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28 minutes ago, Ultimate Steve said:

Unless the rendezvous is lightning fast, the 80m/s margin will evaporate quickly.

Another thought...

The whole concept was predicated on the fact that DIVH already put Orion into an elliptical orbit in EFT-1. I'm merely assuming it can repeat the same feat a second time.

Orion's service module in EFT-1 was stated by NASA to be a dummy mass simulator, although I don't have confirmation that it was the same mass as the operational service module. It wouldn't make sense to call it a mass simulator if it didn't actually do the job of simulating the mass of the SM. That being said, if EFT-1's dummy SM was not actually on the order of 15 tonnes, then my math is screwed. However, the mission itself is not necessarily screwed. There are a lot of areas with margin. If D2 is lightened by the removal of internal systems (ECLSS etc) and burns off more of its props, and Orion can perform the final leg of the TLI, then it will still work.

I also suspect that Falcon Heavy will have even more residuals after taking Dragon 2 to LEO. I used the stated expendable payload to GTO in estimating residuals in LEO, which introduces a fair bit of conservatism. If I am more aggressive, then we recognize that taking a 26.7-tonne payload to GTO (2.27 km/s past LEO) requires 29 tonnes of residuals on LEO. This means it burned 78.5 tonnes of prop to get that 26.7-tonne payload into LEO, which means it needed 2.86 km/s from MECO-2 to MVac startup. But if it was carrying only 10.9 tonnes of Dragon 2 from MECO-2 to LEO instead of 26.7 tonnes, then that 2.86 km/s would only cost 69.5 tonnes of props, leaving the Falcon upper stage plus Dragon 2 in LEO with 38 tonnes of residuals.

Even if DIVH could not push Orion+SM past LEO at all (we know it can at least get it to LEO because Bridenstine said that math would work), those 38 tonnes of residuals would still be enough to push Dragon 2+Orion+SM 2.25 km/s past LEO, leaving about 480 m/s to Orion for completion of the TLI. Should leave Orion with enough dV to get in and out of DRO or at least NRHO.

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13 hours ago, Ultimate Steve said:

I tried Tundra, and at least the BFR portion didn't work. I'll see if I can get Dragon working. Any idea which Orion or Dragon mod would be best? Orion in particular, I've never looked at Orion mods before.

ReDirect by @benjee10 !

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51 minutes ago, sevenperforce said:

if EFT-1's dummy SM was not actually on the order of 15 tonnes, then my math is screwed.

Delta IV Heavy has a listed payload to LEO of 28.8 tons. If Orion is 25 tons total, that leaves only 3.8 tons of propellant to push the thing beyond LEO, and I haven't done the math but it seems fishy.

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Static fire possible any minute now.

 

Static fire!

 

 

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Just now, Ultimate Steve said:

Delta IV Heavy has a listed payload to LEO of 28.8 tons. If Orion is 25 tons total, that leaves only 3.8 tons of propellant to push the thing beyond LEO, and I haven't done the math but it seems fishy.

I wonder if the "mass sim" on EFT-1 was just structural and not actually the right weight.

28.8 tonnes to LEO means MECO-2 at 2.77 km/s short of LEO based on RL-10 isp and propellant load. With a 25.85-tonne payload, the DCSS can push 2.97 km/s, meaning only 200 m/s past LEO instead of ~1100 as I had anticipated.

Let's run with those numbers. The FHUS will need to burn about 3 tonnes of props past LEO to get itself and D2 up to a matching orbit with Orion. Let's imagine, to add some margin, that D2 burns off half its props in the rendezvous and docking, saving us about 0.7 tonnes. This means the mated stack can get about 2.14 km/s more out of the FHUS, pushing a total of 2.341 km/s past LEO...safely above GTO and around 390 m/s short of TLI. Definitely within Orion's capabilities. DRO might be a stretch but NRHO would be easy enough.

2 minutes ago, tater said:

Static fire possible any minute now.

 

Static fire!

 

 

It was ridiculously muffled on the livestream.

