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Starship flight test 4

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Starship flight test 4
Mission typeSuborbital flight test
OperatorSpaceX
Mission duration1 hour, 6 minutes, 10 seconds
Spacecraft properties
SpacecraftStarship Ship 29
Spacecraft typeStarship
ManufacturerSpaceX
Start of mission
Launch dateJune 6, 2024, 12:50:00 (June 6, 2024, 12:50:00) UTC (7:50 am CDT)[1]
RocketSuper Heavy (B11)
Launch siteStarbase, OLP-A
End of mission
Landing date
  • Booster: June 6, 2024, 12:57:30 UTC[1]
  • Spacecraft: June 6, 2024, 13:55:57 (June 6, 2024, 13:55:57) UTC[1]
Landing site
Orbital parameters
RegimeSuborbital
Periapsis altitude−15 km (−9.3 mi)[2]
Apoapsis altitude213 km (132 mi)[3]
Inclination26.8°[4]

Mission patch

Starship flight test 4 was the fourth flight test of the SpaceX Starship launch vehicle. The prototype vehicles flown were the Starship Ship 29 upper-stage and Super Heavy Booster 11.[5][6] SpaceX performed the flight test on June 6, 2024.

The main test objectives of this flight, both of which were accomplished, were for the Super Heavy booster to simulate a landing at a "virtual tower" just above the surface of the Gulf of Mexico, and for Starship to survive at least peak heating during atmospheric re-entry.[7]

This marked the first integrated test flight where both Starship and Super Heavy successfully reentered and performed a powered vertical landing over the ocean surface.

Background

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Investigation prior to launch

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Starship flight test 3 in March 2024 attained full duration burns of both stages and reached orbital velocity[citation needed]. However, both stages were destroyed during atmospheric return, prompting a SpaceX-led mishap investigation overseen by the FAA. The FAA stated that a completed license modification, incorporating corrective actions and meeting other requirements, was required for a launch license to be granted for this flight, the fourth flight test.[8][9]

SpaceX stated in early April that it would intend to attempt a booster landing with the tower arms on the fifth flight test if the booster virtual landing is successful during the fourth flight test.[10] In late April, a NASA official confirmed SpaceX remained on track for the fourth test flight to occur in May 2024.[11]

The communications license necessary for Flight 4 was granted by the FCC on April 18.[12] On May 17, SpaceX asked that the FAA make a public safety determination regarding the third flight test, which would allow SpaceX to launch the test flight while the mishap investigation is in progress if determined there was no public safety danger.[13] The FAA concluded the investigation on May 28 and determined that the third flight test had not threatened public safety.[14][15] SpaceX received regulatory approval to launch from the FAA on June 4.[16]

Starship flight test 4 was initially scheduled to launch on June 5, but was pushed back a day to June 6.[17] For this fourth flight test, the FAA listed three specific outcomes that would not trigger a mishap-investigation: the ship burning up during reentry, the flaps not having sufficient control of the ship, or the Raptor 2 engines failing to relight for landing.[18]

Vehicle ground testing

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Booster 11 and Ship 29 were first spotted around August 2022. Both stages underwent multiple cryogenic proof tests in late 2023, with Ship 29 performing a spin prime test in March 2024.[19] Following Starship's third test flight, Ship 29 was lifted onto Suborbital Pad B for two static fire tests in late March, and was later returned to the High Bay for pre-flight modifications. A 33-engine static-fire was conducted on Booster 11 on Orbital Launch Mount A on April 5. Booster 11's hot-staging ring was installed in early May.[20] Ship 29 was lifted onto Booster 11 on May 15,[21] followed by a partial propellant load test on May 16.[22] A wet dress rehearsal (WDR) was conducted on May 20.[23]

On May 28, SpaceX performed a second wet dress rehearsal of S29 and B11,[24] and on May 30, SpaceX installed the flight termination system (FTS or AFSS) on B11 and S29.[25] On June 5, S29 was stacked on top of B11 for the fourth and final time.[19] SpaceX intentionally omitted two TPS (Thermal Protection System) tiles and replaced one with a thinner tile to test how the loss of tiles would affect the ship.[26]

