Starship flight test 3 explained

Starship flight test 3
Mission Type:Flight test
Mission Duration:
1 hour, 4 minutes, 39 seconds (planned)
Orbits Completed:<1
Operator:SpaceX
Spacecraft:Starship Ship 28
Spacecraft Type:Starship
Manufacturer:SpaceX
Launch Date:UTC (8:25amCDT)
Launch Rocket:Super Heavy (B10)
Launch Site:Starbase, OLM-A
Destroyed:UTC (9:14:35amCDT)
Orbit Regime:Suborbital (achieved)[1]
Transatmospheric Earth orbit (planned)
Orbit Apoapsis: (achieved)
(planned)[2]
Orbit Periapsis:-50 km (achieved)
(planned)
Orbit Inclination:26.5°
Insignia:Starship flight test 3 patch.jpg
Insignia Caption:Mission patch
Programme:SpaceX Starship flight tests
Previous Mission:Flight 2
Next Mission:Flight 4

Starship flight test 3 was the third flight test of the SpaceX Starship launch vehicle. SpaceX performed the flight test on March 14, 2024.[3]

Starship successfully completed a full-duration second stage burn, reaching the intended orbital velocity for the first time, but broke up during re-entry in the atmosphere.[4] [5] [6]

Background

Changes from the previous flight

After the second flight test in November 2023 ended in the destruction of both the Super Heavy booster and the Starship spacecraft, 17 significant changes were made to the vehicles, including upgrading the ship to an electric thrust vector control (TVC) system[7] (the booster had been upgraded for the second flight test[8]) and delaying the vent of liquid oxygen (LOX) to after Starship engine cutoff (SECO).

SpaceX upgraded the orbital tank farm with additional subcoolers and pumps to increase the propellant flow rate. In addition, two water tanks were removed and scrapped. Steel plates have been added to concrete at the base of the launch tower due to erosion from the engines. A concrete wall has replaced the HESCO barriers previously protecting the tank farm.[9]

Development prior to launch

Testing of the Flight 3 vehicles began just under a month after second flight test,[10] [11] with S28 and B10 undergoing their individual static fire tests in late December 2023.[12] [13] The FAA closed its mishap investigation of the second flight test on February 26, 2024. In the mishap report, SpaceX identified 17 corrective actions, of which ten were for the Starship upper stage and seven for the Super Heavy booster.[14] Booster 10 and S28 conducted a wet dress rehearsal on March 3, 2024.[15] On March 5, 2024, SpaceX announced that they were targeting a launch date of March 14, 2024, pending regulatory approval.[16] [17] On March 13, 2024, the FAA granted the launch license for this flight, the third flight test.[18]

Flight profile

Starship flight test 3 launched from the SpaceX Starbase facility along the South Texas coast around 8:25 CDT. As with the second flight test, ignition of all 33 booster engines and stage separation were both successful.[19] B10 conducted a boostback burn. However, 6 engines began shutting down unexpectedly causing a premature boostback shutdown; the planned landing in the Gulf of Mexico was not successful due to the same six engines that failed before being disabled leaving seven engines commanded to startup with two successfully reaching ignition. Following the failures, SpaceX reported that the booster was destroyed at an estimated altitude of approximately . The cause of these failures was determined by SpaceX to be filter blockage of liquid oxygen to the engines. A similar problem occurred in the second flight test, leading Booster 10 to get upgraded filtering.[20]

The Starship spacecraft itself reached space and the intended orbital velocity. It then conducted several tests after engine cutoff, including a successful propellant transfer demo and payload dispenser test. It attempted to re-enter the atmosphere over the Indian Ocean, and at an altitude of around 65 km, all telemetry from Ship 28 stopped, indicating a loss of the vehicle.[21] [22] According to SpaceX, S28 was experiencing excessive roll rates causing it to have an "off-nominal entry". This was caused by clogging of the valves responsible for roll control on Starship.[23]

