On Monday, May 12, SpaceX performed a long duration - 60 second - static fire test on Ship 35, apparently clearing the way for preparations for Flight Test 9, or FT-9, to resume at their normal pace - normal for SpaceX, not the industry in general. Video here.
Starship ignited its Raptor engines Monday morning on a test stand near SpaceX's Starbase launch facility in South Texas. The engine ran for approximately 60 seconds, and SpaceX confirmed the test-firing in a post on X: "Starship completed a long duration six-engine static fire and is undergoing final preparations for the ninth flight test."
SpaceX hasn't officially announced a target launch date, but maritime warnings along Starship's flight path over the Gulf of Mexico suggest the launch might happen as soon as next Wednesday, May 21. The launch window would open at 6:30 pm local time (7:30 pm EDT; 23:30 UTC). If everything goes according to plan, Starship is expected to soar into space and fly halfway around the world, targeting a reentry and controlled splashdown into the Indian Ocean.
If you haven't been watching the details, you might not know that in an attempted static fire on May 1st, there was an anomaly that either caused the software or the operators to abort the test. Video of the test here, from Lab Padre's weekly report, the video is queued to start just before the test. They report that 25 seconds into the 60 second test, one of engines sputtered and put out a bright flash that led to the test abort.
This is a high stakes test because of the previous two test flights ending in failures that seem to be related.
... SpaceX investigators, working under the oversight of the Federal Aviation Administration, determined the Starship test flight in January failed after propellant leaks led to fires in the rocket's aft compartment, or attic. This led to the early shutdown of the rocket's engines and eventual breakup.
Engineers concluded the leaks were most likely caused by vibrations during the ship's climb into space. The vibrations were in resonance with the vehicle's natural frequency, intensifying the shaking beyond the levels SpaceX predicted. For the next test flight on March 6, SpaceX made changes to the ship's feed lines routing fuel to its Raptor engines, made adjustments to propellant temperatures, and flew the engines at a new throttle setting.
The January test flight they're referring to was Flight Test 7. SpaceX hasn't released the results of the investigation into the Flight Test 8 failure, and the FAA hasn't yet issued a launch license for Flight 9. Likewise, SpaceX hasn't released any information on the changes it made to Starship for FT-9.
The booster for FT-9 is the first SuperHeavy booster that will be reused. The booster for FT-9 made its first flight in FT-7, when it soared to the edge of space, released the Starship upper stage, and returned to the launch pad, where it was caught in mid-air by the giant chopsticks. They will attempt to recover the booster after stage separation on this flight, too.
Screen grab from a video of FT-5 seconds before the successful grab, October
of '24. Image credit: SpaceX
Reusing the booster from FT-7 is a natural for the Starship program. After
all, they intend for the ship to be not just reusable, but rapidly
reusable. More like an airplane than any current rocket.
EDITED TO ADD 5/14/25 5:25 PM EDT: As of Wednesday afternoon, 5/14, NextSpaceflight shows the launch to be Wednesday evening, May 21st, at 7:30 EDT, 6:30 Central (local) time.
"The vibrations were in resonance with the vehicle's natural frequency,".
ReplyDeleteThe vehicle's natural frequency.... I wonder what frequency that is?
StarBase CSI did an excellent breakdown on a constantly occurring problem, quite fascinating history and ways its been dealt with.
DeletePOGO: The 63-Year-Old Problem Threatening Starship's Success
https://m.youtube.com/watch?v=GkqWhHvfAXY
Colored flames in green and blue may have signified one of the engines eating itself due to green coming from copper being burnt.
ReplyDeleteWill be interesting to see if the V2 Starship actually survives everything.
The frequency would be low, large heavy aircraft are in the 1Hz range, and below.
ReplyDeleteAs propellant burns off the frequency will rise. It may have passed through a resonant zone (actually, up to, but not - successfully- through), in which case the engine test was probably set up with a fuel load designed to test that specific condition.
Since the flyer was fixed to the ground it's natural frequencies will be higher than in free flight, so they might use a heavier propellant loading to bring frequencies down ( there are a number of tricks you can play with ground tests to simulate flight).
Thank you, I appreciate your time!
DeleteYes, thanks Anon 10:26. Appreciate the data fill-in.
DeleteDoes the Superheavy booster have any ability to land without being caught by the Chopsticks? From what I understand the mission profile options are "Return To Base and be caught" or "Expend at sea", with no option for landing on a droneship.
ReplyDeleteIf I understand what I've read, the next version of SuperHeavy will have landing legs. There are pictures of a SuperHeavy standing on ASOG or one of the offshore drone ships, like this one. Nothing official that I can definitely point to.
DeleteSomething very important is in process, like how they are going to attempt catching to Falcon boosters on one drone ship, think it was with a Falcon Heavy launch, its so they can catch the central booster also.
DeleteIf they are successful this launch, its gonna be epic. They sure have a fearless methodology with their iterative R&D, can not but greatly admire their accomplishments, its so far out front sometimes events obscure this greatness, its not that they are leading and altering aerospace technology, they are in a league of their own. I see Shotwell and Musk, and its subtle but obvious they are front men, because somebody who remains hidden is leading their endeavors, someone or somebodies who are the key to making things happen to where they are and unafraid of risk, and if anything it is risk that is the key component. Dare to risk, dare to tempt fate, it is like nothing else really, but whatever it is it is a driver of SpaceX.
ReplyDelete"I see Shotwell and Musk, and its subtle but obvious they are front men, because somebody who remains hidden is leading their endeavors, someone or somebodies who are the key to making things happen to where they are and unafraid of risk, and if anything it is risk that is the key component."
DeleteInstead of saying "front men" and "somebody who remains hidden," I think most of us say "executives" and "engineering managers" or simply "engineers." Musk is key in creating the corporate culture, and his drive to see people on Mars is driving the company, but the daily engineering decisions are what are keeping the company succeeding, or not. Very importantly, plus the way they choose new engineers. That is not, ever, a "Personnel" or "Human Resources" job. It's engineering management.
Might find this of interest Sig, a couple others have similarly made their own citizen journo dive, into the available information and intricacies, creating a view of how these people operate where most of us rarely see. For each of us make of it what they choose to see things.
Deletehttps://tlavagabond.substack.com/p/welcome-to-the-palantir-world-order
*Gulf of America
ReplyDeleteAs of me posting this, the booster will NOT be reused. No catch.
ReplyDeleteYMMV, this is SpaceX we are dealing with. They have a License to Change Their Mind, and do so frequently.