis 1 launch dates of Sept. 23 and Sept. 27 should avoid any conflict with that mission, Free said.
Meanwhile, SpaceX is planning to launch its next NASA astronaut crew mission, called Crew-5, to the International Space Station on Oct. 3. That's another constraint for when Artemis 1 can fly, Free said.
NASA technically has launch windows for Artemis 1 that run from Sept. 16 to Oct. 4, and then again from Oct. 17 to Oct. 31, with some cutout days in each window.
If NASA is able to pursue a Sept. 23 launch for Artemis 1, liftoff would be scheduled for 6:47 a.m. EDT (1047 GMT) during a 120-minute window. The mission would return to Earth on Oct. 18.
A Sept. 27 launch for Artemis 1 would lift off at 11:37 a.m. EDT (1537 GMT) at the start of a 70-minute window. A launch on that day would lead to a return to Earth on Nov. 5, Free said.
Quelle: SC
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Update: 14.09.2022
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NASA's Artemis 1 moon rocket launch delayed to Sept. 27 at the earliest
Sept. 23 is no longer an option.
NASA's Artemis 1 moon rocket will be grounded for at least four more days.
NASA had been eyeing Sept. 23 or Sept. 27 for the launch of Artemis 1, which will use a Space Launch System (SLS) megarocket to send an Orion capsule on an uncrewed test flight to lunar orbit. But the agency announced in a blog post Monday evening (Sept. 12) that the earlier date is no longer in play; it's now targeting Sept. 27 for the Artemis 1 liftoff, with a possible backup date of Oct. 2.
Artemis 1 was supposed to be aloft already. NASA first tried launching the mission on Aug. 29 but was stymied by an anomalous temperature reading in one of the SLS' first-stage RS-25 engines. The mission team soon traced that issue to a faulty temperature sensor and got the SLS and Orion ready for another try on Sept. 3. But a leak of liquid hydrogen propellant scuttled that liftoff attempt as well.
The leak occurred at a "quick disconnect," an interface linking the SLS core stage with a propellant line coming from the rocket's mobile launch tower. The Artemis 1 team replaced two seals around the quick disconnect last week and wrapped up other repair work related to the issue over the weekend, NASA officials wrote in the update.
NASA is now gearing up for an SLS fueling test, which will pump supercold propellant into the SLS to show that the leak has indeed been fixed. The agency had been targeting Sept. 17 for that test, but it has now been pushed back to no earlier than Sept. 21.
"The updated dates represent careful consideration of multiple logistical topics, including the additional value of having more time to prepare for the cryogenic demonstration test, and subsequently more time to prepare for the launch," NASA officials wrote in Monday's blog post(opens in new tab). "The dates also allow managers to ensure teams have enough rest and to replenish supplies of cryogenic propellants."
The Artemis 1 stack remains at Pad 39B at NASA's Kennedy Space Center in Florida, but it may end up having to roll back to KSC's huge Vehicle Assembly Building (VAB). The U.S. Space Force, which oversees the Eastern Range for rocket launches, certified Artemis 1's flight termination system (FTS) for just a 25-day stretch — and that time is already up.
NASA has requested an extension for the certification of the FTS, which is designed to destroy the Artemis 1 stack if it veers off course during liftoff. If that request is denied, the vehicle will have to be rolled off Pad 39B to the VAB, the only place where the testing required for recertification can take place. (Artemis 1 might have to go back to the VAB for repairs anyway, if the fixes made at the pad don't end up sticking.)
"NASA is continuing to respect the Eastern Range’s process for review of the agency’s request for an extension of the current testing requirement for the flight termination system and is providing additional information and data as needed," NASA wrote in Monday's update. "In parallel, the agency is continuing preparations for the cryogenic demonstration test and potential launch opportunities, should the request be approved."
NASA has already received one such FTS extension, from 20 days to 25 days.
The two upcoming liftoff dates for Artemis 1 are close to that of SpaceX's Crew-5 astronaut mission for NASA, which is scheduled to launch toward the International Space Station from KSC's Pad 39A on Oct. 3.
"Teams are working the upcoming commercial crew launch in parallel to the Artemis 1 planning, and both launch schedules will continue to be assessed over the coming weeks," NASA officials wrote in Monday's update.