Mission timeline[24] !Time!Event!March 14, 2024
−01:15:00SpaceX Flight Director conducts a poll and verifies go for propellant loading
−00:53:00Starship oxidizer loading (liquid oxygen) underway
−00:51:00Starship fuel loading (liquid methane) underway
−00:42:00Super Heavy oxidizer loading (liquid oxygen) underway
−00:41:00Super Heavy fuel loading (liquid methane) underway
−00:19:40Booster engine chill
−00:03:30Booster propellant load complete
−00:02:50Ship propellant load complete
−00:00:30SpaceX flight director verifies GO for launch
−00:00:10Flame deflector activation
−00:00:03Booster engine ignition
00:00:02Liftoff
00:00:52Max q (moment of peak mechanical stress on the rocket)
00:02:42Booster Main Engine Cut Off (MECO)
00:02:44Starship engine ignition and stage separation (hot-staging)
00:02:55Booster boostback burn startup
00:03:50Booster boostback burn shutdown
00:06:36Booster is transonic
00:06:46Booster landing burn startup
00:07:04Booster landing burn shutdown
00:08:35Starship engine cutoff (SECO)
00:11:56Payload door open
00:24:31Propellant transfer demo
00:28:21Payload door close
00:40:46Raptor in-space relight demo
00:49:05Starship entry
01:02:16Starship is transonic
01:03:04Starship is subsonic
01:04:39Starship splashdown

Aftermath

After the launch, SpaceX confirmed that Super Heavy was destroyed at 462 m above sea level over the Gulf of Mexico.[3] The status of the payload door test became one of the focuses of unofficial interpretations of the flight in YouTube and news articles, due to a perceived issue seen from the flight video concerning the payload door. SpaceX's account of the launch states that the payload test had been a success.[20]

Gwynne Shotwell, president and chief operating officer of SpaceX, said the company was still investigating the data and what went wrong in the third flight test, but that the fourth flight test could launch soon, possibly by early May.[25]

NASA chief Bill Nelson praised SpaceX for "a successful test flight". He also stated, "Today we are making great strides through Artemis to return humanity to the Moon - then look onward to Mars." SpaceX founder and CEO Elon Musk also praised the team and stated "Starship will take humanity to Mars."[26]

On March 14, 2024, the FAA declared that a mishap had occurred involving both the upper stage and booster, triggering the start of a SpaceX-led investigation overseen by the FAA.[27] The agency's associate administrator for commercial space transportation, Kelvin Coleman, said on March 18 that he did not anticipate any major issues that could delay the investigation. Additionally, there was talk for the FAA to begin issuing a "portfolio of launches", authorizing multiple launches rather than a single launch at a time, as part of a broader effort to streamline the launch license process in response to criticism from SpaceX and Congress that the FAA was moving too slow on approving them.[28] The next launch license will likely require modification, but Coleman said the FAA may be able to first complete a public safety determination, finding that there were no flaws in critical safety systems on the March launch that would have endangered the safety of the uninvolved public. If so, “that would decouple the mishap investigation from the license modification, and that means that we could get the license modification done while the mishap investigation is ongoing.”[29] However, both are still needed in order for a launch license to be granted.[30]

On April 5, SpaceX requested that the FAA agree that the third flight test mishap did not present a public safety issue.[31] On May 11, SpaceX founder and CEO Elon Musk stated that the fourth Starship launch could occur in 3-5 weeks, bringing the date forward to early-mid June. The FAA investigation and launch license remained pending.[32] On May 17, the FAA made a statement that if the FAA agrees no public safety issues were involved in the mishap, SpaceX may return to flight while the third flight test investigation remains open, provided all other license requirements are met.[33] This statement does not constitute SpaceX being granted a Launch License.

On May 24, SpaceX released a blog post stating the results from flight 3. According to SpaceX, during the boostback burn, 6 engines began to shut down, causing an early boostback shutdown. The vehicle prevented these engines from performing the landing burn, leaving only 7 engines. 2 of the engines were able to successfully ignite. The vehicle had lower than expected thrust, and it was lost at an altitude of 462 meters. The main likely cause of the boostback shutdown was due to filter blockage in the liquid oxygen intake, leading to loss of pressure in the oxygen turbopumps. According to SpaceX, several minutes after the ship engine cutoff (SECO), the valves responsible for the roll control thrusters were clogged. This precluded the in flight raptor relight test. Due to the unplanned roll, the ship experienced much higher heat loads in both unprotected and tiled sections.

