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Blue Origin Thread (merged)


Aethon

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I think I'll take everything with just a bit of salt on it. Within the time frame envision by Elon Musk, so much can happen and I have yet to see a veritable piece of the whole ITS infrastructure. They still haven't ironed out all the bugs in the F9, how will they develop an interplanetary ship for 100t of cargo/astronauts within a decade, test it, test it again, make a shakedown cruise and the lot before sending it to Mars in 2025-ish???

Even though funding is less likely to happen, I still find the step by step approach of NASA much more realistic (the methodology, not either funding nore timing!!!)... But we'll see...

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1 hour ago, kerbiloid said:

If not ISRU, why methane? Kerosene is not volatile, needs no cryogenics, its tanks are lighter, ISP isn't much less.

Engine performance. Can't do FFSC with kerolox.

1 hour ago, kerbiloid said:

IfISRU, how they would lift tens if not hundreds tons of liquid methane from Mars to the ship orbit. Hard to imagine a lander with multi-use 4 meter nozzles.

From the hints we have, we know the architecture has the transfer ship landing. There's only the booster rocket, a ship to fuel the transfer ship in earth orbit, and the transfer ship/lander.

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41 minutes ago, kerbiloid said:

Hard to imagine a lander with multi-use 4 meter nozzles

on a 12m diameter lander (direct mission) :

I imagine at least 3 big vac raptors in a triangle with one little atmos raptor in the middle. 

The atmos is used for the final 1000m (?) of earth landing, with the vacs being buttoned up.

Mars landing could be done this way too if u want to protect the vacs.

It is a big unit.

85t empty. 100t cargo out (25t back).

tank space for 1000t of fuel.

Launch barely fueled as 3rd stage on a 6500t bfr. Then 4 or 5 fueling missions. 

Finally LEO config ~1200t ~7000m/s in tanks.

Slightly faster TMI + adjustments cost 4400 m/s. 3 vac raptors produce 900t thrust at 380s. TWR 0.75

6 months transfer

Mars EDL start 360t, 2400m/s (125t effective w/ mars gravity) TWR vacs 7.2

  ----> this is the big unknown....some estimates of direct mars edl costs are as low as 1800m/s

          if u need more, lower the cargo tonnage

Mars surface 190t, 200 m/s (65t effective). Final Landing twr on atmos engine 3.5

550 days surface mission

isru generates 600t fuel

Mars surface return config 710t, 7000 m/s (230t effective) TWR is about 3.9 at liftoff.

MLO costs 4000 m/s

Earth transfer costs 2500 m/s

6 months transfer

Earth EDL start 125t, 400 m/s, TWR 2.0 , atmos raptor gives 250t thrust at 320s

Earth surface 110t, 100 m/s  

I have played fast and loose with the numbers here.

Ideas and corrections welcome.

57 minutes ago, StarStreak2109 said:

Mars in 2025

Agree. Every single item on the timeline would have to work first time.

It wont.

But I keep my fingers crossed.

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My jaw is still on the ground.

Its a direct mission. 2 stages.

127.8MN is 42(?) atmos raptors at 3MN sl each. 12m diameter.

Thats a 10000t rocket. Heh.

Booster stages at...2200m/s according to reddit crew.

Might actually land back in the launch clamps. Crikey!

So many engines.

ITS looks like " 9 engines on the MCT ITS - 6 vac/Mars and 3 SL (probably for landing) " from reddit

Edited by RedKraken
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The attaching of the fuel payload to the landed booster (2:00 in the video) was really fast. Are they actually planning to develop a system where a crane can just drop it in and launch like that? Or will the crew in LEO have to wait through the normal multi-week process of welding everything together, static fire tests, etc.?

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1 hour ago, HebaruSan said:

The attaching of the fuel payload to the landed booster (2:00 in the video) was really fast. Are they actually planning to develop a system where a crane can just drop it in and launch like that? Or will the crew in LEO have to wait through the normal multi-week process of welding everything together, static fire tests, etc.?

By the looks of it, they're aiming for turnaround in hours, not weeks. This has been a stated goal of SpaceX in the past. If they're running methane, that should make it more feasible too. 

 

 

Also, anyone know what time Scott Manley's livestream is tonight? It's on Twitch, now, right?

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6 minutes ago, CatastrophicFailure said:

By the looks of it, they're aiming for turnaround in hours, not weeks.


And the main reason we can't do it today is that nobody has prioritized it.  Meanwhile, back in the 1950's, back in the stone age of rocketry, they could fuel and prep an Atlas for launch in under an hour.

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2 minutes ago, DerekL1963 said:


And the main reason we can't do it today is that nobody has prioritized it.  Meanwhile, back in the 1950's, back in the stone age of rocketry, they could fuel and prep an Atlas for launch in under an hour.

SpaceX: Home of the Interplanetary Ballistic Missile

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3 minutes ago, DerekL1963 said:


And the main reason we can't do it today is that nobody has prioritized it.  Meanwhile, back in the 1950's, back in the stone age of rocketry, they could fuel and prep an Atlas for launch in under an hour.

Some people are. CASIC reckon they can do a Kuaizhou-1 or 1A launch a day after being given the order.

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18 minutes ago, DerekL1963 said:


And the main reason we can't do it today is that nobody has prioritized it.  Meanwhile, back in the 1950's, back in the stone age of rocketry, they could fuel and prep an Atlas for launch in under an hour.

 

13 minutes ago, Kryten said:

Some people are. CASIC reckon they can do a Kuaizhou-1 or 1A launch a day after being given the order.

The biggest obstacle to plug and play rocketry is non standardized payload, his proposal is to space what the Intermodal container was to terrestrial shipping.

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32 minutes ago, Kryten said:

Some people are. CASIC reckon they can do a Kuaizhou-1 or 1A launch a day after being given the order.

Apples and oranges to some degree...  A (mostly) solid fueled (and very low performance) launcher than can go through an extensive checkout procedure and then, after being put on standby, be ready in "under a day" is about as newsworthy as the sun coming up in the morning.  You'd have to seriously work at it to not meet that kind of readiness guideline.

What we're talking about above is turnaround, a very different process.  That's why I brought up fueling speed, because refueling is a vital part of that process.

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According to the specs on the booster given during Elon's IAC presentation, it appears the booster can be a single-stage-to-orbit launcher. See the specs in this collection of the slides from the presentation here:

http://imgur.com/a/20nku

You can calculate the delta-v possible for the stage to be well above the 9,100 m/s required for orbit when you use the 382 s vacuum Isp of the stage.

 

  Bob Clark

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3 hours ago, DerekL1963 said:

Apples and oranges to some degree...  A (mostly) solid fueled (and very low performance) launcher than can go through an extensive checkout procedure and then, after being put on standby, be ready in "under a day" is about as newsworthy as the sun coming up in the morning.  You'd have to seriously work at it to not meet that kind of readiness guideline.

What we're talking about above is turnaround, a very different process.  That's why I brought up fueling speed, because refueling is a vital part of that process.

Yes they have to refuel an rocket larger than saturn 5. 
Also a bit sceptical to landing on launchpad, is that even possible as in is it an flat surface to land on?
 

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Someone over on NSF (Speculation: SFR (mini-BFR) as fully reusable Falcon Heavy thread) ran some numbers and apparently the tanker vehicle might be. Needs the outer engine bells swapped out for sealevel ones, But saying 50-75 tons to leo. Even if it's much less it gets the thing some flight history. Win-win if it can do it.

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