Quelle: SC
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Update: 16.09.2022
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NASA delays SLS tanking test, next launch opportunity
NASA’s Space Launch System moon rocket on its launch pad. Credit: Michael Cain / Spaceflight Now / Coldlife Photography
NASA said Monday it is now targeting Wednesday, Sept. 21, for a critical fueling test on the Space Launch System moon rocket, which could allow for another attempt to launch the unpiloted Artemis 1 lunar test flight as soon as Sept. 27, assuming engineers find no problems and the Space Force approves an extension for the rocket’s range safety system. The updated schedule is a four-day delay for the SLS tanking test and next launch opportunity.
“The updated dates represent careful consideration of multiple logistical topics, including the additional value of having more time to prepare for the cryogenic demonstration test, and subsequently more time to prepare for the launch,” NASA said Monday. “The dates also allow managers to ensure teams have enough rest and to replenish supplies of cryogenic propellants.”
Ground crews at NASA’s Kennedy Space Center completed repairs to a hydrogen leak at the launch pad over the weekend, the agency said Monday. Teams discovered the leak during a launch attempt Sept. 3, forcing NASA to delay the start of the Artemis 1 lunar test flight until the next launch period. NASA has cycles of roughly two weeks of launch opportunities each month due to a range of technical factors, primarily the position of the moon in its orbit around the Earth.
Technicians last week replaced two seals in liquid hydrogen lines routed between the rocket’s mobile launch platform and the core stage, then re-connected the fuel feed line between the launch pad and the launch vehicle over the weekend. Testing is on tap this week to ensure there is a tight bond between the ground-side and rocket-side umbilical plates at ambient conditions.
The cryogenic loading test on the rocket now planned for Sept. 21 will expose the umbilical connection to super-cold temperatures as liquid hydrogen flows into the rocket. The liquid hydrogen is chilled to minus 423 degrees Fahrenheit (minus 253 degrees Celsius).
The shape and size of seals and gaskets can change when exposed to super-cold temperatures, creating a leak path that wasn’t detectable at ambient temperatures. A molecule of liquid hydrogen, created by bonding two hydrogen atoms together, is one of the tiniest known in the universe, and leak through gaps impermeable to other molecules.
The SLS moon rocket’s core stage contains 537,000 gallons of liquid hydrogen fuel and 196,000 gallons of super-cold liquid oxygen as an oxidizer. The same propellants power the SLS upper stage, with much smaller tanks. All four propellant tanks will be loaded in the Sept. 21 tanking test.
“The demonstration will allow teams to confirm the hydrogen leak has been repaired, evaluate updated propellant loading procedures designed to reduce thermal and pressure-related stress on the system, conduct a kick-start bleed test, and evaluate pre-pressurization procedures,” NASA said Monday.
The kick-start bleed test and pre-pressurization procedures will verify countdown steps that were unaccomplished during dress rehearsals earlier this year. The hydrogen bleed line needed to thermally condition the four core stage engines leaked during a June countdown rehearsal, and was repaired when the rocket returned to the Vehicle Assembly Building. NASA scrubbed the first Artemis 1 launch attempt Aug. 29 when sensor data indicated one of the engines was not reaching the proper temperature during the hydrogen bleed procedure.
NASA determined the temperature reading on the engine was from a bad sensor, and pressed ahead with a second launch attempt Sept. 3. But the launch team never got to the kick-start bleed milestone in the Sept. 3 countdown due to the hydrogen leak encountered during fuel loading.
The space agency also continues to work with the U.S. Space Force’s Eastern Range on a request to extend the range’s certification of batteries on the SLS moon rocket’s flight termination system, which would destroy the launcher if it veered off course after liftoff. The range must approve the battery certification — initially 20 days, then increased to 25 days and now would need to cover at least 45 days — in order for NASA to proceed with attempts in late September and early October.
“NASA is continuing to respect the Eastern Range’s process for review of the agency’s request for an extension of the current testing requirement for the flight termination system and is providing additional information and data as needed,” the agency said Monday. “In parallel, the agency is continuing preparations for the cryogenic demonstration test and potential launch opportunities, should the request be approved.”
If the range doesn’t approve the battery certification extension, NASA will need to roll the SLS moon rocket back to the Vehicle Assembly Building, pushing the Artemis 1 launch date into the second half of October or November. The next launch period opens Oct. 17 and runs through Oct. 31, followed by another series of launch dates starting Nov. 12.
NASA said a launch attempt Sept. 27, if approved by the range, would have a launch window opening at 11:37 a.m. EDT (1537 GMT). If the mission blasts off Sept. 27, the Orion spacecraft would wrap up its unpiloted test flight to the moon and back with a splashdown in the Pacific Ocean on Nov. 5.
