REVEALED: Why Did SpaceX Starship 7 Explode?

Summary

In this video, the host discusses the causes behind the explosion of SpaceX's Starship 7 during its flight on January 16, 2025. An official investigation found that a propellant leak and harmonic response contributed to the failure. The leak occurred in the attic area, leading to a fire that caused the engines to shut down. The host proposes that the vehicle’s size change, potentially due to an increased liquid oxygen (LOX) tank, may have exacerbated the issue. SpaceX is already addressing these issues by implementing new venting and purge systems and working on upgrades for Starship 8, including Raptor 3 engines and structural improvements.

Takeaways

• 😀 SpaceX's Starship 7 exploded after an anomaly during its 7th flight test on January 16th, 2025.
• 😀 The investigation into the explosion was led by SpaceX, with oversight from the FAA, NASA, and the National Transportation Safety Board.
• 😀 The explosion was caused by a harmonic response, leading to excessive stress on the propulsion system and a subsequent propellant leak.
• 😀 The leak in the 'attic' (unpressurized area between the liquid oxygen tank and the heat shield) resulted in sustained fires and the eventual destruction of Starship 7.
• 😀 Starship 7's autonomous flight safety system (AFSS) triggered as expected and caused the spacecraft's breakup after communication was lost.
• 😀 SpaceX conducted an extended static fire test for Starship 8, incorporating flight data from Starship 7 to make improvements.
• 😀 The test revealed the need for hardware changes to the vacuum engines, fuel feed lines, and propellant temperatures to address fire risks in the attic region.
• 😀 Future Starship upgrades will include new Raptor 3 engines, which will reduce attic volume and minimize leak points.
• 😀 The Starship 8 flight test, scheduled for February 28, 2025, will include these updates and is expected to be on time, barring regulatory approval.
• 😀 The speaker speculates that the explosion could have been related to an increase in propellant by 25%, possibly requiring a larger liquid oxygen tank, causing structural changes and more stress during flight.
• 😀 The speaker emphasizes that while the theory is plausible, it's not official, and the community should consider it as one possible explanation for the incident.

Q & A

Why did SpaceX's Starship 7 explode during its flight test?

The explosion was caused by a harmonic response in the propulsion system, which led to increased stress and propellant leaks. These leaks resulted in sustained fires that ultimately led to the controlled shutdown of engines and vehicle breakup.

What is the harmonic response mentioned in the video?

A harmonic response refers to vibrations or oscillations caused by forces acting on the spacecraft, similar to a guitar string vibrating when plucked. In the case of Starship 7, this response grew stronger than expected, causing structural stress and contributing to the failure.

What role did the 'attic' play in the failure of Starship 7?

The attic is an unpressurized space between the liquid oxygen tank and the heat shield. During the flight, propellant leaks into this space, which exceeded the venting capability and resulted in sustained fires, contributing to the explosion.

What improvements are SpaceX making to address the issue with the attic?

SpaceX is adding additional vents and a purge system using gaseous nitrogen to make the attic area more robust to propellant leaks. This will help prevent the fires from spreading in future flights.

What changes are being made to Starship’s propulsion system?

The introduction of Raptor 3 engines will reduce the attic volume, eliminate most joints that could leak, and improve the overall robustness of the system to prevent failures like the one that occurred with Starship 7.

What was the role of the flight termination system (FTS) in the Starship 7 incident?

The FTS worked as intended and triggered the vehicle's breakup when communication was lost, preventing further damage. It was an autonomous response that followed the vehicle's predefined safety protocols.

Why did SpaceX add 25% more propellant to Starship 7?

The added propellant was likely intended to improve Starship's performance, but the increase in fuel volume could have contributed to structural changes and issues, such as the harmonic response, which led to the failure.

What do the changes to the Starship's design for Flight 8 include?

Flight 8 will incorporate new design elements, including strengthened vacuum engines, a new venting system, and improvements to the propellant feed lines and operating thrust targets. These changes are intended to address the issues from Flight 7 and improve performance.

What is the significance of the upcoming February 28th launch for Starship 8?

The launch of Starship 8 is significant because it will test the improvements made since Starship 7's failure, including structural changes, new engine designs, and advanced safety systems. Success could bring SpaceX closer to deploying Starlink version 3 satellites.

Why does the speaker suggest that the increased height of Starship 7 might be related to the LOX tank?

The speaker theorizes that the increase in height (1.8 meters) was likely due to a larger LOX tank designed to hold 25% more propellant. This change in the spacecraft's structure could have contributed to shifting fuel dynamics and harmonic response, leading to the failure.