Starliner test flight slips two days
WASHINGTON — Boeing announced Dec. 3 that it’s delaying the uncrewed test flight of the company’s CST-100 Starliner commercial crew vehicle by two days because of a minor launch vehicle issue.
In an on-stage interview during a U.S. Chamber of Commerce commercial space conference here, Jim Chilton, senior vice president of the space and launch division of Boeing Defense, Space and Security, said Boeing had just received range approval to slip the Orbital Flight Test (OFT) launch two days to Dec. 19 at 6:59 a.m. Eastern.
“We had something come up over the weekend on purge ducting,” Chilton said, adding it was “a little off” and that the company decided to take the time to correct the problem and delay the launch.
United Launch Alliance, which provides the Atlas 5 rocket that will launch the Starliner, said in a later statement it involved an air supply duct. “Additional time was needed for the ULA and Boeing teams to complete an analysis of the issue, replace the duct and complete processing ahead of launch,” ULA stated. An industry source said the duct in particular was for the cavity in the launch vehicle adapter between the bottom of the Starliner and the top of the rocket’s Centaur upper stage.
The Orbital Flight Test is an uncrewed test flight of the vehicle, similar to the Demo-1 mission conducted by SpaceX’s Crew Dragon spacecraft in March. The flight will test the vehicle’s capabilities, including docking with the International Space Station, over the course of about a week. The spacecraft will then land, with White Sands Missile Range in New Mexico the primary landing site.
That mission will be followed by a crewed test flight, with NASA astronauts Michael Fincke and Nicole Mann as well as Boeing astronaut Chris Ferguson on board. NASA has not set a date for that launch, but it is not expected before spring 2020.
Launch of first Starliner orbital test flight slips to Dec. 19
The first launch of Boeing’s Starliner space capsule aboard a United Launch Alliance Atlas 5 rocket has been delayed to Dec. 19, officials announced Tuesday.
The liftoff of the Starliner’s Orbital Flight Test on top of was previously scheduled for Dec. 17 on a week-long demonstration mission to the International Space Station. The mission is a critical precursor for the Starliner’s first flight with astronauts, a milestone Boeing officials say is scheduled for mid-2020.
“During pre-launch processing of the Atlas 5, there was an issue with the rocket’s purge air supply duct,” ULA said in a statement Tuesday. “Additional time was needed for the ULA and Boeing teams to complete an analysis of the issue, replace the duct and complete processing ahead of launch.”
The purge air supply duct is a new feature on the Atlas 5 rocket inside the launch vehicle adapter cavity, according to ULA. The adapter structure connects the Atlas 5 rocket with the Starliner spacecraft.
The duct is a tube that carries air from the ground environmental control system into the launch vehicle adapter cavity for pre-launch cooling of avionics and the Starliner service module, ULA said.
Liftoff time Dec. 19 is scheduled for roughly 6:59 a.m. EDT (1159 GMT), approximately 10 minutes before sunrise. The exact launch time will be determined closer to launch day based on the latest tracking of the space station’s orbit.
“We continue to work closely with Boeing to ensure that the Starliner flies as soon as the spacecraft and launch vehicle are ready,” ULA said.
Boeing is developing the Starliner crew capsule under a $4.2 billion contract awarded by NASA in 2014. NASA has tapped Boeing and SpaceX to develop new human-rated spaceships to end U.S. reliance on Russian Soyuz crew ferry ships to transport astronauts to and from the space station.
ULA has assembled the Atlas 5 rocket over the last month inside the Vertical Integration Facility just south of pad 41. Technicians first stacked the Atlas first stage on its mobile launch platform inside the VIF, then added two strap-on solid rocket boosters Nov. 6 and Nov. 7. The Atlas 5’s dual-engine Centaur upper stage was hoisted atop the rocket Nov. 8, followed by a sequence of checkouts on the launcher before Boeing’s Starliner crew capsule arrived for installation on the launch vehicle Nov. 21.
The Atlas 5 will ride its mobile launch platform for the 1,800-foot journey to pad 41 Wednesday, where ULA has built a crew access tower and white room to allow astronauts to board the Starliner through its side hatch.
Two trackmobile railcars will power the journey on rails from the VIF to the launch mount at pad 41.
ULA, Boeing and NASA teams are gearing up for the Integrated Day-of-Launch Test, or IDOLT, exercise to practice launch day procedures ahead of the Starliner’s first space mission.