A backup launch opportunity could be available Oct. 2, with a 109-minute launch window opening at 2:52 p.m. EDT (1852 GMT), resulting in splashdown of the Orion spacecraft Nov. 11.
NASA’s Artemis team is also working around schedules for other launches. NASA and SpaceX plan to launch the next crew to the International Space Station on Oct. 3 on a Falcon 9 rocket from pad 39A at Kennedy, less than 2 miles south of pad 39B, where the Artemis 1 moon rocket is located. Launch operations at each pad can temporarily halt work at the neighboring launch facility, which must be evacuated when a rocket is taking off nearby.
“Teams are working the upcoming commercial crew launch in parallel to the Artemis 1 planning and both launch schedules will continue to be assessed over the coming weeks,” NASA said. “NASA and SpaceX will review the Artemis 1 and Crew-5 prelaunch processing milestones to understand any potential impacts.”
Quelle: SN
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Update: 22.09.2022
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Liquid Hydrogen in Replenish, Teams Move Ahead with ICPS Loading
The Space Launch System’s core stage liquid hydrogen tank is now full and is being replenished as some of the supercold propellant boils off. Since resuming liquid hydrogen fast fill operations, the rate of the hydrogen leak at the tail service mast umbilical quick disconnect has remained within allowable rates. The core stage liquid oxygen tank also is in the replenish phase.
Teams are pressing ahead with operations to load propellants into the interim cryogenic propulsion stage of the rocket. Once liquid hydrogen and liquid oxygen loading on the stage reach the replenish phase, the pre-press test, one of the objectives for today’s demonstration, will occur.
The pre-pressurization test will bring the core stage liquid hydrogen tank up to the pressure level it will experience just before launch while engineers calibrate the settings for conditioning the engines at a higher flow rate, as will be done during the terminal count on launch day.
Artemis Cryogenic Test: Core Stage LH2 Underway; LOX Fill and Engine Bleed Test Complete
Fast fill continues for the Space Launch System (SLS) rocket’s core stage liquid hydrogen (LH2) tank at a reduced pressure as teams monitor the area where the hydrogen leak was detected. Fast fill is complete for the core stage liquid oxygen (LOX) tank and engineers have completed the engine bleed test, which flows supercold LH2 to the four RS-25 engines, bringing their temperature down to the conditions required for launch.
NASA's Artemis moon rocket makes it through critical fueling test despite hydrogen leak
NASA's leak-plagued Space Launch System moon rocket ran into initially worrisome problems during a fueling test Wednesday, but engineers "managed" a fresh leak in a fitting that derailed a Sept. 3 launch try and were able to fill the huge booster with a full load of 750,000 gallons of supercold propellants.
They also carried out two other critical tests, verifying their ability to properly chill the rocket's four hydrogen-fueled engines as required for flight and successfully pressurizing the core stage hydrogen tank to flight levels.
Launch Director Charlie Blackwell-Thompson would not speculate on whether NASA might press ahead toward a September 27 launch date as earlier discussed, saying she wanted her team to review data from the test before drawing any conclusions. But she said she was "extremely encouraged by the test today."
NASA's Space Launch System mega rocket atop pad 39B at the Kennedy Space Center Wednesday. Engineers carried out a full-scale fueling test to verify repairs to fix a hydrogen leak that derailed a September 3 launch try, yet another leak cropped up in the same system. This time around, engineers were able to use different flow rates and pressures to fully fuel the giant rocket.NASA
"I don't like to get ahead of the data, so I'd like the team to have the opportunity to go look at it to see if there are changes we need to make to our loading procedures, our timelines or if we're good as is," she said.
The discussion could prove challenging given the seal blamed for the earlier launch delay was replaced and the same system, at least initially, leaked again Wednesday.
But even if the team concludes September 27 is a viable target for the rocket's maiden flight, it might not be enough. The Space Force Eastern Range, which oversees all military and civilian launches from Florida, has not yet ruled on a request from NASA to waive a requirement to inspect batteries in the rocket's self-destruct system.
The batteries cannot be accessed at the launch pad and without a waiver, NASA will be forced to haul the 332-foot-tall SLS rocket back to the Kennedy Space Center's iconic Vehicle Assembly Building, delaying launch for a month or more.
The long-awaited Artemis 1 mission is designed to send an unpiloted Orion crew capsule on a 40-day voyage around the moon and back to pave the way for the first piloted Artemis mission in 2024. If all goes well, NASA plans to land two astronauts near the moon's south pole in the 2025-26 timeframe, the first in a sustained series of missions.
