A high-rise mobile platform for the agency's space launch system arrived Friday at the launch pad 39B at the Kennedy Space Center in Florida. In conclusion, the managers should declare that the spaceport's floor systems are ready to to support the first SLS launch campaign by the end of the year.
The Mobile Launcher is a moving platform that will transmit the 98 meter high space launch system from the vehicle assembly building to the launch pad. The $ 1 billion tower is one of the tallest structures in Cape Canaveral, and NASA originally built it for the Ares-1 rocket, a single-booster carrier that was demolished in 2010 before ever going on an orbital mission ,
The roll-out of the Mobile Launcher for the Pad 39B this week includes nine months of electrical and mechanical testing in the vehicle assembly building. Now that the tower's platform and compatibility with the VAB has been checked to stack the Space Launch System, engineers now want to make sure it works on the launch pad.
"It's the next big step right before the final exam before we finish," said Cliff Lanham, NASA's senior project manager for the Mobile Launcher. "So we're all very excited, I know our task force is ready to handle it so it can handle the rocket, and everyone is excited about it."
The mobile launch tower for the NASA space launch system Arrived at the Kennedy Space Center at Pad 39B today for final swing arm, propellant flow, and silencing testing before being declared operational .com / sDNVpKBxpu
– Spaceflight Now (@SpaceflightNow) June 29, 2019
But Exactly When NASA Can It Finally, the use of the Mobile Launcher is hard to predict, officials said Thursday Difficulties assembling Boeing's Louisiana-based core of the space launcher have called into question a first launch of the new rocket in 2020, three years later than originally planned
NASA is developing the space launch system for astronaut deployments on moon journeys – with the goal of landing humans within five years – the space agency wants to congregate via a mini space station on a high moon orbit.
With no crew on board, this could happen before the end of 2020, but any technical issues identified in several critical upcoming ground tests could delay launch only in June 2021, according to a Government Accountability report released earlier this month Office emerges.  NASA officials said the rollout of the Mobile Carrier on Pad 39B was to be the last time that the mammoth structure reached the launch pad before the ground crews stacked the space carrier system on the platform in preparation for the first flight.
The SLS core stage is powered by four RS-25 main engines, two solid-fuel rocket boosters and one RL10 upper-stage engine. When launched, the rocket will produce a boost of up to 8.8 million pounds.
The first SLS launch, named Artemis 1, will send an unmanned Orion crew capsule on a shakedown cruise to the Moon and back. The Orion spacecraft and its service module will swing up to 100 kilometers from the lunar surface and then travel to a farther orbit about 70,000 kilometers from the moon before returning to Earth.
The second The SLS / Orion flight will transport 2022 or 2023 astronauts on a loop around the Moon and back to Earth, followed by the Artemis 3 mission in 2024, with the astronauts attempting the first landing on the Moon since 1972 could.
] One of NASA's Apollo-era diesel-powered crawler vehicles carried the 10.5 million pound launch vehicle from the cavernous vehicle assembly building to base 39B. Both facilities at the Florida Spaceport were built in the 1960s for the Apollo Lunar Program and later modified for the Space Shuttle and the Space Launch System.
The crawler crew shared the 6.8-kilometer, two-day journey at 12:00 pm CET (0400 GMT) Thursday with the rollout of High Bay 3 in the vehicle assembly building where the tower has been located since last September. The Mobile Launcher hit the stone-covered crawler at a top speed of 1.3 km / h (70 ft / min) and hit the gate to Pad 39B late Thursday morning.
The Mobile Launcher was finished driving up the ramp to Pad 39B on Friday morning. A laser alignment system helped the crawler crew guide the Mobile Launcher into position and then lower it on the launch pad over six pedestals.
NASA plans to leave the Mobile Launcher on Pad 39B until about the end of September. During the three-month campaign, engineers will conduct a series of tests, including retracting the wings to mimic their function during a start-up countdown, and for the first time cryogenic liquid hydrogen and liquid oxygen propellant through the structure's piping.
"We will connect all our systems to the pad systems and test whether the mobile launcher and the pad work together properly," said Lanham. "For example, we test water flows, noise suppression and IOP systems (Ignition Overpressure). We will do cryogenic flows out there too.