In order to mitigate these issues, SpaceX has implemented hardware changes to the booster liquid oxygen tank to improve propellant filtration. SpaceX has also added more roll control thrusters on the ship for redundancy. Additionally, hardware and software changes were implemented to improve Raptor startup reliability.[20]

See also

Notes and References

  1. Web site: Jonathan's Space Report No. 831 . McDowell . Jonathan . Jonathan McDowell . March 14, 2024 . . March 14, 2024 . March 29, 2019 . https://web.archive.org/web/20190329001529/https://planet4589.org/space/jsr/latest.html . live .
  2. Web site: Narrative Description: STA Application No. 2224-EX-ST-2023 . November 8, 2023 . . March 14, 2024 .
  3. Web site: Starship's Third Flight Test . March 14, 2024 . SpaceX . March 6, 2024 . https://web.archive.org/web/20240306183144/https://www.spacex.com/launches/mission/?missionId=starship-flight-3 . live .
  4. News: Chang . Kenneth . March 14, 2024 . SpaceX Blazes Forward With Latest Starship Launch . live . https://archive.today/20240314171029/https://www.nytimes.com/2024/03/14/science/spacex-starship-rocket-launch.html . March 14, 2024 . March 14, 2024 . The New York Times.
  5. Web site: Sheetz . Michael . March 14, 2024 . SpaceX's Starship notches major flight test milestones, breaks up over Indian Ocean in final moments . March 14, 2024 . CNBC . en . March 14, 2024 . https://web.archive.org/web/20240314192525/https://www.cnbc.com/2024/03/14/spacex-starship-rocket-third-test-flight-launch.html . live .
  6. Web site: March 15, 2024 . SpaceX's Starship destroyed on return to Earth at end of third test flight . March 15, 2024 . Theguardian . en-US . March 15, 2024 . https://web.archive.org/web/20240315062953/https://www.theguardian.com/science/2024/mar/14/spacex-launches-third-starship-test-flight . live .
  7. Web site: SpaceX - Updates . February 26, 2024 . . March 13, 2024 . September 13, 2023 . https://web.archive.org/web/20230913205323/https://www.spacex.com/updates/ . live .
  8. Web site: SpaceX poised for 'mid-November' launch of second Starship test flight . Robinson-Smith . Will . November 4, 2023 . Spaceflight Now . March 13, 2024 . January 24, 2024 . https://web.archive.org/web/20240124024755/https://spaceflightnow.com/2023/11/04/spacex-poised-for-mid-november-of-second-starship-test-launch/ . live .
  9. Web site: Wet dress rehearsal on the horizon for Starship's third flight . Weber . Ryan . January 25, 2024 . . March 13, 2024 . February 4, 2024 . https://web.archive.org/web/20240204014937/https://www.nasaspaceflight.com/2024/01/wdr-horizon-flight-3/ . live .
  10. .
  11. Web site: Alejandro Alcantarilla . Romera . December 18, 2023 . alexphysics13/status/1736722892878971139 . live . https://web.archive.org/web/20231218140744/https://twitter.com/alexphysics13/status/1736722892878971139 . December 18, 2023 . December 18, 2023.
  12. .
  13. SpaceX Dual Static fire of Booster 10 and Starship 28 . Video . . December 29, 2023 . https://web.archive.org/web/20231229152226/https://www.youtube.com/watch?v=wWYZ90lAUOk . December 29, 2023 . live.
  14. 1762236880207184017 . wapodavenport . The FAA has closed the mishap investigation into the second Starship test flight. . Christian . Davenport . February 26, 2024 . March 7, 2024.
  15. SpaceX Performs Third Attempt of B10/S28 Wet Dress Rehearsal . March 4, 2024 . Video . en . . March 4, 2024 . March 6, 2024 . https://web.archive.org/web/20240306151314/https://www.youtube.com/watch?v=D1Eg_FltUZk&ab_channel=NASASpaceflight . live .