But engineers have been bedeviled by elusive hydrogen leaks and other issues during the rocket's run-up to launch. Already years behind schedule and billions over budget, the SLS rocket was first hauled out to launch pad 39B on March 17 for a fueling test to clear the way for launch. But back-to-back scrubs were ordered April 3 and 4 because of multiple unrelated problems.
Liquid oxygen and hydrogen propellants flow into the Space Launch System's huge core stage through retractable 8-inch-wide lines that extend from two so-called tail service mast umbilicals (at left) to quick-disconnect fittings attached to the side of the booster. A leak in the hydrogen fitting caused initial problems during a fueling test Wednesday, but engineers were able to re-seat a suspect seal and successfully load the rocket with propellants.NASA
A third test on April 14 was called off because of a hydrogen leak near the core stage fuel line quick-disconnect, and the rocket was rolled back to the VAB for servicing. It returned to the launch pad in early June only to suffer more problems during a June 20 fueling test, when engineers were unable to cool the rocket's engines because of a stuck valve in a different system.
The rocket was returned to the VAB for repairs in early July and hauled back to the pad in mid-August for what NASA hoped would be its maiden flight. But a launch try on August 29 was called off because of more hydrogen issues and again on September 3 when the 8-inch quick-disconnect fitting leaked.
In the wake of the second launch scrub, NASA managers opted to take the fitting apart at the launch pad, replace an internal seal, re-assemble the hardware and carry out a fueling test to verify the seal's integrity. Hydrogen leaks typically show up only when the plumbing is exposed to cryogenic temperature — minus 423 degrees Fahrenheit in this case,
Oxygen vapor billows from vents in the side of the Space Launch System rocket as propellants were loaded into the booster's upper stage.NASA
The repair work was completed last week and the test began normally enough Wednesday, with oxygen and hydrogen flowing into separate core stage tanks at low rates. In an effort to ease the thermal shock when transitioning to "fast fill" mode, the loading sequence was slowed down and flow rates reduced to ease stresses on the hardware.
But when the flow rate and pressures increased, sensors detected an immediate buildup of gaseous hydrogen in a containment housing around the just-repaired quick-disconnect fitting, indicating a leak. Sensors detected concentrations of up to 7%, well above the 4% safety limit.
Engineers then opted to warm up the fittings before restarting the hydrogen flow in hopes of coaxing the internal seal to "re-seat" itself. When flow resumed, a leak was still present, but it was well below the 4% threshold and engineers were able to press ahead, eventually topping off the hydrogen tank with a full load of 730,000 gallons.
A close examination of sensor data showed that in a reversal of the initially observed behavior, the leak rate went down as pressure increased. That's how the fitting is designed to operate, suggesting efforts to re-seat the seal were at least partially successful.
With the core stage hydrogen and oxygen tanks full, engineers pressed ahead with loading the SLS rocket's upper stage and in the meantime carried out the pressurization and engine cooling tests.
Another hydrogen leak was reported near a 4-inch quick-disconnect fitting used for the cooling test. While engineers already had agreed to press ahead with the observed concentration, it would have halted an actual launch countdown. No word yet on what impact, if any, that issue might have on launch planning.
Quelle: CBS News
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Update: 25.09.2022
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NASA delays next Artemis I launch attempt due to Tropical Storm Ian
Update: NASA has decided to call off the Tuesday, Sept. 27, Artemis I launch attempt due to impacts from Tropical Storm Ian, which is expected to strengthen to hurricane status early Monday. A backup attempt on Sunday, Oct. 2, is likely to be unfavorable as well but depends on several factors.
NASA plans on pushing forward with an attempt at launching its Artemis I moon mission next week, though forecasted weather conditions are unlikely to be favorable as a tropical system slowly takes aim at Florida.
After two previous launch attempts were scrubbed by technical issues, teams at Kennedy Space Center conducted a successful fueling test at pad 39B this week. With the issues – mainly related to liquid hydrogen – worked out, officials are pushing forward with a liftoff during the next 70-minute window that opens at 11:37 a.m. EDT Tuesday, Sept. 27.
NASA officials Friday said they were confident the rocket was ready to launch. But a storm developing in the Caribbean, likely to become Hurricane Hermine over the weekend or early Monday, is introducing more uncertainties beyond hardware. A Friday forecast issued by the Space Force shows 80% "no-go" conditions during Tuesday's Artemis I launch window.
