Names | Boe-CFT[1] |
---|---|
Mission type | Test flight |
Operator | Boeing Defense, Space & Security |
COSPAR ID | 2024-109A |
SATCAT no. | 59968 |
Mission duration | 1 day, 21 hours and 59 minutes (in progress) ~8 days (planned) |
Spacecraft properties | |
Spacecraft | Boeing Starliner Calypso |
Spacecraft type | Boeing Starliner |
Manufacturer | Boeing Defense, Space & Security |
Crew | |
Crew size | 2 |
Members | |
Start of mission | |
Launch date | 5 June 2024, 14:52:15 UTC |
Rocket | Atlas V N22[a] |
Launch site | Cape Canaveral, SLC-41 |
Contractor | United Launch Alliance[b] |
End of mission | |
Landing date | 14 June 2024 (planned) |
Landing site | TBD[c] |
Orbital parameters | |
Reference system | Geocentric orbit |
Regime | Low Earth orbit |
Inclination | 51.66° |
Docking with ISS | |
Docking port | Harmony forward |
Docking date | 6 June 2024, 17:34 UTC |
Undocking date | TBD |
Time docked | 19 hours and 17 minutes (in progress) |
Boeing Crew Flight Test mission patch Williams (left) and Wilmore (Right) |
Boeing Crew Flight Test (Boe-CFT) is the first crewed mission of the Boeing Starliner and the third orbital flight test of the Starliner overall after the two uncrewed orbital flight tests, Boe-OFT and Boe-OFT 2 in 2019 and 2022.
The first crewed flight test was initially planned to occur in 2017.[2] Various delays pushed the launch of the CFT mission to no earlier than 21 July 2023.[3] Boeing announced in August 2023 that it would be delayed to no earlier than March 2024 due to issues with the parachute system and wiring harnesses and further investigations.[4]
The mission entails flying a crew of two NASA astronauts, Barry E. Wilmore and Sunita Williams, to the International Space Station for a one-week test flight and then returning the crew via a ground landing in the American Southwest. The spacecraft was integrated with the Atlas launch vehicle on 16 April 2024 in preparation for launch.[5]
The flight was scheduled for liftoff at 2:34 UTC on 7 May 2024, but was scrubbed about two hours before liftoff due to an oxygen valve problem on the United Launch Alliance's (ULA) Atlas V.[b][6][7] After the initial scrub, the launch was repeatedly delayed due to a helium leak in the Starliner service module.[8]
The second launch attempt was on 1 June at 16:25 UTC, but was scrubbed 3 minutes, 50 seconds before liftoff when the ground launch sequencer computer registered a loss of redundancy due to a faulty power supply. The third launch attempt, on 5 June at 14:52 UTC, was successful.
CFT is the second mission for the Starliner Calypso capsule, which was first used on the first Orbital Flight Test. NASA announced that Boeing prepared to reassemble the vehicle for flight, following multiple checkouts, for the CFT mission in August 2020, and that new parachutes and airbags would be fitted. The CFT capsule's docking system was modified to accommodate the new re-entry cover that debuted on the OFT 2 test flight.[9]
Nicole Aunapu Mann was initially assigned to this mission, which would have made her the first woman to fly on the maiden crewed flight of an orbital spacecraft, but was subsequently reassigned to the SpaceX Crew-5 mission as the first female commander of a NASA Commercial Crew Program launch.[10] For medical reasons, Eric Boe, who was originally assigned to the mission in August 2018 as the pilot, was replaced by Michael Fincke on 22 January 2019. Boe will replace Fincke as the assistant to the chief for commercial crew in the astronaut office at NASA's Johnson Space Center.[11] Boeing astronaut Chris Ferguson was originally assigned to the flight as commander, but he was replaced by NASA astronaut Barry E. Wilmore on 7 October 2020. Ferguson cited family reasons for the replacement.[12] Matthew Dominick replaced him on the backup crew.[13]
On 18 April 2022, NASA said that it had not finalized which of the cadre of Starliner astronauts, including Barry E. Wilmore, Michael Fincke, and Sunita Williams, will fly on this mission or the first operational Starliner mission.[14] On 16 June 2022, NASA confirmed that this CFT mission will be a two-person flight test, consisting of Wilmore and Williams; Fincke is to train as the backup spacecraft test pilot and remains eligible for assignment to a future mission.[15] Williams is the first woman to fly on a maiden crewed flight of an orbital spacecraft type (Judith Resnik was the first female crew member on the maiden flight of an orbital spacecraft, the Space Shuttle Discovery).
Position | Crew member | |
---|---|---|
Spacecraft commander | Barry E. Wilmore, NASA Third spaceflight | |
Pilot | Sunita Williams, NASA Third spaceflight |
Position | Crew member | |
---|---|---|
Spacecraft commander | Michael Fincke, NASA |
The third launch of the Atlas V N22[a] variant will launch Starliner with a crew of two. The vehicle will dock with the International Space Station, and return to Earth for a ground landing in the southwestern United States.
