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32 minutes ago, Barzon said:

Per Anatoly Zak, Dragon XL is 13t. 

So 2 short buses it is ;)

 

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On 3/15/2021 at 3:27 AM, mikegarrison said:

How ironic is it that they always have trouble maintaining a communication link to their drone ship during landing? I mean, the whole Starlink thing and all....

I wonder it too. Otherwise they put so much effort to videos and all kind of PR work but video system of ship is from cheap store. I am quite sure that installing a proper video link would not cost too much compared to total PR expenses. But they certainly have too much small things to do and too little workers as all companies nowadays. Videos work, everyone see does it success or crash, and they prefer other problems.

 

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17 minutes ago, Hannu2 said:

I wonder it too. Otherwise they put so much effort to videos and all kind of PR work but video system of ship is from cheap store. I am quite sure that installing a proper video link would not cost too much compared to total PR expenses. But they certainly have too much small things to do and too little workers as all companies nowadays. Videos work, everyone see does it success or crash, and they prefer other problems.

 

As I understand one problem is the plasma from the rocket flame. The second is the vibration and blast from the landing shaking the barge and the antenna. 
Last they don't need good feed of the landing, its an fanservice, yes its nice for the recovery team to know the state of the rocket but that is all. 

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4 hours ago, magnemoe said:

As I understand one problem is the plasma from the rocket flame. The second is the vibration and blast from the landing shaking the barge and the antenna. 
Last they don't need good feed of the landing, its an fanservice, yes its nice for the recovery team to know the state of the rocket but that is all. 

Indeed, the huge amount of shaking generated by the downward end of a rocket is enough to disrupt even the most robust antennas. And they are still able to get more useful telemetry data at lower bandwidth throughout the flight.

Edited by cubinator
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You ever used the Saturn V to fling a block into orbit?

https://spacenews.com/spacex-bid-on-launch-of-nasa-cubesat-mission/

Someone pointed this out elsewhere, but:

Quote

SpaceX’s proposed price was also “somewhat higher” than Astra’s bid.

And

Quote

[Context, Virgin Orbit was eliminated] The competition came down to Astra and Rocket Lab, whose proposal had several strengths, but also a “significantly higher” price than Astra.

Did SpaceX bid Starship at a lower price than Electron?

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21 minutes ago, Spaceception said:

You ever used the Saturn V to fling a block into orbit?

https://spacenews.com/spacex-bid-on-launch-of-nasa-cubesat-mission/

Someone pointed this out elsewhere, but:

And

Did SpaceX bid Starship at a lower price than Electron?

Thanks for the link.

The article raises the interesting possibility that SpaceX bid SSTO Starship (no Super Heavy) for a tiny launch of a cubesat cluster.

It certainly seems like an Elon thing to do, and Starship probably has the dV to reach orbit, if not return. It’s just that 3 Raptors don’t have enough thrust to lift full tanks without RVacs helping out, especially without a semi-steep trajectory from Super Heavy.

If they went ahead and solved this by adding 3-4 more SL engines, it could prove an interesting test with orbital operations and high-velocity reentry, though I wouldn’t expect them to have enough propellant to land, instead ditching the vehicle in the ocean somewhere.

Given that Super Heavy is taking a while (as expected) and Raptor production is (as far as we can tell) still to low to supply an orbital booster, I can see an anxious and impatient Elon deciding to just throw caution and patience to the wind and just give orbit a go.

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2 minutes ago, Clamp-o-Tron said:

It certainly seems like an Elon thing to do, and Starship probably has the dV to reach orbit, if not return. It’s just that 3 Raptors don’t have enough thrust to lift full tanks without RVacs helping out, especially without a semi-steep trajectory from Super Heavy.

They could add the engines and then stretch the fuel tanks.

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7 minutes ago, Clamp-o-Tron said:

If they went ahead and solved this by adding 3-4 more SL engines, it could prove an interesting test with orbital operations and high-velocity reentry, though I wouldn’t expect them to have enough propellant to land, instead ditching the vehicle in the ocean somewhere.

 

4 minutes ago, GuessingEveryDay said:

They could add the engines and then stretch the fuel tanks.

I would be intrigued to see an SSTO starship for tiny payloads....

Spoiler

Maybe they could make an Aerospike Raptor while they're at it lol.

 

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30 minutes ago, Clamp-o-Tron said:

Given that Super Heavy is taking a while (as expected) and Raptor production is (as far as we can tell) still to low to supply an orbital booster, I can see an anxious and impatient Elon deciding to just throw caution and patience to the wind and just give orbit a go.

Starship can't be reused if in SSTO mode. And this contract is something like a year away, while SpaceX seems to be specifically aiming for orbit by July. Which I think is a more reasonable prediction than this time last year when they vaguely predicted the end of 2020, while they were still dealing with cryo issues, Raptor was less developed, and only Starhopper had been flown. At this point, they're flying full scale prototypes every month or so, and finally have a couple boosters on the way.

Raptor production seems okay. If last summer's tweets about its development are any indicator, it looked like they were making 10 Raptors a month. This attempt to orbit is a bit more than 3 months away, and might slip out to fall anyway (either because of hardware issues, or general testing delays), so between that and their current stockpile (if needed), it should be enough.

Edited by Spaceception
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13 minutes ago, RCgothic said:

Anyone got any clue what this might be?