"Since (the test), we've been keeping a close eye on what's called Tropical Depression No. 9," Mike Bolger, NASA's manager of ground systems, said during a Friday teleconference. "Our Plan A is to stay the course and get a launch off on Sept. 27, but we realize we also need to really pay attention and think about Plan B."
Bolger said he and other mission managers would need to make a decision based on the storm's latest track Saturday morning or afternoon at the latest. If NASA needs to dodge the storm, the 322-foot Space Launch System rocket will need to roll back to the Vehicle Assembly Building.
"NASA will make a decision on whether to remain at the launch pad or rollback using incremental protocols to take interim steps necessary to protect people and hardware with a final decision anticipated no later than Saturday afternoon," NASA said in a release late Friday.
One of the main factors involved in making a final decision is forecasted winds: if the National Hurricane Center, Space Force forecasters, and other officials see the potential for peak gusts of 74 knots (about 85 mph), teams will have to roll back to the VAB. That process will take about three days.
"We would need a couple days to pivot from the tanking text and exit the launch configuration for rollback to the VAB," Bolger added.
A backup window is available at 2:52 p.m. EDT Sunday, Oct. 2, but the forecast for that opportunity will not be available until next week. Beyond that, the next opportunity to fly won't come until Oct. 17 and closes again after Oct. 31.
SLS's flight termination system, designed to destroy the rocket in the event of an emergency, is certified by the Space Force. As the agency responsible for public safety, it must sign off on the system's batteries every 25 days. SLS's current certification expired earlier this month and re-certification work can only be done inside the VAB.
The Space Force, which oversees launch safety, gave NASA a waiver to go forward with launch attempts Tuesday and Oct. 2.
Artemis I is NASA's first mission under its new return-to-the-moon program. If SLS successfully launches its uncrewed Orion capsule to the moon and back, that will pave the way for astronauts to do the same for Artemis II no earlier than 2024. Artemis III will follow and put two people on the lunar surface sometime before 2030.
"We've got a robust design, but we want to protect the vehicle," SLS Chief Engineer John Blevins said. "We're just going to look at what the forecast is ... and certainly we'll have to make a decision over the next 24 hours."
Quelle: Florida Today
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Update: 28.09.2022
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NASA postpones Artemis 1 launch because of tropical storm
NASA will not attempt a launch of the SLS on the Artemis 1 mission Sept. 27 but will wait one more day before deciding to roll the rocket back to the Vehicle Assembly Building as Tropical Storm Ian heads towards Florida. Credit: NASA/Ben Smegelsky
WASHINGTON — NASA has called off plans to attempt to launch the Artemis 1 mission on Sept. 27 as a tropical storm, with the potential to become a major hurricane, heads for Florida.
NASA announced Sept. 24 it would not proceed with the next launch opportunity for the mission, which was Sept. 27 at 11:37 a.m. Eastern. It cited the threat posed by Tropical Storm Ian, currently in the Caribbean Sea. Forecasts by the National Hurricane Center show the storm moving north, then curving northeast to reach southern and central Florida by the middle of the week as a major hurricane.
While NASA won’t proceed with a launch on Sept. 27, it deferred a decision on rolling the Space Launch System rocket and Orion spacecraft back to the Vehicle Assembly Building (VAB) at the Kennedy Space Center to protect it from the storm, while continuing preparations for a rollback. NASA said in the statement it would wait until Sept. 25 to make that decision “to allow for additional data gathering and analysis.”
At a Sept. 23 briefing, NASA officials said their preference was to leave the SLS at Launch Complex 39B. Doing so could preserve a final launch opportunity in this window Oct. 2, while rolling the vehicle back to the VAB could make it difficult to attempt a launch in the next window in the latter half of October.
At the briefing, Mike Bolger, manager of the Exploration Ground Systems program at NASA, noted the vehicle is rated to handle wind gusts of up to 74 knots (137 kilometers per hour) at the pad. “Right now, we don’t have a forecast that shows winds gusting higher than 74 knots coming across the Kennedy Space Center,” he said.
“We do have a certified design with factors of safety to those peak gusts,” said John Blevins, SLS chief engineer. “Ultimately we have a pretty robust vehicle, and we’ll just have to keep looking at that forecast to see if we fall within our certified parameters.”
Agency officials seems curiously dismissive of the threat posed by the storm, which at the time of the briefing was still an unnamed tropical depression but forecast to strengthen significantly in the coming days. “It’s not even a named storm. It’s Tropical Depression Number Nine,” said Tom Whitmeyer, deputy associate administrator for common exploration systems development at NASA Headquarters. “It’s very early in, and some of the traces we see go in different directions and go at different speeds.”