Changes from the previous flight

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During Starship's third test flight, the booster was destroyed just before splashdown due to engine failures caused by filter blockage of liquid oxygen to the engines. The ship was destroyed during reentry, due to excessive roll rates caused by clogged roll control valves. As a result, modifications were made to Booster 11's oxygen tanks to improve propellant filtration capability, while hardware and software changes were implemented to improve Raptor startup reliability. Additional roll control thrusters were added to the ship to improve attitude control redundancy.[27][28]

Several changes were spotted on Ship 29, including updates to the TPS tile adhesive and layout. B11 received upgrades such as reinforcements of tanks and additions to improve rigidity and durability.[29] The largest horizontal tanks in the orbital tank farm were made operational, supplementing the older vertical tanks that were being retired. Suborbital Pad B was decommissioned in May 2024, and vehicle testing operations were moved to Massey's Test Site to make room for the construction of Orbital Launch Mount B.[30]

Flight

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The mission profile for Starship flight test 4 was very similar to that of the third flight test, with the propellant transfer demonstration, the payload bay door demonstration, and the Raptor engine relight demonstration being omitted. There was also the addition of the jettisoning of the Super Heavy's hot staging ring two seconds after the shutdown of the boostback burn, and Starship was to attempt a landing flip and landing burn.[31][32]

One of the 33 Raptor engines on Booster 11 failed to stay lit during the initial burn, and one of the thirteen used for the landing burn failed to light. Neither engine failure affected the outcome of the flight because of redundancy in the multiple-engine design. To reduce mass during descent, a temporary design change on this test flight was used to jettison the booster hot-staging ring.[33][non-primary source needed] Longer term, the hot-staging ring is intended to be redesigned for lighter weight and tight integration with the booster and will not be jettisoned.

B11 successfully conducted a powered vertical landing over the Gulf of Mexico, splashing down into the ocean.[34] The booster was destroyed after tipping over, and part of the engine section was recovered in September 2024.[35] Bill Gerstenmaier stated that the booster landed "with half a centimeter accuracy."[36]

After completing a full duration burn of all six engines, Ship 29 successfully re-entered the atmosphere, maintaining attitude control despite significant visible damage to the structure and loss of some number of heat shield tiles.[31] Following the hypersonic descent through the atmosphere, S29 performed a powered vertical landing above the ocean before splashing into the Indian Ocean.[37] Elon Musk said that the ship maintained subsonic control but landed approximately 6 kilometers (3.7 mi) away from the target splashdown location.[38]

Flight timeline

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Time Event[39] 6 June 2024
−01:15:00 Flight director conducts a poll and verifies go for propellant loading Go for propellant loading
−00:49:00 Starship fuel (liquid methane) load start Success
−00:47:00 Starship oxidizer (liquid oxygen) load start Success
−00:40:00 Super Heavy fuel (liquid methane) load start Success
−00:37:00 Super Heavy oxidizer (liquid oxygen) load start Success
−00:19:40 Booster engine chill Success
−00:03:30 Booster propellant load complete Success
−00:02:50 Ship propellant load complete Success
−00:00:30 Flight director verifies go for launch Go for launch
−00:00:10 Flame deflector activation Success
−00:00:03 Booster engine ignition All 33 engines ignited with 1 shutting down at T+00:00:03
00:00:02 Liftoff Success
00:01:02 Throttle down for max q during ascent (moment of peak mechanical stress on the rocket) Success
00:02:46 Booster most engines cutoff (MECO) Success
00:02:51 Starship engine ignition and stage separation (hot-staging) Success
00:02:57 Booster boostback burn startup Success
00:03:47 Booster boostback burn shutdown Success
00:04:04 Hot-stage jettison Success
00:07:04 Booster is transonic
00:07:09 Booster landing burn startup 12 of 13 engines ignited[40]
00:07:30 Booster landing burn shutdown and splashdown Success
00:08:37 Starship engine cutoff (SECO) Success
00:44:54 Starship entry Vehicle damaged on re-entry
01:00:50 Estimated time of max q during Starship's descent Success
01:03:17 Starship is transonic
01:03:38 Starship is subsonic
01:05:36 Starship landing flip Success
01:05:39 Starship landing burn Success
01:05:56 Starship splashdown Within the target area, but 6 km (3.7 mi) off center

Reactions

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The flight was hailed as a success and marked the first time the Super Heavy booster and Ship achieved controlled splashdowns. A FAA clause for Flight 4, which would allow SpaceX to continue with additional flights of the same profile without a mishap investigation as long as no public safety issues occurred, was upheld as the flight did not encounter a mishap outside of the three exceptions.[41][42] On June 12, the FAA announced that they would not be requiring a mishap investigation for Flight 4 because all flight events occurred within the scope of planned and authorized activities.[43] This was the first Starship flight test to not require an investigation.

