Exoscientist

I’m willing to consider other possibilities. Someone give me another reason for doing a test that will literally never be used for a real flight, but never doing the test that needs to be used in every single flight. Bob Clark

Actually, this static test doesn’t give confidence in the Raptor reliability for reusability. It actually provides suspicion of the reverse. SpaceX’s plans for Mars and Moon missions using multiple refueling flights absolutely can not work unless the Raptor can do 3-burns in a single flight: the initial burn, the boostback or reentry burn, and the landing burn. SpaceX has literally done thousands of static burns of the Raptor of all kinds of different variations. Yet SpaceX has not done one single test of the Raptor doing 3-burns at the full mission burn lengths, full mission wait times between burns, and full mission power level. Instead of doing a test of this absolutely crucial capability for the SpaceX plan to work, it does a test instead of a capability it will literally never use. The only conclusion appears to be SpaceX has no confidence in the Raptor to do all 3-burns at the actual mission burn lengths, wait times, and power levels. Bob Clark

To get to the bottom of it the FAA should require SpaceX to release all videos of the engine bay while the engines are firing, most specifically during restarts. Bob Clark

That’s from flames bouncing up from the ground. You don’t see that at altitude. More relevant though are rockets that do landing burns. Not many but none of DC-X, New Shepard, or SpaceX’s own Falcon 9 have huge plumes of flame shooting up the side during their landing burns. Bob Clark

You have to guess that since SpaceX ain’t telling. Bob Clark

Someone needs to actually ask SpaceX about it, since SpaceX is not telling. A photographer took another angle of the flight 7 landing burn that showed also for this latest landing there was a large plume of flame shooting up the side: From the angle the SpaceX live feed showed, the size of the flame was not visible. Bob Clark

On this seminar series: Technosignature seminar series. https://seec.gsfc.nasa.gov/News_and_Events/technosignatureSeminars.html I found a talk: Simulation of the Earth’s radio-leakage from mobile towers as seen from selected nearby stellar systems Ramiro Saide, SETI institute January 17, 2024 An article describing their work is here: Can ET Detect Us? May 2, 2023 https://www.seti.org/press-release/can-et-detect-us It has a link to the research article. They first look at the case of total mobile(cell phone) tower emissions. They’ll extend it to total mobile(cell) phones, powerful civilian and military radars, and television and radio transmitters in follow-up work. They estimate total mobile towers are in the range of 4 GW total and at Barnard’s star distance of < 10 lightyears away would need 100 times more sensitivity than the Square Kilometer Array(SKA), equivalent to a 1 kilometer wide radio telescope. This would be 10 kilometers across. But when you add in together the other radio sources it might be smaller than this. There was a study on the upcoming Square Kilometer Array(SKA) that it could detect an airport radar 200 lightyears away: This Radio Telescope Could Detect Alien Airports. https://youtu.be/ayqyb8XCtE0 There are 260,000 stars within 200 lightyears of Earth. Robert Clark

Thanks for that link. If you read the section “Let’s talk about the black smoke and fire”, you’ll see there is some uncertainty as to whether all the flames were intentional venting or not. The author notes there was also black smoke from the rear of the rocket, which could have been thermal protection burning or some other parts in the engine bay including the engines on fire. As the author notes, all this could be resolved if SpaceX would say what happened, but SpaceX ain’t telling. Bob Clark

Flames can be seen coming out at the location of the aft flap hinge. The relative location of the hinge can be seen here: It appears to be below the rear tank dome and somewhat above the engines. This though doesn’t mean the leak and fire didn’t originate at the engines, but it could be that the flames become visible there outside because the hinge was the easiest point for the flames to escape. SpaceX should release any imaging inside the engine bay while the engines are firing. Bob Clark