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17 hours ago, sevenperforce said:

Suggestion:

This sentence: "Immediately after Orion’s systems checked out and orbital inclinations aligned, Falcon Heavy would launch expendable, carrying an unmanned Dragon 2, into the same orbit."

Might read better as: "Immediately after Orion’s systems checked out and orbital inclinations aligned, Falcon Heavy would launch in an expendable configuration, carrying an unmanned Dragon 2 into the same orbit."

Other than that, the only potential issue I caught was the one @Ultimate Steve already mentioned, that the Dragon 2 docking port might not work. However, it would still be relatively cheap to develop a docking port with autonomous rendezvous as a FH payload.

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3 minutes ago, Mad Rocket Scientist said:

Suggestion:

This sentence: "Immediately after Orion’s systems checked out and orbital inclinations aligned, Falcon Heavy would launch expendable, carrying an unmanned Dragon 2, into the same orbit."

Might read better as: "Immediately after Orion’s systems checked out and orbital inclinations aligned, Falcon Heavy would launch in an expendable configuration, carrying an unmanned Dragon 2 into the same orbit."

Other than that, the only potential issue I caught was the one @Ultimate Steve already mentioned, that the Dragon 2 docking port might not work. However, it would still be relatively cheap to develop a docking port with autonomous rendezvous as a FH payload.

Thanks for the tip; I like that edit better.

The docking port can take the load, for sure; we just aren't sure whether the Dragon V2 pressure vessel can take that much axial, compressive structural loading. I am more worried about whether D2 can effectively rendezvous and dock while still connected to FH's upper stage. Developing a brand new docking port with its own rendezvous capability (effectively making Falcon 9's upper stage an expendable space tug) would be tremendous but it would actually be a LOT of development work. Practically starting D2 dev over from scratch. 

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This is all Block 5.

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Posted (edited)
19 minutes ago, Serpens Solidus said:

Does Block 5 mean it has 5 cores

Block 5 is the fifth main version of the Falcon 9. Nobody knows exactly what the naming system means, but a lot of people think that Falcon 9 1.0 was Block 1, 1.1 was Block 2, 1.2/Full Thrust was Block 3, Block 4 was a few upgrades to 1.2, and Block 5 is the current and most likely final version.

This Falcon Heavy is made up of three block 5 cores.

Edited by Ultimate Steve

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30 minutes ago, Ultimate Steve said:

Block 5 is the fifth main version of the Falcon 9. Nobody knows exactly what the naming system means, but a lot of people think that Falcon 9 1.0 was Block 1, 1.1 was Block 2, 1.2/Full Thrust was Block 3, Block 4 was a few upgrades to 1.2, and Block 5 is the current and most likely final version.

This Falcon Heavy is made up of three block 5 cores.

F636xiP.gif

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Posted (edited)

It was hard to tell that it was joke. Most jokes are at least a little bit funny.

Edited by mikegarrison

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Check out Musk's new profile pic of a new BFR render:

HKxtnLsO_400x400.jpg

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I realize that’s just a bad-S rendering and all, but would that even be possible? Have cryofuels ever been used in the rain like that? The ice buildup would be enormous...

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27 minutes ago, DAL59 said:

Check out Musk's new profile pic of a new BFR render:

HKxtnLsO_400x400.jpg

Why two crew walkways? 
Even if used P2P the elevator in the tower would be the bottleneck.
I assumed the superheavy would be feed from the bottom eliminating the need for an arm for it. 

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Posted (edited)
1 hour ago, DAL59 said:

Check out Musk's new profile pic of a new BFR render:

HKxtnLsO_400x400.jpg

Yeah, he's had that pic for a few days now. It's not official, it's by this guy:

 

 

Edited by ThatGuyWithALongUsername

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1 hour ago, DAL59 said:

Check out Musk's new profile pic of a new BFR render:

 

Ok, it's cool and all but does anyone else have the problem of when looking at it on twitter on his actual picture, you see this guy instead:

Image result for monty python black knight

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