NASA’s Exploration Ground Systems team, including engineers, technicians and crane operators with contractor Jacobs, are practicing lifting and stacking operations with pathfinder segments of Northrup Grumman’s solid rocket boosters, which will provide extra thrust for NASA’s Space Launch System rocket. Practice took place in High Bay 4 of the Vehicle Assembly Building at the agency’s Kennedy Space Center in Florida.
”The pathfinder training has gone extremely well,” according to Michael McClure, Jacobs’ lead engineer for the Handling, Mechanical and Structures Engineering Group. “This is part of a series of practice exercises, which are providing great experience, especially for our new technicians, engineers, quality control personnel and crane operators.”
Stacking rehearsals help prepare the team for actual processing of launch hardware for Artemis missions. These specific pathfinder segments are inert, full-scale replicas of the actual solid rocket boosters, with the same weight (300,000 pounds) and center of gravity.
During launch hardware processing, the booster segments will be shipped by train to Kennedy from the Northrup Grumman facility in Utah. They will arrive at a processing facility to be configured for final processing, then move to the VAB, where the launch processing team will stack them vertically on the mobile launcher. After the boosters are stacked, the SLS Core Stage will be lowered onto the mobile launcher and will be mated to the boosters.
At launch, the five-segment, 17-story-tall twin boosters will provide 3.6 million pounds of thrust each at liftoff to help launch the SLS carrying Orion on Artemis I, its first uncrewed mission beyond the Moon.
NASA’s Pegasus barge, with the 212-foot-long Space Launch System (SLS) rocket core stage pathfinder secured inside, departed the Launch Complex 39 turn basin wharf at NASA’s Kennedy Space Center in Florida on Oct. 31, 2019.
The pathfinder is a full-scale mock-up of the rocket’s core stage. It was used by the Exploration Ground Systems Program and its contractor, Jacobs, to practice offloading, moving and stacking maneuvers inside the Vehicle Assembly Building using ground support equipment to train employees and certify all the equipment works properly. The pathfinder was at Kennedy for about a month.
The barge is carrying the pathfinder back to the agency’s Michoud Assembly Facility in Louisiana.
NASA’s Pegasus Barge arrived at the agency’s Kennedy Space Center in Florida on Sept. 27, carrying the 212-foot-long core stage pathfinder for the Space Launch System (SLS) rocket. Weighing in at 228,000 pounds, the pathfinder is a full-scale mock-up of the rocket’s core stage and will be used to validate ground support equipment and demonstrate it can be integrated with Kennedy facilities.
After arriving at the Launch Complex 39 turn basin wharf – a docking area initially used during the Space Shuttle Program that has been modified to accommodate SLS hardware deliveries – the pathfinder was moved into the Vehicle Assembly Building (VAB) on Sept. 30, where it will remain for testing for about one month.
While in the VAB, pathfinder will provide NASA’s Exploration Ground Systems (EGS) and contractor Jacobs with the opportunity to practice stacking maneuvers in the VAB’s High Bay 3 prior to the arrival of the SLS flight hardware that will be processed for the agency’s Artemis I mission.
“This will help ensure that all core stage engineers and technicians are trained and certified in preparation for the flight core stage processing,” said Jim Bolton, EGS core stage element operations manager at Kennedy. “It’s a very significant milestone that will demonstrate the capabilities and ability for KSC to receive, process and integrate that flight hardware.”
The core stage – the largest rocket stage in the world and the backbone of SLS – will provide the power necessary to send NASA’s Orion spacecraft beyond Earth’s orbit and to the Moon. Before it can be brought to Kennedy for processing, the core stage will undergo its first full test with all flight hardware, known as a green run, at the agency’s Stennis Space Center in Mississippi. Following this, Pegasus will make its return journey to Kennedy in 2020 – this time, delivering the SLS core stage for launch.
Even the toughest vehicles need regular maintenance to function at their best. Recently, William Vardaman and Pat Brown, both working under the Jacobs contracting team, performed engine maintenance on NASA’s crawler-transporter 2 in the crawler yard located in the agency’s Kennedy Space Center’s Launch Complex 39 area in Florida.
The massive, tracked vehicles are powered by large electrical power engines and two 16-cylinder American Locomotive Company (ALCO) engines. Vardaman and Brown, both mechanical technicians supporting the agency’s Test and Operations Support Contract, spent several days rebuilding the vehicle’s fuel pump assemblies on both ALCO engines. They also installed new oil pumps that will lubricate the ALCOs from the top down before they’re started, minimizing future wear.
This is one of two crawler-transporters that carried rockets and spacecraft, including the Apollo/Saturn V and space shuttle, from the Vehicle Assembly Building (VAB) to the launch pad. Now, they’re getting ready for NASA’s accelerated return to the Moon.