References

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  1. ^ a b c "STARSHIP'S FOURTH FLIGHT TEST". SpaceX. June 6, 2024. Archived from the original on June 1, 2024. Retrieved June 6, 2024.
  2. ^ McDowell, Jonathan (June 23, 2024). "Jonathan's Space Report No. 834". planet4589. Retrieved November 8, 2024.
  3. ^ Scott Manley (June 6, 2024). SpaceX's Starship Literally Melted! But It Kept Flying To A Miraculous Landing!. Archived from the original on June 7, 2024. Retrieved June 6, 2024 – via YouTube.
  4. ^ McDowell, Jonathan (June 23, 2024). "Jonathan's Space Report No. 834". planet4589. Retrieved November 8, 2024.
  5. ^ "SpaceX Revving Up for Starship Flight 3: | Starbase Update". NASASpaceFlight. January 29, 2024. Archived from the original on January 29, 2024. Retrieved February 13, 2024.
  6. ^ Bergin, Chris [@NASASpaceflight] (March 7, 2024). "We are live with testing of Ship 29, which is the upper stage of the fourth Starship Flight Test" (Tweet). Retrieved May 11, 2024 – via Twitter.
  7. ^ Davenport, Justin (April 19, 2024). "As IFT-4 prepares for launch, Starship's future is coming into focus". NASASpaceFlight.com. Archived from the original on May 6, 2024. Retrieved May 3, 2024.
  8. ^ "FAA Statements on Aviation Accidents and Incidents". FAA. March 14, 2024. March 14, 2024, Commercial Space / Boca Chica, Texas. Archived from the original on May 3, 2024. Retrieved May 5, 2024.
  9. ^ "Marcia Smith on X: "At media bfg at Space Symp now, FAA/AST's..."". X. April 10, 2024. Archived from the original on May 7, 2024. Retrieved May 5, 2024.
  10. ^ Bergin, Chris (April 6, 2024). "Some interesting notes". X (formerly Twitter). Archived from the original on April 6, 2024. Retrieved April 6, 2024.
  11. ^ Beil, Adrian (April 28, 2024). "NASA Updates on Starship Refueling, as SpaceX Prepares Flight 4 of Starship". NASASpaceFlight.com. Archived from the original on April 30, 2024. Retrieved May 3, 2024.
  12. ^ "License granted: Space Exploration Technologies Corp. (SpaceX) Dates: 04/25/2024-10/25/2024 Purpose: Launch vehicle communications for test flight mission launching from Starbase, TX". Archived from the original on June 7, 2024. Retrieved May 5, 2024.
  13. ^ Beil, Adrian (May 17, 2024). "Statement of FAA provided to @NASASpaceflight about SpaceX led investigation". X (formerly Twitter). Archived from the original on June 7, 2024. Retrieved May 17, 2024.
  14. ^ Bell, Adrian (May 30, 2024). "As SpaceX Completes Second Starship WDR, FAA Closes Safety Investigation Into Flight 3". NASASpaceflight. Archived from the original on May 30, 2024. Retrieved May 30, 2024.
  15. ^ Beil, Adrian (May 28, 2024). "Statement by the FAA provided to @NASASpaceflight". X (formerly Twitter). Archived from the original on May 29, 2024. Retrieved May 28, 2024.
  16. ^ "VOL 23_129 SpaceX Starship Super Heavy rev 3.pdf". drs.faa.gov. Archived from the original on June 4, 2024. Retrieved June 4, 2024.
  17. ^ Wall, Mike (June 3, 2024). "SpaceX targeting June 6 for next launch of Starship megarocket". Space.com. Archived from the original on June 3, 2024. Retrieved June 4, 2024.
  18. ^ Clark, Stephen (June 5, 2024). "We know Starship can fly—now it's time to see if it can come back to Earth". Ars Technica. Archived from the original on June 5, 2024. Retrieved June 5, 2024.
  19. ^ a b "Speeding on to Flight 4: The Chronology of S29 & B11". Ringwatchers. June 9, 2024. Retrieved June 16, 2024.
  20. ^ Weber, Ryan (May 5, 2024). "Ship 30 set to Static Fire next week as Flight 4 Preparations Continue". NASASpaceFlight.com. Archived from the original on May 7, 2024. Retrieved May 7, 2024.