The Atlas 5 launch team has lengthened the countdown for Starliner missions to more than 11 hours from its standard duration of early seven hours. The extra time allows a “blue team” of specialists — analogous to the space shuttle-era closeout crew — to assist astronauts in boarding the Starliner spacecraft after the Atlas 5 is fueled with cryogenic propellants.
The test “will give us the opportunity to deploy the crew access arm and verify all the access tower and arm interfaces with the spacecraft,” said Caleb Weiss, ULA’s mission manager for the Starliner program. “We will fully tank the vehicle, and we will have people out there at the pad that will be simulating day launch operations, just like they will be for a real launch day.
“So they will be in the white room, they’ll open up the hatch of the Starliner,” Weiss said in an earlier interview with Spaceflight Now. “They will practice going in and out, loading cargo, configuring Starliner for flight. So it’ll be a really good end-to-end system checkout of all the launch vehicle and spacecraft systems working together, as well as the people who are executing the operations.”
Once the IDOLT exercise is complete, the rocket will return to the VIF for additional testing and preparation activities ahead of liftoff later this month.
NASA Engineers Break SLS Test Tank on Purpose to Test Extreme Limits
Engineers at NASA’s Marshall Space Flight Center in Huntsville, Alabama, on Dec. 5 deliberately pushed the world’s largest rocket fuel tank beyond its design limits to really understand its breaking point. The test version of the Space Launch System rocket’s liquid hydrogen tank withstood more than 260% of expected flight loads over five hours before engineers detected a buckling point, which then ruptured. Engineers concluded the test at approximately 11 p.m.
“We purposely took this tank to its extreme limits and broke it because pushing systems to the point of failure gives us additional data to help us build rockets intelligently,” said Neil Otte, chief engineer of the SLS Stages Office at Marshall. “We will be flying the Space Launch System for decades to come, and breaking the propellant tank today will help us safely and efficiently evolve the SLS rocket as our desired missions evolve.”
The test version of the tank aced earlier tests, withstanding forces expected at engine thrust levels planned for Artemis lunar missions, showing no signs of cracks, buckling or breaking. The test on Dec. 5 -- conducted using a combination of gaseous nitrogen for pressurization and hydraulics for loads -- pushed the tank to the limits by exposing it to higher forces that caused it to break as engineers predicted. Earlier tests at Marshall certified the tank for both the current version of the SLS -- called Block 1, which will use an upper stage called the Interim Cryogenic Propulsion Stage -- and the Block 1B version that will replace the ICPS with the more powerful Exploration Upper Stage.
“This final tank test marks the largest-ever controlled test-to-failure of a NASA rocket stage pressurized tank,” said Mike Nichols, Marshall’s lead test engineer for the tank. This data will benefit all aerospace companies designing rocket tanks.”
For all the tests, NASA and Boeing engineers simulated liftoff and flight stresses on a test version of the Space Launch System liquid hydrogen tank that is structurally identical to the flight tank. Throughout the tests in Marshall’s 215-foot-tall test stand, they used large hydraulic pistons to deliver millions of pounds of punishing compression, tension and bending forces on the robust test tank.
The test tank was fitted with thousands of sensors to measure stress, pressure and temperature, while high-speed cameras and microphones captured every moment to identify buckling or cracking in the cylindrical tank wall.
“The initial tank buckling failure occurred at the same relative location as predicted by the Boeing analysis team and initiated within 3% of the predicted failure load,” said Luke Denney, qualification test manager for Boeing’s Test & Evaluation Group. “The accuracy of these predictions against real life testing validates our structural models and provides high confidence in the tank design.”
Teams at Michoud are wrapping up functional testing of the assembled SLS core stage for the Artemis I mission and already are building the core stage for the Artemis II mission. The 212-foot-tall core stage is the largest, most complex rocket stage NASA has built since the Saturn V stages that powered the Apollo missions to the Moon.
“We are happy that NASA’s tests with the core stage structural test article will contribute not only to Space Launch System flights but also to the design of future rocket propellant tanks,” said Julie Bassler, manager of the SLS Stages Office.
SLS is the only rocket that can send Orion, astronauts and supplies to the Moon on a single mission. SLS, Orion and the Gateway in orbit around the Moon, are NASA’s backbone for deep space exploration and the Artemis program, which will send the first woman and next man to the lunar surface by 2024.