Crawler-transporter 2 has been modified and upgraded to carry the mobile launcher and NASA’s Space Launch System rocket, topped by the Orion spacecraft, for Exploration Mission-1, which will launch in 2020. The agency’s Exploration Ground Systems oversaw extensive upgrades to crawler-transporter 2, including new generators, gear assemblies, roller bearings and brakes, as well as the hydraulic jacking, equalization and leveling (JEL) cylinders that keep its carrying surface level.
Last fall, crawler-transporter 2 carried the newly completed mobile launcher from its construction site north of the VAB, out to Launch Pad 39B, then into the VAB, where the mobile launcher continues extensive testing. The crawler is gearing up for another move of the mobile launcher back to the pad later this spring for more testing.
Launch Abort System, or LAS, motors are being assembled and checked out at NASA’s Kennedy Space Center in Florida for an upcoming test for the Orion spacecraft designed to send astronauts on trips to the Moon, and support human exploration to Mars.
Orion is designed to launch atop the agency’s Space Launch System (SLS) rocket that will take astronauts into deep space. Before flying astronauts, the Ascent Abort-2 (AA-2) flight test will help verify that the LAS can pull astronauts to safety in the event of a problem during launch.
The crew escape system will be attached to the top of the spacecraft.
According to Carlos Garcia of Orion Production Operations at Kennedy there are three motors on the LAS- the abort, attitude control and jettison motors. The abort motor can propel the crew module away from the rocket in milliseconds should there be an issue with SLS on the pad or during launch. The attitude control motor would steer the spacecraft during the maneuver. The jettison motor will pull the LAS away from the crew module, allowing Orion’s parachutes to deploy with the spacecraft safely landing in the ocean.
The abort and jettison motors for the test arrived on Aug. 27 and Sept. 10, 2018 respectively, and the attitude control motor was delivered Dec. 15.
“As the motor segments come in, we align and mate them to the motor truss assembly,” Garcia said. “We’re working on the electrical connections now.”
“Once the LAS assembly and checkout are complete, we’ll do a soft mate to the Orion crew module mock-up,” Garcia said. “That test will help us make sure everything is working as intended.”
For AA-2, a test version of Orion equipped with 284 sensors will launch atop a booster provided by Northrop Grumman from Space Launch Complex (SLC) 46 at Cape Canaveral Air Force Station. The test booster is being processed in the space center’s Vehicle Assembly Building and later will be transported to SLC 46.
“After the LAS is mated to Orion, the combination will be moved to the Cape for mating to the booster,” Garcia said.
Targeted for May 2019, AA-2 will test an LAS abort under the highest aerodynamic loads it would experience in flight. The booster will accelerate to 31,000 feet, traveling at more than 1,000 miles an hour. The LAS abort motor then will ignite, pulling the crew module away from the booster.
The jettison motor separates the LAS from the crew module. The AA-2 test will conclude as data recorders are jettisoned for retrieval in the Atlantic Ocean.
The third and final aeroshell, at left, for Orion’s Launch Abort System (LAS) is in High Bay 4 of the Vehicle Assembly Building on July 12, 2018, at NASA’s Kennedy Space Center in Florida after its arrival from EMF Inc. on nearby Merritt Island. In the photo above, technicians prepare the aeroshell to be lifted off of the flatbed truck and transferred to slats. All three aeroshells will be stacked and prepared for a full-stress test of the LAS, called Ascent Abort-2 (AA-2) flight test, scheduled for April 2019.
During the test, a booster will launch from Space Launch Complex 46 at Cape Canaveral Air Force Station carrying a fully functional LAS and a 22,000-pound Orion test vehicle to an altitude of 31,000 feet and traveling at more than 1,000 miles per hour. The test will verify the LAS can steer the crew module and astronauts aboard to safety in the event of an issue with the Space Launch System (SLS) rocket when the spacecraft is under the highest aerodynamic loads it will experience during a rapid climb into space.
NASA’s Orion is being prepared for its first integrated uncrewed flight atop the SLS on Exploration Mission-1.
Nearly the last of several large connection lines, called umbilicals, was installed on the mobile launcher at NASA’s Kennedy Space Center in Florida. The umbilical was lifted by crane and attached high on the tower of the mobile launcher at about the 240-foot level, bringing the steel structure one step closer to supporting processing and launch of NASA’s Orion spacecraft and Space Launch System (SLS) rocket. The launcher is designed to support the assembly, testing, check out and servicing of the rocket, as well as transfer it to the pad and provide the platform from which it will launch.
This particular umbilical will supply propellants, environmental control systems, pneumatics and electrical connections to the interim cryogenic propulsion stage (ICPS) of the SLS rocket and will swing away before launch. The umbilical also will provide hazardous gas leak detection while the rocket is on the pad. The ICPS is located between the core stage of the rocket and the Orion capsule, and will provide propulsion for Orion while in space and give the spacecraft the big push needed to fly beyond the moon.