  16. Web site: Berger . Eric . Eric Berger (journalist) . March 6, 2024 . The next Starship mission has a tentative launch date: March 14 . March 7, 2024 . . en-us . March 6, 2024 . https://web.archive.org/web/20240306144340/https://arstechnica.com/space/2024/03/the-next-starship-mission-has-a-tentative-launch-date-march-14/ . live .
  17. Web site: Reisinger . Don . March 7, 2024 . SpaceX Starship Mission 3: How to Watch the March 14 Launch . March 8, 2024 . . en . March 8, 2024 . https://web.archive.org/web/20240308222341/https://www.cnet.com/science/space/spacex-starship-mission-3-how-to-watch-the-march-14-launch/ . live .
  18. Web site: Commercial Space Transportation License No. VOL 23-129 Rev. 2 . March 13, 2024 . . March 13, 2024 . March 13, 2024 . https://web.archive.org/web/20240313204852/https://www.faa.gov/media/69476 . live .
  19. SpaceX Launches Starship Test Flight #3 . March 17, 2024 . . March 17, 2024 . https://web.archive.org/web/20240317124624/https://www.youtube.com/watch?v=G2LM6zt9Mmw . live .
  20. Web site: ON THE PATH TO RAPID REUSABILITY . SpaceX.com . May 24, 2024 . https://web.archive.org/web/20240524141356/https://www.spacex.com/updates/#flight-3-report . May 24, 2024.
  21. SpaceX Launches Third Starship Flight Test . March 14, 2024 . . https://web.archive.org/web/20240314154312/https://www.youtube.com/watch?v=RrxCYzixV3s . March 14, 2024 . live.
  22. Web site: Clark . Stephen . SpaceX celebrates major progress on the third flight of Starship . March 16, 2024 . March 14, 2024 . March 16, 2024 . https://web.archive.org/web/20240316013647/https://arstechnica.com/space/2024/03/after-its-third-test-flight-spacexs-starship-could-soon-carry-satellites/ . live .
  23. Web site: ON THE PATH TO RAPID REUSABILITY . SpaceX.com . May 24, 2024 . https://web.archive.org/web/20240524141356/https://www.spacex.com/updates/#flight-3-report . May 24, 2024.
  24. Web site: Starship's Third Flight Test . . March 7, 2024 . March 6, 2024 . https://web.archive.org/web/20240306183144/https://www.spacex.com/launches/mission/?missionId=starship-flight-3 . live .
  25. Web site: SpaceX planning rapid turnaround for next Starship flight. March 19, 2024 . March 20, 2024.
  26. Web site: Despite problems, SpaceX hails progress after third test of Starship rocket . live . https://web.archive.org/web/20240315123017/https://www.aljazeera.com/news/2024/3/14/despite-problems-spacex-hails-progress-after-third-test-of-starship-rocket . March 15, 2024 . March 16, 2024 . Al Jazeera.
  27. Web site: March 14, 2024 . FAA Statements on Aviation Accidents and Incidents . https://web.archive.org/web/20240314192027/https://www.faa.gov/newsroom/statements . March 14, 2024 . March 15, 2024 . FAA.
  28. Web site: SpaceX planning rapid turnaround for next Starship flight. March 19, 2024 . March 20, 2024.
  29. News: FAA: no current plans to tax commercial space launches . SpaceNews . April 10, 2024 . April 14, 2024 .
  30. Web site: Marcia Smith on X: "At media bfg at Space Symp now, FAA/AST's..." . April 10, 2024 . X . April 22, 2024 .
  31. Web site: Beil . Adrian . May 22, 2024 . The FAA has corrected the date of submission by SpaceX for the safety determination. Quote below. . May 22, 2024 . X (formerly Twitter).
  32. Web site: Musk sees fourth flight of SpaceX's Starship in 3-5 weeks . May 12, 2024 . May 12, 2024 .
  33. News: Adrian Bell on X: "Statement of FAA provided to ..." . May 18, 2024 . Adrian Bell . X . May 18, 2024 .