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Blue Origin thread.


Vanamonde

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What would a New Armstrong configuration have looked like? The Blue Origin descent element for the National Team lander was planned to have used two BE-7 engines. But if they were proposing a single-element, integrated reusable lander, they might have gone in a different direction.

The BE-3 can deep throttle to around 18%, and Bezos has talked about the closed dual expander BE-7 having similar capabilities. If we assume ad arguendo that the open-expander version of the BE-3U has similar deep-throttling ability, then it could conceivably throttle as low as 128 kN in a landing engine configuration. Padding it to around 135 kN to allow margin for hover, etc., then a single-element integrated lander using a single BE-3U as its landing engine would weigh in at around 83 tonnes at landing.

For safety reasons, of course, you wouldn't want to be limited to only a single engine. But that's where Blue could borrow from the old Soviet LK lander design. The BE-7 produces 44.5 kN, so placing four of those around the BE-3U would give the lander a nice clean abort mode as well as alternative landing engines. The BE-3U engine bell is around 2.5 meters across and the BE-7 is less than a meter wide, so they could all fit easily in a quincunx within a 7-meter circle, with space for landing legs as well.

A lander needs 2.6 km/s to get from NRHO to the lunar surface, and the same for the return trip. Assuming ~445 s of specific impulse for the open expander BE-3U, you'd need to leave NRHO weighing in at around 151 tonnes and you'd get back to NRHO after the mission with a burnout mass of around 45 tonnes.

What do we know about the New Glenn upper stage? Well, estimates of its dry mass put it around 16-18 tonnes, and it is believed to carry around 175 tonnes of propellant.

If "New Armstrong" was to be Lunar Starship knockoff based on the New Glenn upper stage, then it would be able to launch on the reusable New Glenn first stage, reaching LEO with around 17 tonnes of propellant residuals. After three New Glenn refueling launches with hydrolox propellant transfer, it would have 150 tonnes of propellant on board, enough to perform its own TLI and insertion at NRHO with 40 tonnes of residuals. 

With that approach, New Armstrong would need to take on about 66 tonnes of additional propellant at NRHO in order to get down to the lunar surface and back. As luck would have it, a New Glenn second stage which is fully refueled in LEO can perform its own TLI and insert at NRHO with 67 tonnes of residuals. That same New Glenn second stage would have reached LEO with 45 tonnes of residuals, requiring just three New Glenn refueling launches to be ready.

Obviously there would need to be some dry mass added for maneuvering, docking, prop transfer, and the like. But I'm probably sandbagging how much propellant New Glenn can put in LEO with each launch, so I think it still closes just fine.

So Blue Origin could have proposed a single-element "New Armstrong" integrated lander which would require only 8 New Glenn launches (rather than the 12-15 Superheavy launches required for Lunar Starship), based on the New Glenn upper stage. It would have about 28 tonnes for a crew cabin, additional structure, power generation, propellant management, landing legs, and lunar surface payload. And the hatch would have been 11 meters closer to the lunar surface than Starship's.

Blue would argue that the 100-tonne+ capability of Lunar Starship is overkill and that cutting the number of required launches almost in half reduces complexity and schedule risk. If they did make an argument, it would definitely explain how the Court described their protest:

Quote

"Oh. That's what the agency wanted and liked best? If we had known, we would have instead submitted a proposal that resembled the successful offer, but we could have offered a better price and snazzier features and options."

 

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With 100t of residuals and the nominal 1200t of props for SS, then you get 13 launches for SS. 1 for the depot, 11 more to fill it, then the 13th is the LSS itself. You could use the LSS as the depot, and remove 1 launch. Stretching the LSS tank slightly makes sense from math we've done here, which might add a launch to fill.

If SS can do more like 150t, then 9 launches to fill the stretched tank., leading to 10-11 in total.

Am I missing something?

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36 minutes ago, Beccab said:

The rest of the post is speculation, but this is incorrect. It is what BO claims, but that's not even the biggest lie on the infographic

 

30 minutes ago, tater said:

With 100t of residuals and the nominal 1200t of props for SS, then you get 13 launches for SS. 1 for the depot, 11 more to fill it, then the 13th is the LSS itself. You could use the LSS as the depot, and remove 1 launch. Stretching the LSS tank slightly makes sense from math we've done here, which might add a launch to fill.

If SS can do more like 150t, then 9 launches to fill the stretched tank., leading to 10-11 in total.

Am I missing something?

Elon has claimed that it will only take 8 refueling launches max, citing 150 tonnes of residuals per launch and speculating that it may even take fewer launches if Lunar Starship is lightweight enough (lacking flaps and a heat shield) to make the trip without full tanks. Indeed, if they can get the dry mass of Lunar Starship down to 60 tonnes and if we assume 40 tonnes of crew cabin and payload, it can do the trip from LEO to NRHO to the lunar surface and back to NRHO starting in LEO with only 970 tonnes of residuals in its tanks. With that approach and 150 tonnes of residuals delivered per launch, it would only need 5-6 refueling launches, since it would reach LEO with 135 tonnes of residuals for its own launch.