“I wish we were better at predicting weather absolutely five days in advance,” he added, noting that if he could, “I would pretty much quit this job to go work for the weather bureau.”
In a statement after the briefing, NASA appeared to do some damage control. “NASA is grateful to its agency partners at NOAA, United State Space Force and the National Hurricane Center for giving us the highest quality products to protect our nation’s flight test to return us to the Moon,” the agency stated.
Tanking test update and FTS waiver
Weather turned out to be the biggest constraint for the launch after overcoming issues with hydrogen leaks and securing a waiver for the rocket’s flight termination system.
At the Sept. 23 briefing, officials said they were satisfied with the tanking test two days earlier where the rocket’s core and upper stages were filled with liquid hydrogen and liquid oxygen. NASA said the test accomplished all the objectives despite hydrogen leaks encountered during it.
“All in all, it was a good day. We’re very happy with the results,” said Brad McCain, vice president and general manager of Jacobs Space Operations Group. “We’re very optimistic about our next launch attempt.”
He and others said they were still in the process of learning how to best load propellants into the vehicle, something that requires practice. “The pressure and temperature of that seal — any seal in cryogenics — is always going to be tricky,” said Blevins. “Sometimes it takes a while to find out the stability points.”
With the shuttle, said McCain, “it took a lot of tankings to get it right, get it consistent.”
Blevins said that NASA also overcame another obstacle to the launch by securing a waiver from the U.S. Space Force, which operates the Eastern Range, for the SLS flight termination system (FTS). That system was certified only through the end of the previous launch window that ended in early September, but NASA had been in discussions with the range to show that the system would still operate should the vehicle launch in late September or early October.
“We have received approval for the launch attempts that we have on the books,” which at the time was Sept. 27 and Oct. 2, Blevins said. “They did a lot of work to help us get to where we are.”
He did not state if that waiver would be good if the launch slips later in the year. However, should NASA decide to roll the SLS back to the VAB, Whitmeyer said that workers would service the FTS and effectively restart the clock on its certification for a later launch attempt.
“I don’t want to go into any details because it’s just not pertinent here,” Blevins said of the work to secure the FTS waiver, adding that disclosing any details would be “silly” given the number of parameters involved in the Space Force analysis of the waiver request. “They have an incredible mission and they do a good job at it. I’m really glad we had enough information to provide the public safety assurance they get to grade.”
Quelle: SN
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Update: 4.10.2022
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NASA rules out launch of Artemis 1 moon rocket before mid-November
NASA’s Space Launch System moon rocket rolls into High Bay 3 of the Vehicle Assembly Building on Sept. 27 to take shelter from Hurricane Ian. Credit: NASA/Joel Kowsky
NASA said Friday that officials have ruled out launching the agency’s first giant Space Launch System moon rocket and Orion spacecraft before mid-November, following the rocket’s return to the hangar at Kennedy Space Center for safekeeping from Hurricane Ian.
Ground teams at Kennedy completed initial inspections of the Artemis 1 moon rocket Friday after the spaceport experienced tropical storm force winds and heavy rain. Hurricane Ian, which struck Southwest Florida as a Category 4 storm, weakened to a tropical storm before reaching the Space Coast. The center of circulation passed directly over Kennedy Space Center.
NASA said the Artemis 1 moon rocket inside the Vehicle Assembly Building escaped damage, and ground facilities are in “good shape with only minor water intrusion identified in a few locations.”
Workers will next extend access platforms around the SLS moon rocket and Orion spacecraft inside High Bay 3 of the Vehicle Assembly Building. That will enable teams to perform additional inspections and prepare for the next launch attempt, which is now expected in November.
Agency officials said they are now targeting a launch period that opens Nov. 12 for the next opportunity to launch the Artemis 1 test flight. Artemis 1, which will fly without astronauts, is the inaugural demonstration flight of the huge Space Launch System moon rocket, and the first flight of an Orion crew capsule around the moon. If it goes well, Artemis 1 will pave the way for future crew missions to the moon, beginning with Artemis 2 as soon as 2024.
“Fortunately, it was down to about 55-knot winds when it hit us, and we had some flooding and stuff, but overall we’re looking good,” said Bob Cabana, NASA’s associate administrator. “And it was really good that we got that big rocket back in the barn. Ian track right between pad 39A and B is it went across, and it was great knowing that SLS and Orion were safe getting ready for Artemis 1.”