To install the umbilical, construction workers with JP Donovan prepared the rigging lines and attached the umbilical to a large crane. The ICPS umbilical was slowly lifted up and bolted to the mobile launcher. The entire process took about four hours.
With the umbilical in place, workers will install additional equipment on the tower, as well as electrical wiring, environmental control system tubing, hydraulics and other commodities will be routed to the umbilical arm before testing. Tests of the swing arm also will be performed as part of the verification and validation process.
Exploration Ground Systems is overseeing installation of the launch umbilicals and launch accessories on the mobile launcher to prepare for the first integrated test flight of Orion atop the SLS on Exploration Mission-1. A pair of tail service mast umbilicals are slated for installation later this year and will be the last of the twenty umbilicals and launch accessories to be installed on the mobile launcher. With this test flight, NASA is preparing for missions to send astronauts to deep space destinations, including the Moon, Mars and beyond.
When astronauts depart for missions to deep space, they will cross the Crew Access Arm about 300 feet above the ground to board their spacecraft. The access arm was delivered to NASA’s Kennedy Space Center in Florida on Oct. 17, 2017, to install on the mobile launcher in preparation for the first flight of the Space Launch System rocket, or SLS, and the Orion spacecraft.
The SLS will be the largest rocket in the world and will be stacked with Orion inside the historic Vehicle Assembly Building, or VAB, on the mobile launcher and rolled out to the pad prior to launch. The access arm will be one of 11 connection points to the rocket and spacecraft from the tower on the mobile launcher. After technicians install the arm, the mobile launcher will be rolled into the VAB for validation and verification tests.
For the first launch without crew, the access arm will provide a bridge to Orion for personnel and equipment entering the spacecraft during processing and prelaunch integrated testing while in the VAB and at the launch site. The arm is made up of two major components: the truss assembly and the environmental enclosure, or the white room. The arm will provide entry and emergency egress for astronauts and technicians into the Orion spacecraft. On future human missions, astronauts outfitted with newly designed space suits will enter the white room, where they will be assisted by technicians into the spacecraft for launch. The arm will retract before launch, and the other connections will release at liftoff, allowing the rocket and spacecraft to safely clear the launch pad.
Engineers lifted and installed a third umbilical on the mobile launcher at NASA’s Kennedy Space Center in Florida for a fit check. The tower on the mobile launcher will be equipped with several connections or launch umbilicals like this one. After the fit check was completed, the umbilical was lowered down and will be installed permanently at a later date.
The umbilicals will provide power, communications, coolant and fuel. They will be used to connect the mobile launcher to the agency’s Space Launch System (made up of the core stage, twin solid rocket boosters, and the interim cryogenic propulsion stage) and the Orion spacecraft mounted on top of SLS.
An area on the SLS between the liquid hydrogen and liquid oxygen tanks is known as the core stage inter-tank. The core-stage inter-tank umbilical is the third in a series of five new umbilicals for the mobile launcher. Its main function is to vent excess gaseous hydrogen from the rocket’s core stage. This umbilical also will provide conditioned air, pressurized gases, and power and data connection to the core stage.
The Orion service module umbilical and the core stage forward skirt umbilical were previously installed on the tower. The service module umbilical will connect from the mobile launch tower to the Orion service module. Prior to launch, the umbilical will transfer liquid coolant for the electronics and purge air/gaseous nitrogen for environmental control. The SLS core stage forward skirt is near the top of the core stage, and the forward skirt umbilical provides connections and conditioned air/gaseous nitrogen to the core stage of the rocket. All these umbilicals will swing away from the rocket and spacecraft just before launch.
Several other umbilicals were previously installed on the mobile launcher. These include two aft skirt purge umbilicals, which will connect to the SLS rocket at the bottom outer edge of each booster and provide electrical power and data connections, remove hazardous gases, and maintain the right temperature range with a nitrogen purge in the boosters until SLS lifts off from the launch pad.
New service platforms for NASA’s Space Launch System (SLS) booster engines arrived at the agency’s Kennedy Space Center in Florida. The platforms were transported on two flatbed trucks from fabricator Met-Con Inc. in Cocoa, Florida. They were offloaded and stored inside the Vehicle Assembly Building (VAB).
The platforms will be used for processing and checkout of the engines for the SLS’ twin five-segment solid rocket boosters for Exploration Mission-1 (EM-1). The boosters, in combination with the rocket’s four RS-25 engines, will produce more than 8 million pounds of thrust at liftoff.
The first SLS mission, EM-1, will launch an uncrewed Orion spacecraft to a stable orbit beyond the Moon and bring it back to Earth for a splashdown in the Pacific Ocean. The mission will demonstrate the integrated system performance of the rocket, Orion spacecraft and ground support teams prior to a crewed flight.