15/05/2025
Inside the Upgrades Powering Starship’s Ninth Flight Test
By The Space Spies Team | May 15, 2025
SpaceX’s Starship program is charging toward its ninth flight test, slated for no earlier than May 21, 2025, and the stakes couldn’t be higher. After back-to-back upper-stage failures in Flights 7 and 8, SpaceX has been hard at work refining the world’s most powerful rocket. Starship Flight Test 9, featuring Ship 35 (S35) and Booster 14 (B14), promises to showcase a suite of upgrades aimed at overcoming past challenges and pushing the boundaries of reusable spaceflight. The Space Spies team has dug into the details—sourced from SpaceX updates, industry reports, and chatter on X—to bring you the lowdown on what’s new for this critical mission.
A Block 2 Ship with Lessons Learned
Starship’s upper stage, known simply as “Ship,” is flying its Block 2 configuration for the third time with Ship 35. Introduced in Flight 7, Block 2 is slightly taller than its predecessor, boasting redesigned forward flaps, improved batteries, enhanced avionics, and a new fuel feed line system for its Raptor vacuum engines. However, Flights 7 and 8 exposed a critical flaw in this design, with both ships disintegrating less than 10 minutes after liftoff due to vibrations in the propellant lines causing fires in the engine bay. SpaceX has since zeroed in on this issue, and Flight 9 is set to test fixes aimed at stabilizing the propellant system.
According to posts on X, SpaceX has tweaked the fuel feed lines to mitigate the “POGO” issue—a harmonic oscillation that can disrupt engine performance. A detailed analysis shared by suggests that this problem remains a tough nut to crack, with a high chance of failure if not fully resolved. SpaceX’s iterative approach—fix, fly, and learn—means Ship 35 is a guinea pig for these refinements, with the goal of achieving a stable ascent and controlled reentry.
Heat Shield Overhaul: Surviving the Fiery Plunge
One of the most anticipated upgrades for Flight 9 is to the heat shield, which failed to get a proper test in the last two flights due to the upper stage’s premature demise. Ship 35 sports a revamped thermal protection system, including fewer heat shield tiles, new active-cooled tiles, ablative materials, and a secondary ablative layer to bolster reentry survival. These changes aim to withstand temperatures up to 2,600°F (1,430°C) during atmospheric reentry. The forward flaps have also been redesigned—made thinner and angled to reduce heating—addressing a weak point exposed in earlier tests. The heat shield upgrades are critical for SpaceX’s ambition to make Starship fully reusable. A successful reentry and splashdown in the Indian Ocean would validate these changes and pave the way for future orbital flights, potentially including a tower catch attempt in Flight 10 or beyond. The inclusion of reinforced catch pins on Ship 35 hints at SpaceX’s long-term goal of catching the upper stage with the launch tower’s “chopstick” arms, though this is likely delayed until at least Flight 10.
Super Heavy Booster: Reusability Milestone
Flight 9 marks a historic first for Starship: the reuse of a Super Heavy booster. Booster 14, which flew successfully on Flight 7 and was caught by the launch tower’s mechanical arms, will fly again with 29 of its 33 Raptor engines being flight-proven. This is a major step toward SpaceX’s vision of rapid reusability, akin to an airplane’s turnaround time. A static fire test on April 3, 2025, confirmed B14’s readiness, with SpaceX touting its reliability after a successful eight-second burn.
Booster 14 also benefits from prior upgrades introduced in earlier boosters, such as electric thrust vector control (TVC) actuators for smoother engine gimbaling, upgraded engine shielding, and larger purge tanks to prevent methane buildup and engine bay fires. These changes, first implemented on Booster 9, have proven effective, with B14’s successful catch in Flight 7 demonstrating the robustness of the design.
Experimental Payloads and In-Space Maneuvers
Flight 9 isn’t just about fixing past failures—it’s also pushing Starship’s capabilities forward. Ship 35 is expected to carry Starlink simulator satellites, mimicking the size and weight of next-generation Starlink V2 satellites, to test payload deployment. This follows Flight 7’s attempt, which didn’t reach the deployment phase due to the ship’s explosion. A single Raptor engine relight in space is also planned to demonstrate precise trajectory control, a key requirement for orbital certification and future missions like NASA’s Artemis lunar landings.
The mission profile includes a suborbital trajectory with a targeted splashdown off Western Australia, stressing the redesigned flaps and heat shield under real-world conditions. SpaceX is also testing experimental active-cooled tiles and an ablative heat shield material to gather data for future iterations. These experiments are crucial for validating Starship’s ability to handle the rigors of deep-space missions to the Moon and Mars.
Testing the Fixes: Static Fire Successes and Setbacks
SpaceX has been rigorous in pre-flight testing for Ship 35. The upper stage underwent three rounds of cryogenic testing at Massey’s Test Site on March 11 and 12, followed by multiple static fire tests. A single-engine static fire on April 30 simulated an in-space burn, while a six-engine, 64-second static fire on May 12—the longest ever for a Starship upper stage—demonstrated the vehicle’s endurance. However, a six-engine test on May 1 showed an abnormal shutdown at 36 seconds, hinting at lingering issues with the propellant system. SpaceX rolled Ship 35 back to Mega Bay 2 for inspections before completing the May 12 test, suggesting confidence in their fixes.
Booster 14’s static fire on April 3 was a smoother affair, building on its proven track record from Flight 7. These tests are critical for ensuring that both stages can handle the stresses of launch and reentry, especially given the FAA’s ongoing investigation into Flight 8’s failure.
The Road Ahead: Challenges and Ambitions
Flight 9 is a make-or-break moment for Starship’s Block 2 design. The repeated failures of the upper stage in Flights 7 and 8 have raised questions about the new propellant system’s reliability, with experts like Zack from warning that the POGO issue could persist. The FAA’s approval, pending the closure of the Flight 8 investigation, adds regulatory pressure to SpaceX’s timeline. A notice to mariners suggests a launch window between May 13 and May 23, with May 21 as the working target.
Success in Flight 9 would restore confidence in Starship’s path to full reusability and orbital capability, critical for deploying next-generation Starlink satellites and supporting NASA’s Artemis program. Failure, however, could delay these goals, though SpaceX’s iterative philosophy ensures that each test—successful or not—brings valuable data. Elon Musk himself has downplayed setbacks, noting that with thousands of planned flights for the 9-meter Starship, Flight 9 is “barely a bump in the road.”
Why It Matters
Starship’s ninth flight test is more than just another launch—it’s a proving ground for technologies that could redefine space exploration. From reusable boosters to advanced heat shields, SpaceX is laying the foundation for affordable, high-frequency missions to Earth orbit, the Moon, and Mars. The Space Spies team will be watching closely as SpaceX aims to turn the lessons of failure into the triumphs of tomorrow. Stay tuned for our coverage and analysis of Flight 9.
Space Spies is your go-to source for cutting-edge space news and insider insights. Follow us for updates on Starship and beyond!