  21. ^ NASASpaceflight (May 15, 2024). Fullstack: SpaceX Stacks Ship 29 on Booster 11. Archived from the original on May 15, 2024. Retrieved May 15, 2024 – via YouTube.
  22. ^ SpaceX Tests the Full Stack of the Fourth Starship Flight Test. Archived from the original on May 20, 2024. Retrieved May 16, 2024 – via www.youtube.com.
  23. ^ NASASpaceflight (May 20, 2024). SpaceX Performs Wet Dress Rehearsal of Fourth Starship Flight Stack. Archived from the original on May 20, 2024. Retrieved May 20, 2024 – via YouTube.
  24. ^ "x.com". X (formerly Twitter). Archived from the original on May 29, 2024. Retrieved May 30, 2024.
  25. ^ Starship Gazer (May 30, 2024). "FTS (Flight Termination System) explosives are being installed on both Ship 29 and Booster 11 this morning for the upcoming Starship test flight 4. Very exciting pre-launch milestone!". X (formerly Twitter). Archived from the original on May 30, 2024. Retrieved May 31, 2024.
  26. ^ "x.com". X (formerly Twitter). Archived from the original on June 6, 2024. Retrieved June 6, 2024.
  27. ^ "SpaceX - Updates". SpaceX. May 24, 2024. Archived from the original on June 13, 2024. Retrieved June 16, 2024.
  28. ^ Robinson-Smith, Will (June 6, 2024). "SpaceX accomplishes first soft splashdown of Starship, Super Heavy Booster on Flight 4 mission". Spaceflight Now. Retrieved June 16, 2024.
  29. ^ "Building Upon Accomplishments: What's New on Starship 29 & Booster 11?". Ringwatchers. June 7, 2024. Retrieved June 16, 2024.
  30. ^ Morales, Mia (June 16, 2024). "SpaceX begins building second Starbase launch tower, week after fourth launch". ValleyCentral.com. Retrieved June 17, 2024.
  31. ^ a b "Starship finds success on fourth flight test". June 5, 2024.
  32. ^ "Following IFT-3 milestones, SpaceX prepares for fourth Starship flight". March 22, 2024.
  33. ^ "STARSHIP'S FOURTH FLIGHT TEST". SpaceX.com. May 24, 2024. Archived from the original on June 1, 2024. Retrieved May 24, 2024.
  34. ^ SPACE.com, Mike Wall. "SpaceX Starship Blasts through Plasma on Return from Ambitious Test Flight". Scientific American. Archived from the original on June 6, 2024. Retrieved June 6, 2024.
  35. ^ Mike Wall (September 24, 2024). "SpaceX fishes Starship Super Heavy booster out of the sea (photo)". Space.com.
  36. ^ Foust, Jeff (October 9, 2024). "NASA "really looking forward" to next Starship test flight". SpaceNews. Retrieved October 13, 2024.
  37. ^ Harwood, William (June 6, 2024). "SpaceX's Super Heavy-Starship rocket launches on "epic" test flight". CBS News. Archived from the original on June 6, 2024. Retrieved June 6, 2024.
  38. ^ Youtube.com, Ellie in Space (June 7, 2024). "Elon Musk discusses Starship's 4th Flight". YouTube. Archived from the original on June 7, 2024. Retrieved June 7, 2024.
  39. ^ "Starship's Fourth Flight Test". SpaceX. May 24, 2024. Archived from the original on June 1, 2024. Retrieved May 24, 2024.
  40. ^ "Starship Flight Four". SpaceX. Archived from the original on June 1, 2024. Retrieved June 7, 2024.
  41. ^ Daleo, Jack (June 6, 2024). "SpaceX Starship's Fourth Test Flight Is Rocket's Most Successful Yet". FLYING Magazine. Archived from the original on June 6, 2024. Retrieved June 6, 2024.
  42. ^ Foust, Jeff (June 6, 2024). "Starship survives reentry during fourth test flight". SpaceNews. Archived from the original on June 6, 2024. Retrieved June 6, 2024.
  43. ^ Masso, Steven (June 12, 2024). "FAA not requiring investigation into fourth Starship launch". ValleyCentral. Retrieved June 17, 2024.