"We will do the arm swing for the crew because we can not fully test the swingarms in the VAB, so we'll test them out there. We will also do some end-to-end tests on the electrical systems. We'll make sure we can get from the LCC (Launch Control Center) to the pad, "Lanham said. "We have planned a simultaneous arm swing in which we swing three of the arms together and make sure the hydraulic system can handle it."
Unlike the mobile launch tables used by the Space Shuttle, the SLS mobile launch vehicle launcher incorporates a gigantic skyscraper-like structure on the platform itself. The 115-meter Mobile Launcher features a metal tower on a two-story base with six swivel arms. retreating from the rocket before take-off.
In the shuttle era, Pads 39A and 39B had fixed naval towers for access by astronauts, ground personnel, and swivel arms to the vehicle. The Saturn 5 moon rocket of the Apollo program used a similar pad setup as the SLS, but the mobile tower of the Saturn 5 had nine pivot arms.
The SLS tower and platform contain nearly 1,000 pieces of ground equipment, routing energy, data and water, propellants, air conditioners, and other utensils for the launch vehicle and capsule of the Orion crew.
Once the engineers have completed the tests on the launch pad this summer, the mobile launcher will return for some time to the bay 3 in the vehicle assembly building. Last checkouts, including a demonstration in which cranes will for the first time display dummy segments of an SLS Stack booster on the platform.
"This is a great day for us," said Darrell Foster, Manager Exploration Ground Systems Integration at KSC. "In my view, this is our start day … From the point of view of hardware development, we live for it, for these big milestones and for the compilation of the parts. It's like a puzzle. "
On the launch pad 39B, workers have installed new refractory bricks in the flame trench and used a new flame arrester to lift the exhaust gases from the SLS main engines and solid rocket boosters heading north. NASA added new work platforms in the VAB high bay warehouse to allow employees to reach the SLS during stacking and testing operations.
NASA officials said the Mobile Launcher and newly installed hardware on Pad 39B and in the VAB should be ready NASA awards the contract to build a second SLS launch tower
While the workers Preparing to Launch the SLS in Kennedy NASA announced this week that Bechtel National Inc., a Virginia company, will build a second mobile starter to accommodate an updated, higher version of the space launch system.
Under a $ 383 million contract, Bechtel National will design, build, test and launch the second mobile launcher in a 44-month period from July 1st. The authorities assume that the new carrier missile tower, which will be erected directly in front of the vehicle assembly building at KSC, will be ready by early 2023.  Congress has provided funding for the second Mobile Launcher last year for a larger version of the SLS called Block 1B. The SLS block 1B will have a wider second stage, with four engines instead of the single engine flying first SLS missions.
Foster said NASA will give Bechtel National the flexibility to redesign some parts of the Mobile Launcher when they start working on the new model structure. The swivel arms will be built for pressurization, and NASA will develop a new umbilical arm to deliver propellants for the larger second stage of the SLS, referred to as Upper Stage Exploration.
The SLS Block 1B could debut as soon as the Artemis 3 is available starting in 2024 so that missions to the Moon can carry heavier payloads. Meanwhile, NASA plans to use commercial missiles to launch modules for the Gateway, a mini-station around the moon that will use the crews as lander and safe haven during the moon-landing expeditions.
NASA Spends $ 234 Million on Building the Original Mobile Vehicle According to reports from the government's Inspector General, which is configured for the Ares 1 rocket, the agency is expected to spend $ 753 million to upgrade the structure Accountability Office and NASA Budgetary Request for 2020.
Agency officials chose to use the Ares 1 tower for the space launch system because they were estimated to be less costly than changing one Launching Space Shuttle or Building a Brand New Structure
While the second Mobile Launcher will be larger than the first, NASA officials expect it to be cheaper.
"We've learned tons of lessons from it," he said. "ML-1 was not originally designed for SLS, so we had to make many structural changes that added weight.
" We basically had to weld parts to parts to stiffen them more. We do not have to do that with ML-2. We know what our loads are used for, we know what they were designed for. We hope that they will become easier, even if they get a bit bigger.
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