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Blue Origin thread.


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51 minutes ago, CatastrophicFailure said:

AJRD just got a contract to build eighteen more... :P

Yeah, I saw. 100 M each. How is that even possible?

If Sandia Labs was buying new computer monitors and I formed a small business to sell them to them, would they buy monitors from me for 10 to 100 times what they should be paying? Dunno how you get that sort of deal.

ULA is using 2 Be-4s on Vulcan, right? Be-4 is basically an RS-25 level engine. Lower Isp, but it doesn't need high Isp on a booster, anyway. Vulcan is supposed to be ~80M/launch. What % are the 2 engines?

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That crew compartment is tiny. The docking node is what, 1255 mm across?

T35dn.jpg

The crew section is maybe 2.5m diameter? That would make it ~19-20m3.

So 4X the Apollo LM. That's certainly better than LM sized, but still pretty small for extended stays. maybe I'm ruined by the composite images of it next to the superyacht that is Starship.

 

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43 minutes ago, tater said:

That would make it ~19-20m3

About the same volume as Orion. And they’ll have a bit of gravity, so it’s somewhat more comfortable than the capsule.

51 minutes ago, tater said:

maybe I'm ruined by the composite images of it next to the superyacht that is Starship.

Yeah, hard to beat that luxury flying skyscraper. 

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53 minutes ago, mikegarrison said:

I would be surprised if the market for people willing to spend tens/hundreds of thousands of dollars on a 15 minute rocket flight has not significantly contracted in last three months.

It has flown multiple commercial non manned flights who is also demo flights but paid for. 
its an marked for testing stuff in zero over longer time than the vomit comet can manage, in space is an bonus. 
 

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I did not mean to imply they no longer have any customers at all, but just that the overall economic environment is very different than it was in January, and this certainly must affect how desperate (or not) they are to get into revenue service soon.

Edited by mikegarrison
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1 hour ago, mikegarrison said:

I did not mean to imply they no longer have any customers at all, but just that the overall economic environment is very different than it was in January, and this certainly must affect how desperate (or not) they are to get into revenue service soon.

I'm pretty sure they're not desperate for revenue at all, considering they still have 120 years or so of being able to shovel 1 billion dollars per year into the company.

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Is there any info on NG S2 wet/dry mass and BE-3U Isp? I’m asking because the officially released payload mass to GTO seems too low for NG. To LEO: 45t; To GTO: 13t. Compare it to FH: 63t to LEO, 26.7t to GTO (expendable). The reason why GTO throw seems too low to me is because NG has BE-3U-powered hydrolox upper stage with higher Isp compared to MVac. Payload mass should fall off slower for NG, and its GTO throw should be a higher fraction of LEO throw compared to FH. In reality, however, for NG this ratio is 0.29, and for FH it’s 0.42, which is very odd. Is wet/dry mass ratio of NG S2 really that bad?

Edited by sh1pman
Mixed up GTO and TLI payload
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1 hour ago, sh1pman said:

Is there any info on NG S2 wet/dry mass and BE-3U Isp? I’m asking because the officially released payload mass to TLI seems too low for NG. To LEO: 45t; To TLI: 13t. Compare it to FH: 63t to LEO, 23t to TLI (expendable). The reason why TLI throw seems too low to me is because NG has BE-3U-powered hydrolox upper stage with higher Isp compared to MVac. Payload mass should fall off slower for NG, and its TLI throw should be a higher fraction of LEO throw compared to FH. In reality, however, for NG this ratio is 0.29, and for FH it’s 0.37, which is very odd. Is wet/dry mass ratio of NG S2 really that bad?

I would assume the Be-3 Isp must be over 400. 440s is a number I have seen thrown around. 450 should easily be possible.

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Just now, tater said:

I would assume the Be-3 Isp must be over 400. 440s is a number I have seen thrown around. 450 should easily be possible.

Yeah, that's why it seems strange to me. Other rockets with hydrogen upper stages seem to be performing better on high energy orbits. For SLS Block 2, TLI/LEO mass ratio is 0.35. For Atlas V 551 it's 0.47. For Delta IV Heavy it's 0.55!

NG is a black sheep in this family, performing even worse than a FH with kerolox US. The only logical explanation for it is that its upper stage has a terrible wet/dry ratio. 

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5 hours ago, sh1pman said:

Is there any info on NG S2 wet/dry mass and BE-3U Isp? I’m asking because the officially released payload mass to TLI seems too low for NG. To LEO: 45t; To TLI: 13t. Compare it to FH: 63t to LEO, 23t to TLI (expendable). The reason why TLI throw seems too low to me is because NG has BE-3U-powered hydrolox upper stage with higher Isp compared to MVac. Payload mass should fall off slower for NG, and its TLI throw should be a higher fraction of LEO throw compared to FH. In reality, however, for NG this ratio is 0.29, and for FH it’s 0.37, which is very odd. Is wet/dry mass ratio of NG S2 really that bad?

FHe releases payload closer to orbital velocity than NG, which may have some impact.

Also, where are you getting NG with 13 tonnes to TLI? BO's website says NG can send 13 tonnes to GTO. For comparison FHe can send 26.7 tonnes to GTO.

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4 hours ago, sh1pman said:

Other rockets with hydrogen upper stages seem to be performing better on high energy orbits. For SLS Block 2, TLI/LEO mass ratio is 0.35. For Atlas V 551 it's 0.47. For Delta IV Heavy it's 0.55!

NG is a black sheep in this family, performing even worse than a FH with kerolox US. The only logical explanation for it is that its upper stage has a terrible wet/dry ratio. 

Other rockets with hydrogen upper stages likely stage at significantly higher velocities than NG, since NG has to re-enter and land. 

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37 minutes ago, sevenperforce said:

Also, where are you getting NG with 13 tonnes to TLI? BO's website says NG can send 13 tonnes to GTO. For comparison FHe can send 26.7 tonnes to GTO.

Yeah, mixed up the two numbers. Should be mass to GTO for both rockets.

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1 hour ago, sevenperforce said:

Other rockets with hydrogen upper stages likely stage at significantly higher velocities than NG, since NG has to re-enter and land. 

Yes Atlas, SLS, delta heavy and Ariane 5 is all 2.5 stages rockets. With SRB this is probably the best design for an disposable rocket. For reuse you prefer two stages.

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4 hours ago, magnemoe said:

Yes Atlas, SLS, delta heavy and Ariane 5 is all 2.5 stages rockets. With SRB this is probably the best design for an disposable rocket. For reuse you prefer two stages.

I have to wonder if sometime in the future we will see designs more like Falcon Heavy (possibly with smaller side boosters, maybe even asparagus staging).

Two stages seems to imply that each should have roughly equal delta-v.  But then you have all the issues of needing much more thrust on the first stage.  Side boosters would help, and would be the easiest to recover.  Just don't expect such things to be common until fuel costs start to equal the costs to refurbish and relaunch reusable rockets (fairly far in the future, thus the idea that asparagus staging might no longer be such a problem.  It doesn't add all that much in real life).

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