Boe-CFT is the first launch of a crewed spacecraft by an Atlas V launch vehicle. In addition, the mission is the first launch of a crewed spacecraft utilizing a member of the Atlas family of launch vehicles since Mercury-Atlas 9 flown by Gordon Cooper in May 1963[16] and the first launch of a crewed spacecraft from Cape Canaveral Space Force Station since that of Apollo 7 in October 1968.[16]
A short-duration mission with two astronaut test pilots is sufficient to meet all NASA and Boeing test objectives for CFT, which include demonstrating Starliner's ability to safely fly operational crewed missions to and from the space station. However, to protect against unforeseen events aboard the station, NASA has added the flexibility to extend the duration of the CFT docking for up to six months.[15]
The Starliner will make a ground landing, a first for a crewed capsule mission launched from the United States. After reentering the atmosphere, three parachutes will be deployed, slowing the capsule to approximately 4 miles per hour (350 ft/min; 1.8 m/s). Before reaching the ground, six airbags will deploy to cushion the landing. There are four primary landing locations, including two sites inside the White Sands Missile Range in New Mexico, the Willcox Playa in Arizona and the Dugway Proving Ground in Utah. Edwards Air Force Base in California serves as a contingency landing location.[17]
In 2023, following the discovery of a technical issue with the spacecraft's parachute system and a flammability concern on the spacecraft's wiring, CFT was delayed to no earlier than March 2024.[18] In November 2023, NASA announced that the mission was on track for an April 2024 launch, with most of the flammable material removed from the spacecraft and a drop-test of the redesigned parachute system planned for January 2024.[19] This test was successful, allowing NASA and Boeing to proceed into launch preparations.[20] In February 2024, the Atlas V rocket was moved into ULA's Vertical Integration Facility at Space Launch Complex-41, starting preparations for stacking ahead of the launch.[21] In March 2024, the launch was rescheduled from April 22 to early May due to scheduling conflicts on the ISS,[22] with a launch date of May 6 announced in early April.[23] Work on the Starliner spacecraft inside Boeing's production facility was completed on April 15, and the spacecraft was moved to the launch pad and stacked on top the Atlas V rocket the following day.[24][25][26] The crew arrived at Kennedy Space Center on April 25,[27] and on the same day the mission concluded its Flight Test Readiness Review, officially approving the mission to proceed.[28] On May 2, the SpaceX Crew-8 Dragon spacecraft relocated from the forward port of the ISS Harmony module to the zenith port, to make room for the CFT mission, which is only approved to dock on the forward port.[29] Following the completion of ULA's Launch Readiness Review, the Atlas V rocket rolled to its launch pad on May 4.[30]
The first attempt to launch CFT, on May 6, was scrubbed around 2 hours before launch due to a problem with an oxygen valve on the rocket's Centaur upper stage. While this problem had been seen in previous Atlas V flights and could be resolved simply by closing and reopening the valve, new flight rules prohibited doing so with crew on board, which forced the decision to scrub the launch.[31][32] The next day, the launch team determined that this faulty valve would need to be replaced, with the rocket having to be rolled back to its Vertical Integration Facility, delaying the launch to May 17.[33][34] Meanwhile, in an unrelated issue, NASA and Boeing discovered a small helium leak on Starliner's propulsion system, which delayed the launch further to allow the teams to assess the situation.[35] On May 24, following several days of analysis, NASA and Boeing announced plans to launch CFT on June 1 without repairing the helium leak, determining that the spacecraft was safe to fly even if the leak rate worsened by many times. This review also uncovered a "design vulnerability" in the propulsion system that could prevent the spacecraft from completing a deorbit burn in a very remote failure mode; engineers then devised a new reentry mode to employ should this failure mode occur.[36][37] Astronauts Butch Wilmore and Suni Williams, after returning to Houston following the previous scrub, flew back to Kennedy Space Center on May 28. On May 29, during a Delta-Agency Flight Test Readiness Review, teams from NASA, Boeing, and ULA confirmed readiness for a June 1 launch.[38][39][40]
The second launch attempt, on June 1, was scrubbed 3 minutes and 50 seconds before liftoff after an automatic hold triggered after one of three redundant ground computers gave slower than normal readings.[41][42] The issue was pinned down on a single faulty power supply unit connected to that computer. On June 2, an ULA team replaced the computer chassis containing this power supply and verified that the new hardware was performing normally. The launch was rescheduled to the next available opportunity on June 5.[43]