But nevertheless, I was citing the “12-15” number because that’s what Blue Origin was claiming and so that’s the argument they would have made to the court, whether true or no. 

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16 minutes ago, sevenperforce said:

But nevertheless, I was citing the “12-15” number because that’s what Blue Origin was claiming and so that’s the argument they would have made to the court, whether true or no. 

I think I did the math with a propulsive return all the way to LEO. Yeah, lower with only NRHO by a bunch.

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47 minutes ago, tater said:

I think I did the math with a propulsive return all the way to LEO. Yeah, lower with only NRHO by a bunch.

I still see propulsive return to LEO as a pretty long pole. If it weren’t for stupid Orion hanging out in NRHO, it would be easier, but the NHRO layovers make the whole trip a whopping 12.5 km/s. At 380 seconds for the RVacs (not accounting for any of the SL vac burns at lower efficiency), the required propellant fraction is 96.6%. Starship’s dry mass would need to drop to 42 tonnes to do that, with no payload at all. A tank stretch would only provide incremental improvements.

A propulsive return to GTO, where Starship tankers could easily meet it and give it the additional props to return to LEO, is a little easier. You’d need 10.2 km/s, which comes to a propellant fraction of 93.5%, giving you an allowable dry mass of 84 tonnes, which is closer to something useful.

45 minutes ago, tater said:

More on topic, it would be nice if BO would stop screwing around and build all the things. I want to see a 7m, reusable BO vehicle flying. I want all the things flying.

Agreed.

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13 hours ago, mikegarrison said:

Smear campaign?

Maybe I'm just jaded a little, but this is NOTHING like the knife-fighting in the commercial airline sales campaign world. If you guys really are fans of commercial space, you need to get ready for some competitive marketing. I kind of feel like I'm listening to people attending their first MMA match and overhearing them say, "Oh my god, they are beating each other up!"

Fair enough, I see where you are coming from.  However this isn't the airlines. I don't think its fair to compare an airline choosing between 737's and A320's (with relatively similar range, capacity, fuel burn, etc.) with NASA choosing between landers. One is a competition for actual capability and performance you are tailoring your mission to, the other is a contract for spares and after sales support since the aircraft are nearly identical in capability.

Edited by Meecrob
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23 minutes ago, sevenperforce said:

I still see propulsive return to LEO as a pretty long pole. If it weren’t for stupid Orion hanging out in NRHO, it would be easier, but the NHRO layovers make the whole trip a whopping 12.5 km/s. At 380 seconds for the RVacs (not accounting for any of the SL vac burns at lower efficiency), the required propellant fraction is 96.6%. Starship’s dry mass would need to drop to 42 tonnes to do that, with no payload at all. A tank stretch would only provide incremental improvements.

A propulsive return to GTO, where Starship tankers could easily meet it and give it the additional props to return to LEO, is a little easier. You’d need 10.2 km/s, which comes to a propellant fraction of 93.5%, giving you an allowable dry mass of 84 tonnes, which is closer to something useful.

Agreed.

I did the math in the HLS thread, and at 4mm steel, LSS would be ~42t metal. 12t of Raptors. Unsure what the crew area requires mass wise, 60t total seems plausible. At 3mm, total mass could be 44t dry, plus crew area, so 50t (same 6t). The tanks can easily be stretched to 1400t I think (can't find the post, my guess was using another 2 rings for props). At 2mm steel, the total dry mass drops to 38t.

Looks like for a 50t dry LSS we need 102t of props to propulsively get to LEO from NRHO. A 50t LSS can't close with 1400t props (stretched tank), but it's not outside the realm of possibility.

Of course I would assume that LSS with no crew can do a series of shallow aerobrakes and almost arbitrarily reduce the props needed to enter LEO. It can make as many passes as needed, after all, and those passes can be designed to not present a heating issue.

Any BO architecture could do the same...

 

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3 minutes ago, tater said:

The tanks can easily be stretched to 1400t I think (can't find the post, my guess was using another 2 rings for props).

An insider some time ago said that stretching the whole Starship of another ~8 meters is possible, so there's also that

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A 50t dry LSS (no cargo) can return to NRHO with 74t of residuals. Needs 14 for TEI. LSS is now headed for entry (shallow for multiple aerobrake passes) with 60t of props (2.9 km/s). Lunar entry velocity is ~11.1 km/s, and LEO is ~7.6 km/s. About 600m/s short of what LSS can do, so that's what needs to be scrubbed off. Passes would be thermally limited, and it might have to go tail first because of the solar up front. Wonder if the 2.9 km/s could be done as a series of entry burns at whatever the aerobrake depth is to create a propulsive bow shock? Some cosine losses if gimbaled out slightly, but that might end up a net positive if it changes the ballistic coefficient enough.

