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New Glenn Update

blueorigin.com

51–60 of 154 posts

Re: New Glenn Update

#51

I REALLY wish they would stop displaying ft, mi, lbs. It actually angers me.

Good lord, find something else to be angry about. Decades of metric vs imperial threads should have you convinced by now that no matter how hated they are, these units aren't going away any time soon.

Re: New Glenn Update

#54
post #5
post #2

Interesting that "...additional vehicle upgrades include a reusable fairing..." I wonder how they'll be implementing that since SpaceX gave up on recapturing fairings (seemingly too soon, but only from the POV of someone with no internal info).

https://en.wikipedia.org/wiki/SpaceX_fairing_recovery_progra... > SpaceX performs some amount of cleaning and refurbishing before using the previously flown fairings on a subsequent flight. SpaceX has reflown fairing halves more than 300 times, with one being reflown for 34 times. They gave up on catching them in nets, because it turns out they're fine splashing directly into the water.

Thanks for the updated info!

Re: New Glenn Update

#55

Earlier quoted context omitted.

NASA still had much smaller jumps in capability between flights. Check out the Smarter Every Day NASA talk.

> Check out the Smarter Every Day NASA talk FYI, that talk was poorly received in the aerospace community. Destin missed that the entire point of Artemis is not to one and done the Moon again but build towards getting to Mars. And the repeated "we're going, right?" shtick was condescending in the same way Hegseth wanting generals to cheer and holler for him was. He acted like a petulant influencer. Not a science comm…

That was my interpretation of that talk. It seemed like a regurgitation of opinions of an old aerospace engineer. But that's probably unfair to Dustin, I believe that he actually came to that conclusion himself. But it was a really incorrect take that SLS was somehow the "safe bet" in comparison to betting on Starship. The whole talk just seemed insane based on what I knew about both programs.

Re: New Glenn Update

#56
post #33

Earlier quoted context omitted.

Falcon Heavy is a huge outlier, and has never actually demonstrated the capability to lift close to its nameplate capacity to LEO. Falcon 9 is already volume constrained to LEO outside of Starlink or Dragon launches, and Starlink is packed incredibly densely to get to that point. When I ran the numbers some time back, New Glenn was similar to Falcon 9. Increasing thrust by 15% doesn't just increase payload by 15%. I…

The really big change will be launch thrust to weight ratio. Going from ~1.2 to ~1.35 gives you 75% more thrust at launch which means you spend less time fighting gravity, less time in the thick parts of the atmosphere, and less time to get past the trans-sonic region.

There are other constraints on how quick the vehicle should be, even when engine performance allows: you probably won't want to hit maximum dynamic pressure in too-thick air.

Re: New Glenn Update

#57

Earlier quoted context omitted.

Starship can fly to orbit, it's just not cheaper than a reusable falcon 9 that way

Starship has only flown 11 times. I suspect it's more cost effective than the Falcon 9 was when it had 11 launches, long before any reuse.

Counting all those explosions as "flown" is pretty charitable.

Re: New Glenn Update

#58

Earlier quoted context omitted.

> Check out the Smarter Every Day NASA talk FYI, that talk was poorly received in the aerospace community. Destin missed that the entire point of Artemis is not to one and done the Moon again but build towards getting to Mars. And the repeated "we're going, right?" shtick was condescending in the same way Hegseth wanting generals to cheer and holler for him was. He acted like a petulant influencer. Not a science comm…

AFAICT it's "getting to Mars" for SpaceX and their ecosystem, and "sustainable cislunar economy" for Nasa, ULA and Blue Origin and their respective ecosystem. For example, see ULA's "cislunar 1000" concept from ~10 years ago. Either way, your criticism of Destin's presentation hits. One and done'ing the Moon is not particularly helpful in setting up a sustainable cislunar economy.

> it's "getting to Mars" for SpaceX and their ecosystem, and "sustainable cislunar economy" for Nasa, ULA and Blue Origin and their respective ecosystem

In 2017 Space Policy Directive 1 amended the national space policy to pursue "the return of humans to the Moon for long-term exploration and utilization, followed by human missions to Mars and other destinations" [1]. This formally established the Artemis program [2].

Destin's criticisms were apt for Constellation [3], which was closer to an Apollo reboot. They were uninformed for Artemis.

[1] https://trumpwhitehouse.archives.gov/presidential-actions/pr...

[2] https://en.wikipedia.org/wiki/Artemis_program

[3] https://en.wikipedia.org/wiki/Constellation_program

Re: New Glenn Update

#59

Earlier quoted context omitted.

Yup, the thrust improvements were expected. The BE-4 engines have quite a low chamber pressure for their engine class, so they can gain significant performance just by increasing chamber pressure. Additionally, the New Glenn fairings are very large for their weight capacity. New Glenn has 3x the fairing volume compared to the Falcon Heavy, but can throw less mass. So many expected that BO designed it this way because…

The numbers: BE-4 is 140 bar chamber pressure vs SpaceX Raptor 2 at 350 bar. Thrust to weight of BE-4 is 80:1 vs Raptor2 at 140:1. I don't think the capabilities are as different as those numbers imply. I believe that it's due to the conservativeness of Blue Origin and SpaceX's willingness to blow up hundreds of engines on the test stand to iteratively push the margins.

I believe Raptor 2 operates at a lower chamber pressure. According to Wikipedia, Raptor 3 is 350 bar, and its thrust to weight ratio is 183.6:1.

BE-4's chamber pressure is low for its design, but it would be very difficult to increase it to Raptor's levels. Full-flow staged combustion causes the propellants to be gasses when they enter the combustion chamber, and chemical reactions in gasses happen more quickly, allowing for efficient combustion in a smaller combustion chamber. The smaller volume makes it easier to contain higher pressures.

Re: New Glenn Update

#60

This is also good news for SpaceX. Satellite and payload designers generally design to common fairing sizes so they have a choice in launch providers. The 8.7m 9x4 fairing is similar to the 9m Starship fairing so more designers will now be designing payloads that use the full Starship capacity.

Such standardization will set a design envelope for the Golden Dome weapons..
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