CFT successfully lifted off on the Atlas V rocket on its third launch attempt, on June 5 at 10:52 a.m EDT. The mission was launched from ULA's SLC-41 launch site at Cape Canaveral Space Force Station, Florida, and was Atlas V's 100th flight. The rocket flew in the N22 configuration, with no payload fairing, two GEM 63 solid rocket boosters, and two RL10A-4-2 engines on the Centaur upper stage. The solid rocket boosters separated from the rocket 2 minutes and 20 seconds after liftoff. The core stage continued firing until 4 minutes and 28 seconds after launch and was separated shortly thereafter. The Centaur upper stage then began firing until 11 minutes and 52 seconds after launch. The Starliner spacecraft separated from the upper stage about 15 minutes after liftoff. To maximize safety, it was placed in a sub-orbital trajectory by the rocket, and used its own thrusters to enter orbit about 31 minutes after launch.[44][45]
Attempt | Planned | Result | Turnaround | Reason | Decision point | Weather go (%) | Notes |
---|---|---|---|---|---|---|---|
1 | 6 May 2024, 10:34:00 pm | Scrubbed | — | Centaur LOX valve issue | 6 May 2024, 8:32 pm (T-02:01:30) | 95 | |
2 | 1 Jun 2024, 12:25:40 pm | Scrubbed | 25 days, 13 hours, 52 minutes | Ground launch sequencer computer fault | 1 Jun 2024, 12:22 pm (T-00:03:35) | 90 | |
3 | 5 Jun 2024, 10:52:15 am | Success | 3 days, 22 hours, 27 minutes | 90 |
Time | Event |
---|---|
L−6:00:00 | Atlas V cryo load |
L−4:00:00 | Atlas V cryo load complete / stable configuration |
L−4:30:00 | Crew suit-up begins |
L−4:04:00 | T-4 minute hold begins |
L−3:20:00 | Crew suit-up complete / departs for launch pad |
L−3:10:00 | Crew Module preps begin |
L−2:50:00 | Crew arrives for insertion |
L−1:20:00 | Hatch closure complete |
L−0:50:00 | Cabin leak checks / cabin pressurization complete |
L−0:35:00 | Crew space to ground communication checks |
L−0:22:00 | Flight Director Poll: Go for terminal count |
L−0:20:00 | Crew visors configured for launch |
L−0:18:00 | Starliner poll for terminal count |
L−0:18:00 | Starliner to internal power |
L−0:11:00 | Crew access arm retracted |
L−0:07:00 | Atlas V launch vehicle poll for terminal count |
L−0:07:00 | Starliner configured for terminal count |
L−0:05:00 | Starliner configured for ascent |
L−0:04:00 | T-4 minute hold releases |
L−0:00:02.7 | RD-180 engine ignition |
L+0:00:01.1 | Liftoff (thrust to weight > 1) |
L+0:00:06.0 | Begin pitch/yaw maneuver |
L+0:01:01.7 | Maximum dynamic pressure |
L+0:01:05.3 | Mach 1 |
L+0:02:20.4 | SRB jettison |
L+0:04:28.9 | Atlas Booster Engine Cutoff (BECO) |
L+0:04:34.9 | Atlas Centaur separation |
L+0:04:40.9 | Ascent cover jettison |
L+0:04:44.9 | Centaur First Main Engine Start (MES-1) |
L+0:05:04.9 | Aeroskirt jettison |
L+0:11:55.4 | Centaur First Main Engine Cutoff (MECO-1) |
L+0:14:55.4 | Starliner Separation |
In the hours after getting into orbit, the crew performed a number of manual maneuvering exercises, including pointing the antenna towards the TDRSS communications satellites, pointing the solar panels towards the sun, manually using the star tracker, manually braking and accelerating the spacecraft to perform orbital maneuvers, and manually orienting the spacecraft for reentry. Although the Starliner spacecraft is designed to operate autonomously and these capabilities are not required in a nominal mission, these tests showed that the crew can successfully take over many functions of the craft during an emergency.[48]
Late June 5, just before the crew's sleep time, flight controllers on the ground detected two additional helium leaks in different parts of Starliner's propulsion system, in addition to the one that was already known previous to the flight. To manage these leaks, flight controllers temporarily closed the two helium manifolds associated with the new leaks, which had the effect of disabling 6 of the spacecraft's 28 reaction control system thrusters. The leaks were described as small and the spacecraft still had plenty of excess helium to complete its mission, so managers gave permission to proceed with docking operations. The helium manifolds were reopened during rendezvous and docking, and were subsequently closed once the spacecraft docked, as is standard procedure. A fourth leak, smaller than the other three, was detected after docking. The cause of the helium leaks is not yet known, but the fact that four separate leaks appeared is evidence that this might be a systemic problem with the propulsion system, contrary to expectations from NASA and Boeing managers prior to the mission that the first helium leak was an isolated issue caused by one defective seal.[49][50][51][52]
As Starliner approached the ISS, another problem appeared when five reaction control system thrusters were deactivated during flight. Mission teams managed to bring back four of the thrusters by doing a series of resets and hot-fire tests on them, during which the crew manually held the spacecraft just outside the station's 200-meter keep out zone. After verifying that the thrusters were operating normally, Starliner was given permission to dock with the station. The problem with the thrusters was similar to what happened during the uncrewed Orbital Flight Test 2 mission in 2022, when thrusters in the same location in the spacecraft were deactivated during approach. Mission managers believe the failure of the thrusters could be related to input data being outside some predetermined limits, rather than being a software or hardware problem, although the exact cause is unknown.[53][50][52]
Starliner successfully docked to the forward port of the Harmony module on the ISS on June 6 at 1:34 p.m. EDT, nearly 27 hours after launch. Docking was delayed by over an hour due to the problems with the spacecraft's reaction control thrusters.[50] Astronauts Butch Wilmore and Suni Williams entered the station at 3:45 p.m. EDT.[54]