NASA hauled the 322-foot-tall (98-meter) moon rocket rocket off Launch Complex 39B and back to the VAB early Tuesday, before weather conditions deteriorated at Kennedy. It was the sixth time the SLS moon rocket has moved between the VAB and the launch pad since March, and engineers prefer to minimize the moves to limit wear and tear on the rocket from the vibrations of riding on top of the crawler. But in the end, NASA decided it was more risky to leave the rocket on the pad with tropical storm or hurricane force winds possible at Kennedy Space Center this week.
Managers hoped to launch the Artemis 1 test flight before the end of the current launch period Oct. 4, but the rollback to the VAB prevented that. And the moon rocket won’t be ready to head back to the launch pad in time for the next launch period from Oct. 17-31.
The November launch period opens Nov. 12 and runs through Nov. 27. NASA has about two weeks of launch availability in each Artemis launch period, followed by around two weeks when the mission would be not be feasible. The primary driver of the launch periods is the position of the moon in its 28-day orbit around Earth, but there are other factors, including NASA’s requirement for the trajectory to culminate in a splashdown of the Orion spacecraft in the Pacific Ocean in daytime.
“Focusing efforts on the November launch period allows time for employees at Kennedy to address the needs of their families and homes after the storm and for teams to identify additional checkouts needed before returning to the pad for launch,” NASA said.
The launch dates and times in the November launch period for Artemis 1. Credit: Spaceflight Now
Engineers plan several tasks with the rocket back in the VAB, including swapping out batteries on the flight termination system, which range safety teams would use to destroy the launch vehicle if it flies off course after liftoff and threatens populated areas. The battery changeout work will require technicians to open an access door and enter the “intertank” section of the SLS core stage, the volume between the core stage’s liquid hydrogen and liquid oxygen tanks.
The U.S. Space Force’s Eastern Range, which is responsible for public safety for all launches from Florida’s Space Coast, granted NASA a waiver last week to extend their certification of the flight termination system batteries long enough to enable Artemis 1 launch attempts through early October. The batteries were originally only certified for 25 days, long enough to allow Artemis 1 launch attempts through early September.
Changing out and re-testing the batteries is only possible with the rocket back inside the VAB.
NASA engineers will also spend the next few weeks assessing parts of the Space Launch System moon rocket and Orion spacecraft that could have lifetime limitations. NASA began stacking the rocket’s solid-fueled boosters on the mobile launch platform in November 2020, and capped off stacking of the rocket with the addition of the Orion spacecraft last October.
Engineers are analyzing the condition of pre-packed propellants inside the Space Launch System’s solid rocket boosters, which originally were only certified for 12 months once stacked on the launch platform. That lifetime limit has been extended by engineering reviews, and John Blevins, the SLS program’s chief engineer, recently said the boosters should be good for at least a few more months.
There is also a limit for how long hypergolic hydrazine and nitrogen tetroxide propellants can be loaded on the service module of the Orion spacecraft. The hypergolic propellants will be used for in-space maneuvers by the Orion propulsion system during the trip to the moon and back.
“We have a list of, I’d say, about 20 things that we’re looking at that have different durations in which we have to revisit them,” said Jim Free, associate administrator of NASA’s exploration systems mission development division. “We’re always looking at batteries in general. Obviously, we’re looking at some of the hypergol (propellant) storage on the service module. We want to make sure that we’re staying on top of and understanding the long term implications of that.”
Engineers are evaluating the conditions different components have been exposed to since stacking began on the Artemis 1 moon rocket, Free said.
With winter approaching in the northern hemisphere, most of of the Artemis 1 launch windows in the next few months will be at night. The first days of the November launch period all come with middle of the night launch times.
“I think our preference is to launch in the daylight,” Free said. “I think we feel like the visuals that we get from our long range tracking cameras are of benefit to us. We do have obviously some ways we can view the vehicle if we were to launch in the dark. I think we look at the risk versus benefit trade. So our preference is probably a daylight launch but we don’t rule out the nighttime launch either.”
Quelle: SN
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Update: 14.10.2022
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NASA's Artemis I moon mission just got shorter and is now scheduled for liftoff in November
NASA is now targeting mid-November for its next launch attempt of the Space Launch System rocket and Orion capsule for the debut Artemis I mission around the moon and back.
Liftoff is slated for the middle of the night on Monday, November 14 at 12:07 a.m. EST — a deviation from the previous two liftoff attempts scheduled during daylight.
The agency has also requested backup nighttime launch opportunities for Wednesday, Nov. 16, and Saturday, Nov. 19.