I would say SpaceX doesn’t want to release images damaging to the idea the Raptors are reliable. For instance it still it did not release images of what happened at the end of the ocean touchdown of the booster IFT-4, when it was clear it exploded. And it has not said anything about the Raptor that exploded on the booster during the IFT-4 landing burn. It could dispel concerns the Raptor is still leaking and catching fire by releasing engine bay views of the booster and ship while the engines are firing, most specifically during the booster landing burns and the ship burns in this last flight. By the way, that Elon is apparently so sanguine about fires appearing in the engines bay in Starship raises questions if it is indeed the case fires arise in the engine bay during the booster landing, but SpaceX doesn’t care because they are “controlled”, so far. Bob Clark

There was no other reason for responding to this specific post of yours than you mentioned Discord. So I wanted to find out if that question was discussed on there. I don’t know which specific Discord forum this is. It wasn’t related to the cost issues. I’d like SpaceX to release those engines views it has available during the Starship engine firing, not just before, that clearly would be important for diagnosing the origin of the leak. Bob Clark

What’s the scuttlebutt on Discord and on Forum.NasaSpaceflight.com about the origin point of the leaks in the Starship in the last flight, the engines or the plumbing? If it were the engines then that is concerning because leaking Raptors was a focal point from the FAA after a prior failure in regards to items SpaceX needed to fix. The Raptors should not be still leaking fuel and catching fire this late in their development. There is no doubt that SpaceX knows the origin of the leaks. During the prior tests of the Starship landing procedures there were cameras in the engine bay that were able to image leaks when they occurred: What Happened to Starship SN11? | SpaceX Starship SN11 Test Flight & Explosion Cause Analysis. https://youtube.com/clip/Ugkx5eG9w2IgvyX_3yKJea8kUCbYcrNHpF1F?si=OYbJQXNgy-CbuguI There is no doubt such cameras are still in the engine bay during the Superheavy/Starship test flights. Bob Clark

This employment posting suggests they are considering 9 engines: Bob Clark

Bob Clark

It’s pretty clear they need to bump up the thrust. The easiest way to do that is add engines. SpaceX adds and subtracts number of engines to either stage of SuperHeavy/Starship like it’s a walk in the park. Increasing thrust to an engine in contrast involves significant engineering work. I wonder if Blue Origin didn’t go with 9 engines from the start just because they didn’t want to be seen as copying SpaceX. In any case, the low 25 ton payload they have now is probably because of that low TWR. If they want their planned 45 tons reusable, they’ll need that thrust upgrade. Bob Clark

FAA grounds SpaceX’s Starship after midflight explosion, reports property damage on Turks and Caicos. PUBLISHED FRI, JAN 17 20251:46 PM ESTUPDATED 6 HOURS AGO. SpaceX initially published a statement on its website Thursday that Starship debris fell “into the Atlantic Ocean within the predefined hazard areas,” seemingly contradicting the FAA’s explanation for why a “Debris Response Area” was activated. As of Friday morning, the latest SpaceX statement did not include that specific language. The company’s website said more broadly that “any surviving pieces of debris would have fallen into the designated hazard area” after the failure. The FAA, in response to CNBC’s request for clarification on whether Starship debris landed outside the predefined hazard area, reiterated that its “information is preliminary and subject to change.” SpaceX did not respond to a request for comment. https://www.cnbc.com/2025/01/17/faa-grounds-spacex-starship-reports-property-damage-in-caribbean.html Bob Clark

I like this review of the Raptors by Ultimate Steve: I agree with him that an engine not starting or not completing its burn counts as an engine failure. In addition to those he mentions, it is almost a certainty that a Raptor actually exploded during the landing burn on IFT-4, but SpaceX still has not come clean on this: Given that SpaceX has not been open about what happened during this prior landing burn, and given the Raptors prior history of leaking fuel and catching fire in flight, I consider it likely the flames seen shooting out the sides of the booster during both tower catches actually arose from Raptor fuel leaks. Consider, that giant 25 meter, 80 foot, tongue of flame shooting up the side of the booster during the prior catch was quite surprising and puzzling. Yet, SpaceX has said nothing about it. It's like they are acting like it never happened. That doesn't inspire confidence that it was something planned. Robert Clark

