Miguel J. Rodriguez Carrillo/AFP through Getty Photographs
The primary crewed check flight of Boeing’s long-delayed Starliner spacecraft will not take off as deliberate Saturday, and will face an extended postponement as engineers consider a cussed leak of helium from the capsule’s propulsion system.
NASA introduced the newest delay within the Starliner check flight late Tuesday. Officers will take extra time to think about their choices for learn how to proceed with the mission after discovering the small helium leak on the spacecraft’s service module.
The house company didn’t describe what choices are on the desk, however sources mentioned they vary from flying the spacecraft “as is” with an intensive understanding of the leak and confidence it will not change into extra important in flight, to eradicating the capsule from its Atlas V rocket and taking it again to a hangar for repairs.
Theoretically, the previous possibility may allow a launch try as quickly as subsequent week. The latter different may delay the launch till at the least late summer time.
“The staff has been in conferences for 2 consecutive days, assessing flight rationale, system efficiency, and redundancy,” NASA mentioned in an announcement Tuesday evening. “There may be nonetheless ahead work in these areas, and the subsequent attainable launch alternative remains to be being mentioned. NASA will share extra particulars as soon as we’ve got a clearer path ahead.”
Delays are nothing new for the Starliner program, nevertheless it’s not but clear how this delay will evaluate to the spacecraft’s earlier setbacks.
Software program issues lower brief an unpiloted check flight in 2019, forcing Boeing to fly a second demonstration mission. Starliner was on the launch pad when pre-flight checkouts revealed caught valves within the spacecraft’s propulsion system in 2021. Boeing lastly flew Starliner on a round-trip mission to the house station in Could 2022. Issues about Starliner’s parachutes and flammable tape contained in the spacecraft’s crew cabin delayed the crewed check flight from final summer time till this yr.
Boeing goals to change into the second firm to fly astronauts to the house station beneath contract with NASA’s business crew program, following the beginning of SpaceX’s crew transportation service in 2020. Assuming a clean crewed check flight, NASA hopes to clear the Starliner spacecraft for six-month crew rotation flights to the house station starting subsequent yr.
Within the doghouse
Engineers first observed the helium leak throughout the the primary launch try for Starliner’s crewed check flight Could 6, however managers didn’t think about it important sufficient to cease the launch. In the end, a separate drawback with a stress regulation valve on the spacecraft’s United Launch Alliance (ULA) Atlas V rocket prompted officers to wash the launch try.
NASA astronauts Butch Wilmore and Suni Williams have been already strapped into their seats contained in the Starliner spacecraft on the launch pad at Cape Canaveral House Power Station, Florida, when officers ordered a halt to the Could 6 countdown. Wilmore and Williams returned to their properties in Houston to await the subsequent Starliner launch alternative.
ULA returned the Atlas V rocket to its hangar, the place technicians swapped out the defective valve in time for one more launch try Could 17. NASA and Boeing pushed the launch date again to Could 21, then to Could 25, as engineers assessed the helium leak. The Atlas V rocket and Starliner spacecraft stay inside ULA’s Vertical Integration Facility to attend for the subsequent launch alternative.
Boeing engineers traced the leak to a flange on a single response management system thruster in one in all 4 doghouse-shaped propulsion pods on the Starliner service module.
There are 28 response management system thrusters—primarily small rocket engines—on the Starliner service module. In orbit, these thrusters are used for minor course corrections and pointing the spacecraft within the correct path. The service module has two units of extra highly effective engines for bigger orbital changes and launch-abort maneuvers.
The spacecraft’s propulsion system is pressurized utilizing helium, an inert gasoline. The thrusters burn a mix of poisonous hydrazine and nitrogen tetroxide propellants. Helium is just not flamable, so a small leak is just not more likely to be a serious security problem on the bottom. Nevertheless, the system wants adequate helium gasoline to drive propellants from their inner storage tanks to Starliner’s thrusters.
In an announcement final week, NASA described the helium leak as “steady” and mentioned it could not pose a threat to the Starliner mission if it did not worsen. A Boeing spokesperson declined to offer Ars with any particulars concerning the helium leak price.
If NASA and Boeing resolve their considerations concerning the helium leak with out requiring prolonged repairs, the Worldwide House Station may accommodate the docking of Starliner by way of a part of July. After docking on the station, Wilmore and Williams will spend at the least eight days on the advanced earlier than undocking to move for a parachute-assisted, airbag-cushioned touchdown within the southwestern United States.
After July, the schedule will get messy.
The house station has a busy slate of a number of visiting crew and cargo automobiles in August, together with the arrival of a contemporary staff of astronauts on a SpaceX Dragon spacecraft, and the departure of an outgoing crew on one other Dragon. There could also be an extra window for Starliner to dock with the house station in late August or early September earlier than the launch of SpaceX’s subsequent cargo mission, which is able to occupy the docking port Starliner wants to make use of. The docking port opens up once more within the fall.
ULA additionally has different high-priority missions it want to launch from the identical pad wanted for the Starliner check flight. Later this summer time, ULA plans to launch US House Power’s last mission to make use of an Atlas V rocket. Then, ULA goals to launch the second demonstration flight of its new Vulcan Centaur rocket—the Atlas V’s substitute—as quickly as September.