Launching during any of these windows, however, depends on getting the 322-foot rocket stacked with an uncrewed Orion capsule back to launch pad 39B at Kennedy Space Center to complete a slew of pre-launch procedures.
The agency said Wednesday that while the rocket remains in the VAB teams still have to "perform standard maintenance to repair minor damage to the foam and cork on the thermal protection system and recharge or replace batteries on the rocket, several secondary payloads, and the flight termination system."
The flight termination system, designed to destroy the rocket in the event of an emergency, is certified by the Space Force. The agency responsible for public safety will need to sign off on the system's batteries before the SLS once again sets off on its path to launch.
If those activities are completed in time, the rollout could take place as early as Friday, Nov. 4.
Two previous attempts to launch the Artemis I mission in late August and early September were called off due to technical issues. First, a faulty engine sensor, then a significant hydrogen leak that hindered the completion of fueling.
Liftoff on Monday, Nov. 14, would occur during a window that extends for just 69 minutes. The backup opportunities on Nov. 16 and 19 offer a two-hour launch window and more wiggle room for NASA to mitigate any issues that may arise during the countdown.
A Nov. 14 liftoff would result in a short duration Artemis I mission lasting just 25-and-a-half days. Previous launch attempts positioned Artemis I for an extended mission of around 43 days.
If all proceeds as planned for a mid-November launch, the Orion spacecraft can be expected to return for a splashdown in the Pacific Ocean off the coast of California sometime in mid-December.
Artemis II will do the same but with astronauts, while Artemis III, expected sometime before 2030, aims to deliver at least two astronauts to the moon's surface.
Quelle: Florida Today
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Update: 27.10.2022
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NASA’s big plan: Move ahead on Artemis program as first launch nears
NASA's Marshall Space Flight Center in Huntsville was and remains key to getting the agency's Space Launch System (SLS) launching regularly. In this NASA image, a section of a first-generation fuel tank for SLS was unloaded from NASA’s barge Pegasus at the Marshall Space Flight Center in Huntsville, Ala.., The nearly 70-foot-long liquid oxygen (LOX) tank was stress tested in test stand at Marshall.PM Credit
NASA has ordered three more Orion spacecraft from Lockheed Martin for a total of six in a move signaling the agency’s commitment to moving ahead with plans to return to the moon and then venture farther with its new rocket.
Orion and its service vehicle are the upper parts of the package that carry the astronauts into deep space. NASA is now contracted with Lockheed Martin for up to 12 vehicles.
Missions one through three will launch an un-crewed Orion around the moon, a crewed mission on the same journey and a third trip to land astronauts on the surface. One of its major goals is testing a new heat shield that must protect the capsule’s interior for astronauts aboard.
NASA is attempting to get the first, un-crewed Artemis launch off from Kennedy Space Center in Florida before the end of this year. Its next launch date attempt is Nov. 14 with a 69-minute launch window that opens at 11:07 p.m. CST. NASA says “minimal work is required to prepare the rocket and spacecraft to roll out to Launch Pad 39B.
Ordering the upper stages in packages of three lets NASA “benefit from efficiencies that become available in the supply chain over time,” the space agency says.
Engineers are preparing the Orion crew and service modules now for Artemis II, the first that will carry astronauts, NASA said. They have been “powered on” and are being prepared for tests of those systems.
Last week, NASA’s Super Guppy aircraft delivered the heat shield for Artemis III from Lockheed Martin’s plant in Waterton, Col., to Kennedy Space Center. The shield – a new model for NASA – is another of the key item tests on the first launch.
The current Orion count is one capsule on top of Artemis I and two others under assembly at NASA’s Kennedy Space Center. Work is also under way on Artemis IV and Artemis V.
As for the rocket that will lift those Orions, NASA said this summer it plans to transfer space launch production, testing, manufacturing, and transport for up to 10 Artemis launches to a new contractor: Deep Space Transport LLC, a joint venture of Boeing and Northrop Grumman. NASA said it can’t put those rockets out for bid yet because of the proprietary processes used to build them.
NASA has also said its SLS work force “will continue to provide expertise for the first four Artemis missions and for future Artemis missions.” That workforce includes the SLS team at Huntsville’s Marshall Space Flight Center.
“We have a big job ahead of us to fly the first four Artemis missions and develop the new exploration upper stage,” Marshall Center Director Jody Singer said in July. “While NASA transitions the contracting approach for long-term SLS operations, the talented team that brought the rocket to the launchpad will also be needed for other projects necessary for the agency’s exploration missions.”
