Amazon is turning a corner with its launch providers, but ULA's Vulcan remains grounded.
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Amazon turns to Jeff Bezos’ other company to do some heavy lifting
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I gotta admit that's an impressive turn-around on their cadence compared to the past.
Time will tell how much it improves, though.
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I am curious how a frozen hydraulic line leads to reduced thrust. Would this be more of some sensor noting the condition and the on-board computer proceeding into a protocol which restricted thrust on that engine?
(If that is the case, I question the wisdom of a protocol which will avoid a possible engine 'anomaly' but - if enacted - will inevitably result in the payload being lost...)
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Total guess, but how are the valves on the propellant lines actuated? If they're hydraulic, a frozen line could lead to a valve not opening properly.
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VC6 is the heaviest variant of Vulcan offered, and uses 6 SRBs
* EDIT * corrected on maximum number of Atlas V SRBs by EllPeaTea below
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Atlas V could use up to 5 SRBs. The heaviest flown version was the 551 (5 metre fairing, 5 SRBs, 1 RL-10). (There’s a theoretical 552 variant that was never flown).
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Statistical
Ars Legatus Legionis
If you want to get crazy the delta II had up to 9 SRBs. 6 ignited on the ground and another 3 of them ignited in the air. Then you could add an optional 3rd stage Star solid rocket motor. That was the height of SRB mania.
It is time to let SRBs go for orbital launch vehicles. The whole "it keep defense contractors going" has proven to be a completed dud of a concept. If you want your defense companies to have the ability to make ballistic missiles then pay them to make ballistic missiles.
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Not a typo, Vulcan supports six SRBs. Required so it can handle some large DOD launches.
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One thing to note is that while Blue's integration and launch prep and so forth teams have gotten that faster cadence, we still don't know about their refurbishment times for the booster. The first one to be recovered took about 5 months until it flew again, but what's flying next week is a new booster. They're still refurbing booster #2 after the April launch. Presumably that will be a faster process than the first time, but how much faster remains to be seen. Until Blue bulks out their booster fleet (I think they said #4 is coming in the fall sometime) that's probably going to be their rate-limiting step.
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It feels like their software isn’t as robust as SpaceX - why didn’t it just burn longer on reduce thrust or if necessary on a single engine?
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So is 48 the maximum number of Leo satellites that NG can launch or the maximum number that they can stomach losing if something fails?
Things that must go right on next launch:
a) Corrective action from last launch
b) untested multi-satellite ejector
Things that must go right on next launch:
a) Corrective action from last launch
b) untested multi-satellite ejector
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New Glenn flight 3 had a very strange flight profile to go to a simple LEO destination. The target orbit was at 460 km with a 49.4° inclination. This is easy to get to from the east coast of the US by launching directly into that orbital plane, with a small circularization burn after a coast phase.
But that's not what Blue Origin did. They launched New Glenn into a far lower inclination (somewhere in the mid-30°s), requiring a needless multi-km/s second stage plane change burn. Normally launches avoid doing plane changes unless they're unavoidable — you need a plane change to go into a lower inclination than the launch site's latitude, but can usually go into higher inclinations directly.
The second stage valiantly did a more than 1 km/s plane change and orbit raising burn, but even that wasn't enough due to the chosen launch trajectory. It ended up in a 265 × 485 km orbit with 43.0° inclination, far short of the 49.4° inclination needed for a useful orbit. Had Blue Origin simply gone into the proper inclination in the first place, the underperformance wouldn't have mattered for the main mission.
But that's not what Blue Origin did. They launched New Glenn into a far lower inclination (somewhere in the mid-30°s), requiring a needless multi-km/s second stage plane change burn. Normally launches avoid doing plane changes unless they're unavoidable — you need a plane change to go into a lower inclination than the launch site's latitude, but can usually go into higher inclinations directly.
The second stage valiantly did a more than 1 km/s plane change and orbit raising burn, but even that wasn't enough due to the chosen launch trajectory. It ended up in a 265 × 485 km orbit with 43.0° inclination, far short of the 49.4° inclination needed for a useful orbit. Had Blue Origin simply gone into the proper inclination in the first place, the underperformance wouldn't have mattered for the main mission.
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It theoretically can do 60+ once it has been rated nearer to full performance, but 48 (near 30 tonnes of sats) is all it can apparently do at the moment.
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Yeah I assume they wanted to use the extra performance they had on the table from such a light LEO payload to test a long coast and big burn like what they would do on GTO missions. They did a relatively short coast (like 10 min) and relight on flight 2, but flight 3 was more like an hour. I guess one can say the test was successful, in that it revealed a potential problem with a long coast. Can't imagine AST was too happy with the result though.