Way OT for BO, wonder what their plan is for a reusable lunar vehicle.

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8 hours ago, RCgothic said:

The hypocrisy is running attack ads "This is ridiculously complex and unsafe!" whilst proposing simultaneously behind closed legal proceedings to do exactly the same thing.

Have you never worked with  a marketing department? Or even seen one in action before now?

Look back at that Chevy truck ad. Now guess whether Chevy had ever studied whether to use an aluminum body on their trucks, before running that ad.

Anyway, as I said, my interpretation of this is that they looked at the tankering option, realized it was trading cost for risk, and thought that NASA wasn't going to like that trade. Then they were surprised and upset when NASA not only did like that trade but liked it enough to accept the risk with no backup.

None of this is surprising or shocking. In fact, in the world of high stakes competition for big contracts, it's (as I said before) rather tame.

3 hours ago, tater said:

More on topic, it would be nice if BO would stop screwing around and build all the things. I want to see a 7m, reusable BO vehicle flying. I want all the things flying.

I don't know that I see a market for this. There may never be such a vehicle if it doesn't have customers.

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29 minutes ago, mikegarrison said:

I don't know that I see a market for this. There may never be such a vehicle if it doesn't have customers.

That's certainly the problem for more traditional companies, particularly public companies beholden to shareholders.

BO, like SpaceX is different, they can build whatever they like as long as Bezos is writing the checks with his amazon stock. Bezos when talking about this specific aspect of the launch business likes to remind people that when he started amazon, he didn't have to invent credit cards or parcel delivery. He then says that what is needed is infrastructure, then space business can develop since those entrepreneurs don't have to invent the infrastructure, they can start with some in place.

 

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28 minutes ago, tater said:

That's certainly the problem for more traditional companies, particularly public companies beholden to shareholders.

BO, like SpaceX is different, they can build whatever they like as long as Bezos is writing the checks with his amazon stock. Bezos when talking about this specific aspect of the launch business likes to remind people that when he started amazon, he didn't have to invent credit cards or parcel delivery. He then says that what is needed is infrastructure, then space business can develop since those entrepreneurs don't have to invent the infrastructure, they can start with some in place.

The Spruce Goose is not remembered as a successful airplane. Sure, a trillionaire can fund a rocket program, but at the end of the day they need a mission. I'm not at all sure that "if you build it, they will come".

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8 minutes ago, mikegarrison said:

The Spruce Goose is not remembered as a successful airplane. Sure, a trillionaire can fund a rocket program, but at the end of the day they need a mission. I'm not at all sure that "if you build it, they will come".

I'm not, either. I'm just saying the 2 companies are more like that Howard Hughes program (not sure what his airplane company was called off hand) than Boeing, LockMart, etc.

The same goes for Mars. Clearly zero business case, just as I don't see a case for O'Neill colonies (BO desire). I'm all for both of them since I find it interesting, and costs me exactly nothing :D

 

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10 hours ago, sevenperforce said:

What would a New Armstrong configuration have looked like?

Never mind that, I wonder what they would even name the successor to New Armstrong. Hopefully, some (presumably required to be American) astronaut will do something heroic before the New Armstrong is retired, so there is an even more prominent name to attach to the even bigger and better rocket. At the moment, it's hard to top the first guy to walk on the Moon.

Edited by Codraroll
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On 11/20/2021 at 5:00 AM, StrandedonEarth said:

“New [first person to step on Mars”

Well now Musk has to go on the first manned mars mission :) 
The two seconds who step down have tongue twisting names, think Tamils. Just if you wanted to disqualify Musk for not being an pilot or scientist. 

 

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11 hours ago, magnemoe said:

Well now Musk has to go on the first manned mars mission :) 
The two seconds who step down have tongue twisting names, think Tamils. Just if you wanted to disqualify Musk for not being an pilot or scientist. 

 

Send Kimbal as the head botanist. (Elon's brother, who's been working on hydroponics-related stuff)

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On 11/19/2021 at 12:31 PM, mikegarrison said:

NASA not only did like that trade but liked it enough to accept the risk with no backup.

I'd argue that for NASA, having a robust and well-tested orbital refueling system is a more important development than going to the moon.  That's the key to the rest of the solar system. If I were them, I'd get that done, cancel the Starship lander, and re-open bidding for a more fit-for-purpose moon lander.

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1 hour ago, FleshJeb said:

I'd argue that for NASA, having a robust and well-tested orbital refueling system is a more important development than going to the moon.  That's the key to the rest of the solar system. If I were them, I'd get that done, cancel the Starship lander, and re-open bidding for a more fit-for-purpose moon lander.

Let's not change horses until we get a fuel depot up there.  After that major milestone is a reality - then you can put forth the better ideas 

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