SpaceX’s Starship program represents the future of interplanetary travel, but its journey has been anything but smooth. The eighth high-altitude test flight of Starship (SN8) ended in a dramatic explosion upon landing, raising questions about the spacecraft’s design and SpaceX’s approach to rapid prototyping.
In this article, we’ll break down why Starship SN8 exploded, the key lessons SpaceX learned, and the changes being implemented for future launches.
What Happened During Starship SN8’s Flight?
On December 9, 2020, Starship SN8 took off from SpaceX’s Boca Chica, Texas, facility, reaching an altitude of 12.5 km (41,000 feet). The flight test was largely successful in demonstrating key maneuvers, including:
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A controlled ascent with all three Raptor engines firing.
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A “belly-flop” descent, where Starship reoriented itself horizontally to increase atmospheric drag.
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A flip maneuver to reposition for landing.
However, during the final landing burn, one of the Raptor engines failed to reignite properly, causing insufficient thrust. As a result, Starship hit the landing pad at high speed and exploded in a massive fireball.
Why Did SN8 Explode?
SpaceX CEO Elon Musk later explained that the explosion was caused by two main factors:
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Low Fuel Tank Pressure During Landing
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Starship’s header tanks (smaller fuel tanks used for landing) did not maintain enough pressure to feed the Raptor engines properly.
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This led to a lean fuel mixture, causing one engine to fail during the critical landing burn.
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Hard Impact Due to Insufficient Thrust
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With only two engines firing instead of three, Starship couldn’t slow down enough before touchdown.
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The impact was too violent, rupturing the vehicle and causing the explosion.
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Despite the fiery ending, SpaceX considered the test a success because it achieved its primary objectives: testing aerodynamic control, engine performance, and the belly-flop maneuver.
What SpaceX Learned from SN8’s Failure
Failures are an expected part of SpaceX’s “test, fly, explode, iterate” development philosophy. The SN8 explosion provided crucial data that influenced subsequent Starship designs. Key takeaways included:
1. Improved Header Tank Design
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The header tanks were redesigned to ensure stable fuel pressure during critical maneuvers.
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Later prototypes (SN9-SN15) featured modified fuel systems to prevent similar issues.
2. Enhanced Engine Ignition Reliability
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SpaceX upgraded the Raptor engines to improve restart reliability.
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Changes included better spark ignition systems and refined fuel injection methods.
3. Stronger Landing Legs & Shock Absorption
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SN8’s landing legs were not strong enough to handle a hard impact.
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Future versions incorporated crushable structures to absorb landing forces.
4. More Robust Flight Software
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The flip maneuver was refined to ensure smoother transitions between flight phases.
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Autonomous flight algorithms were updated to better handle engine-out scenarios.
How SpaceX Applied These Lessons to Later Starship Tests
Following SN8, SpaceX rapidly iterated on the design with SN9, SN10, and SN11—each improving on the last.
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SN9 (February 2021) – Similar flight profile but also crashed due to an engine failure.
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SN10 (March 2021) – Successfully landed but exploded minutes later due to a methane leak.
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SN11 (March 2021) – Disintegrated mid-air due to an engine-related issue.
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SN15 (May 2021) – Finally achieved a fully successful high-altitude flight and landing.
The success of SN15 proved that SpaceX’s iterative approach worked, paving the way for orbital flight tests.
What’s Next for Starship? Upcoming Changes for Future Launches
SpaceX is now preparing for Starship’s next major test: an orbital flight. The company has made several key upgrades based on past failures:
1. Upgraded Raptor Engines (Raptor 2 & Raptor 3)
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More reliable ignition and higher thrust.
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Better thermal management to prevent overheating.
2. Hot-Staging for the Super Heavy Booster
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A new staging technique where Starship’s engines ignite before separation for smoother transitions.
3. Enhanced Heat Shield for Re-Entry
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Improved thermal protection tiles to survive orbital re-entry temperatures.
4. Faster FAA & Regulatory Approvals
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SpaceX is working closely with regulators to minimize delays for future launches.
Conclusion: Failure is Part of SpaceX’s Success
Starship SN8’s explosion was not a setback but a necessary step in SpaceX’s development process. By embracing failure and rapidly iterating, SpaceX has made tremendous progress toward making Starship the most powerful rocket ever built.
With each test, the spacecraft becomes more reliable, bringing humanity closer to missions to the Moon, Mars, and beyond. The next Starship launch will incorporate all these lessons—bringing us one step closer to the future of space travel.