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I'm pretty sure the 48 satellite payload was set before the April launch had its issue, so (a) presumably wasn't a factor when Amazon was speccing things out. It's probably a combination of (b) plus Blue still being conservative with NG and not running it with anything close to the nominal max payload.
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See HiggsForce's comment above, they took a relatively inefficient path by inserting into a lower inclination eccentric orbit, coasting, and then doing a combined perigee raise and plane change in LEO. The second burn of the upperstage was over a minute long, it would have burnt through 25-30 tonnes of prop. It's quite probable that with the one engine underperforming due to the hydraulic issue it did not have sufficient performance to make orbit and simply ran out of prop.
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In addition to the above responses, how much of Falcon 9's software has changed since flight #3? Why wasn't Falcon able to land within three attempts? Software robustness, perhaps?
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That's pretty much the only option unless booster #4 is a lot further along than they've said. Booster 2, even if there's no streamlining of the refurb process, should be ready to go in September. Making the reasonable guess that they'll go faster having had some practice, August seems plausible.
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Cool, I've just seen the two SRB variant so I presumed that's it. Artemis 6 taps out at 4 SRBs so I felt six is getting into KSP territory.
You have to admit that dial-a-rocket approach has some attraction if you're doing expendable builds as you're throwing only the amount of SRBs into the sea you actually need.
Then again, we pretty much should be letting expendable rockets go at this point.
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Well, so much for that. NG-4 just blew up on its pad during a static fire test.
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I guess we can write off New Glenn for the rest of the year.
Apologies for the X link, but it's all we've got at the moment:
View: https://x.com/NASASpaceflight/status/2060164928472854821
Edit: Local news is saying the boom was heard 45 miles away.
Apologies for the X link, but it's all we've got at the moment:
View: https://x.com/NASASpaceflight/status/2060164928472854821
Edit: Local news is saying the boom was heard 45 miles away.
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Yeah, if you wanted to know what one of those looks like and goes up like with that much fuel...you just saw it. It didn't destroy Titusville, and it looked like the erector survived the blast (although damaged possibly beyond repair).
The RUD was spectacular, though. Gonna be used in a Top 10 RUDs for a while.
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That won't buff out, and yeah that was quite the explosion don't have too much trouble believing that it was pretty loud. And depending on how much was done to the pad it could be quite a bit longer than that.
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There's a frame in that video right after the detector saturates where there's a very visible condensation cloud behind what looks to be a spherical shock. That sucker transitioned to detonation quickly!
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I'd bet those Lightning Towers will need to be replaced, as well as all the Non-Concrete parts of the Pad.
Huge setback, and we are back to one Heavy lift vehicle for a year or so.
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The one advantage SpaceX had when Amos-6 took out SLC-40 was that they were well into getting LC-39A ready for crew launches. Their return to flight would have taken much longer if not for that. Blue does have some other pads in the works, not sure anyone of them is far enough along to be quicker to stand up than rebuilding LC-36. But yeah this is definitely pushing Artemis towards SpaceX. About the only other one that might benefit from this is ULA. That sniper is getting pretty prolific at this point.
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Given it happened on engine start and Vulcan uses the same engines, until they can rule out the engines as a cause I'd bet this would ground Vulcan too.
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In the Spaceflightnow vid you can see the two towers at the beginning and then after the fireball one of the towers is just gone. The lighting arrestor at the top of the other had some pretty violent swaying as well.
View: https://www.youtube.com/watch?v=1O90WZJALYc
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Yes, since they were talking about launching Vulcan with no SRB's. So oddly yep.
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So what you're saying is they've got a functional second stage? Yeah, those don't get very far on their own.
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Vulcan has a functional first and second stage, it's currently grounded due to the SRB issues, but there were plans to launch it without any SRB's for certain light loads. However since it's first stage also uses 2 BE-4's as does New Glenn and one of those may or may not be the culprit on New Glenn, that pretty much wipes out any possibility of launching Vulcan until that's ruled out. Two rockets, same engines.
Hope that helps explain it.
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Yeah idk, looking at the video it is hard to tell where the explosion starts. There is obviously fire at the bottom of the rocket, and it looks to me to be way more than one would expect from a static fire. That could just be a function of the darkness though, it tends to make things look more dramatic. But there does seem to be a second fireball in the second stage a few seconds later, and right after that goes off the entire stack goes up. BE-4 also has a pretty good track record at this point, so I would tend to think that it wasn't likely to be the root cause.
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