Maybe a rig to help with the construction of the launchpad. They still need some sort of ring on top of the six legs, dont they? It could be to cast concrete on there.

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1 hour ago, Spaceception said:

Starship can't be reused if in SSTO mode. And this contract is something like a year away, while SpaceX seems to be specifically aiming for orbit by July. Which I think is a more reasonable prediction than this time last year when they vaguely predicted the end of 2020, while they were still dealing with cryo issues, Raptor was less developed, and only Starhopper had been flown. At this point, they're flying full scale prototypes every month or so, and finally have a couple boosters on the way.

Raptor production seems okay. If last summer's tweets about its development are any indicator, it looked like they were making 10 Raptors a month, this attempt to orbit is a bit more than 3 months away, and might slip out to fall anyway (either because of hardware issues, or general testing delays), so between that and their current stockpile (if needed), it should be enough.

This, superheavy is not that hard, yes they need to get the engines not shaking each other apart and stuff like that but they probably overbuild the first versions. 
Landing it should be one of the easiest part, no flipping its basically and larger falcon 9 first stage. 
They figured out why they had problems with the engines. the flip stirred the header thanks dropping pressure and creating bobbles in the fuel. 
You can test this without an rocket, just flip and shake an header tank. as I understand the baffles helped creating bubbles. 

The real challenge is probably reentry. 

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Official SpaceX SN10 recap video is up:

Plenty of new views, and we get to see more of that shot (yes!), but they didn't acknowledge it blowing up afterwards. I guess that wasn't part of the flight.

Edited by RyanRising
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7 hours ago, RyanRising said:

but they didn't acknowledge it blowing up afterwards. I guess that wasn't part of the flight.

They did acknowledge it on their website:

"As if the flight test was not exciting enough, SN10 experienced a rapid unscheduled disassembly shortly after landing."

https://www.spacex.com/vehicles/starship/

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1 hour ago, RealKerbal3x said:

They did acknowledge it on their website:

"As if the flight test was not exciting enough, SN10 experienced a rapid unscheduled disassembly shortly after landing."

https://www.spacex.com/vehicles/starship/

I know, I meant in the video I linked. Surely SpaceX has some up close & personal footage of that kaboom. I guess they’re saving it for the eventual “How not to Fly a Mars Rocket” (or your preferred title) montage that I really hope is going to show up eventually.

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                                                                                                                                                                                       (A post in Q&A thread reminded the old idea)

Phase A.

1.
Take Crew Dragon, make it uncrewed, remove/shrink the pressurized compartment, and increase fuel tanks instead. 
Call it Tug Dragon.

2.
Take the Dragon XL cargo compartment
Put it under the Tug Dragon capsule instead of trunk.
Attach a CBM berthing adaptor to its lower end.

3.
Launch this to ISS or LOP-G.
Self-dock with the Dragon IDSS port.

4.
With Canadarm take the XL Cargo Trunk, detach it from Tug Dragon.
Berth to a CBM port of the station.

5. 
Return the Tug Dragon to the Earth, prepare to the next flight.

6.
Unload goods from the berthed XL Cargo Trunk, fill it with bads, unberth and send it away with solid boosters.

***

Phase B.

1.
As the Tug Dragon and the XL Cargo Trunk always have same dimensions, put a Lyappa-style grappling fixture  on the XL Dragon Boxcar.

2.
Instead of manual detaching of the XL Dragon Boxcar with Canadarm, make a simplified big Lyappa matching the Tug/Trunk size and the station CBM port position.
Unlike Lyappa, put it on the station, not on the vessel.

3.
When Tug Dragon has docked, unfold/extend the Big Lyappa, grab the grappling fixture on the XL Dragon Boxcar hull, detach from Tug Dragon and berth to the CBM without manual operations, robotically.

4.
Have a Spacelab-derived logistics module of the station with axial IDSS port, four radial CBM ports, and two BigLyappas to automatically reposition the brought XL Dragon Boxcars from the docked Tug Dragon to any of the CBM radial ports.

***

Phase C.

As all berthed Trunks and the station are connected with same 1.25-wide CBM-compatible hatches, make the automatic logistics system.

1.
Put a coaxial wheel between the radial ports.
Put radially an extendable railway truss on it (like the one they actually use to move cargos through these hatches).
Put a grappling carriage on the rails.

2.
When the XL Dragon Boxcar is berthed, rotate the wheel towards this hatch.
Radially extend the railway truss attached to the wheel, to let it get through the hatch into the XL Dragon Boxcar.

3.
Automatically position the grappling carriage on the rails, take a cargo container from required place in the rack, bring it into the station module.
Automatically grab it with another carriage on the fixed axial railway and move this way to another part of the station, to automatically put it in the rack.

4.
Retract the extendable railway.

So, there is an uncrewed Starship-derived dry workshop orbitatl station with automatical Tug Dragon supply ship.

 

***

Phase D.

Use the same Tug Dragon with any other payload.
Including the Crew Dragon (launch it overturned in this case).

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11 hours ago, RyanRising said:

I know, I meant in the video I linked. Surely SpaceX has some up close & personal footage of that kaboom. I guess they’re saving it for the eventual “How not to Fly a Mars Rocket” (or your preferred title) montage that I really hope is going to show up eventually.

If I had to guess when such a montage appears, it probably will be after the full stack of Starship was tested successfully. As I imagine they will have A LOT more content by then :wink:

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