Flames were seen shooting out the side of this booster like during the last booster catch. Everyone ASSumes it’s just venting. But nobody asks SpaceX and SpaceX ain’t telling. ( And we all remember the warning about what can happen when you ASSume.) In view of a Raptor leaking fuel and exploding on the ship on this flight, and Raptors previously leaking fuel and catching fire in flight, the question should be asked: were the flames seen shooting out the sides of the booster during landing burns, including ones without a catch attempt, due to fuel leaks on the Raptors? A little vignette when it does come out there were fuel leaks during the landing burns, and these things always do come out: Space journalists: Why didn't you say fuel leaks were the cause of the flames shooting out the side of the booster during the landing burns? SpaceX: you never asked. Bob Clark

New Glenn must be underpowered as indicated by its too slow lift-off acceleration. NasaSpaceFlight commenters during their livestream said it so slow they thought it might not even complete the launch. Mystified why Blue Origin would even field it when they must know from the start they would have to upgrade engine thrust or number of engines. They should have done that from the beginning. The 4.51 million pound thrust in the first image is 2,050 tons, or 290 ton thrust per BE-4 engine, a 16% upgrade over the current BE-4’s 250 ton thrust. Upgrading to 9 engines using the current BE-4’s would be a 28.5% upgrade in total thrust. I’d go for the 9 engine upgrade. Gives even greater capability when you also upgrade BE-4 engine thrust, possibly reaching Saturn V 100-ton to LEO capacity. It could do single launch Moon missions.

Agree or disagree: it was a mistake for SpaceX to follow the failed N-1 approach to testing Starship. A Raptor failed both on the booster and on the ship, and on the ship one failed catastrophically. How many total test flights needed now just to make orbit with high payload? 10? A dozen? How many total to prove Raptor reuse reliability? 15? How many total to prove orbital refueling? 20? In contrast standard industry practice is to construct a separate, full test stand to do full up, full thrust, full duration testing. Done this way at least Starship could be doing expendable flights already by now, and with paying customers. Even Raptor reuse reliability could have been tested on the full test stand, providing a faster route to Starship reuse. The comparison of the Superheavy/Starship to the N-1 rocket has been claimed invalid as N-1 rocket engines could not be tested individually, whereas the Raptor engines are. But note a key fact: even when tested, Raptor engines still fail at high rate: SpaceX should withdraw its application for the Starship as an Artemis lunar lander. It is my contention the attempt of SpaceX trying to reach a 2025 deadline to have the SH/SS flying and with multiple successful test flights completed puts undue pressure on its normal safety procedures. For that reason my opinion is it should withdraw the Starship for consideration as a lander for the Artemis III lander mission. http://exoscientist.blogspot.com/2023/08/spacex-should-withdraw-its-application.html Robert Clark

Traditionally in the industry, individual stages are tested for full up, full mission length, full power burn on the test stand. Bob Clark

Thanks for that. That’s a pretty detailed appraisal of the test flights in regards to the Raptor. I have mentioned this before, but I really do not like this approach SpaceX is taking by testing Raptors all together for full mission burns only in flight tests. The typically way this is done in the industry is you construct a separate test stand for the full stage burn. And you test that over and over until you are confident all engines can burn reliably for the full lengths of the full mission burns. A separate full up test stand is an extra expense, but these now 7 test flights without an operational paying flight yet aren’t cheap either. An estimate is ca. $100 million construction cost for Superheavy/Starship, so ca. $700 million just in construction costs. When you add on operational costs this could total over $1 billion. A full up test stand would not have cost that much. Bob Clark

The proof is in the pudding, as they say. Two key things to look out for is how well the single reused engine performs on this flight, and how many engines from this flight will be reused on the following one. Robert Clark

IF it is scrapped would that include the engines? That would not speak well toward Raptor reusability. Bob Clark

But the one being now flown is essentially the same as flown last time. It would be a great proof of of reusability if the same engines were used. Bob Clark