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I understand it's an approximation.

 

However, given that the average width of a school bus is around 90 inches, that means that the XL has a diameter of 4.57m (!) 

That is almost a meter greater in diameter than a falcon core stage. Although I suppose that the fairings are a greater diameter than that as well. 

 

For mass, we'll take a value of 20,000 kg. for each bus. That puts us at 40,000 kg, or, 44 tons.

What? :huh:

How is this thing going to be launched? Definitely not on Falcon Heavy.....

Obviously my napkin math may be bad, but the figures don't really add up.

FH cannot get 44 tons to the moon. (At least for now)

Perhaps they plan to launch it on SLS???

 

Edited by Spaceman.Spiff
darn units
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The internal diameter of the F9 fairing is 4.6m, so it is certainly less than that.

1 minute ago, Spaceman.Spiff said:

Perhaps they plan to launch it on SLS???

No.

The mass will be substantially lower than 40t.

It'll go on FH.

Not least because SLS could not send a 40t vehicle to TLI, lol.

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6 minutes ago, Spaceman.Spiff said:

I suppose they are thinking of very small school buses :P

A quick google shows US "type B" school buses are ~4500kg, and type C are ~9800kg. Type D are ~9100kg. So 2 are between 9t and ~20t. FH mass to TLI is in the low 20t range.

Edited by tater
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SN11 is getting close to a static fire. EDIT - About 12 minutes or so

And according to them, they're aiming for orbit this summer with SN20 and BN3. https://www.nasaspaceflight.com/2021/03/starship-sn11-spacex-orbital-flight-summer/
Apparently, BN1 won't fly, but will do everything else, and SN18 and 19 will be skipped like SN12-14. If they really do that, they must be confident in most of the systems and hardware at this point.

 

Edited by Spaceception
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4 hours ago, RCgothic said:

Some new Dragon XL art

 

 

Ah, I see they’ve installed KIS to get the nifty cargo crates... -_-

2 hours ago, Ziggy Kerman said:

Yay small? I think it's bout, 28 passengers, just eyeballing.9 to 34 Passengers Mini School Buses for Sale at American Bus Sales

Something something Artemis-SLS-“short bus”... <_<

1 hour ago, sevenperforce said:

Aiming for an orbital flight with SN20 and BN3 by July 1?

Insanity.

But the good kind.

Well, the whole area IS starting to look a bit like CRAAAAAZY ELON’S USED ROCKET SALES!

*no warrantee expressed or implied, some assembly required 

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2 hours ago, Spaceman.Spiff said:

oh geez....

i read my units wrong..... 

Do you want to crash a spacecraft? Because that's how you crash a spacecraft. ;-p

1 hour ago, sevenperforce said:

Aiming for an orbital flight with SN20 and BN3 by July 1?

Insanity.

But the good kind.

Gives them six months' float to beat SLS to orbit. It'll be so so funny if SLS is never the world's most powerful rocket.

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  (moved from SLS)

25 minutes ago, Barzon said:

Are you sure? Everything I've heard is that  Starship expendable can't get anything futher than GTO without refuelling? Although yes a kickstage could probably do the job.

Well, it gets itself, plus ~100-150 tons to LEO. A stripped version might get to a decent elliptical orbit with that same payload... the payload then has enough dv to go literally anywhere.

Clipper/lander version is 15-16t, total.

Payload to LEO of a stripped version... needs no SL raptors. Dunno what it might mass minus all the fins, batteries, tiles, etc. Also no landing props (or rather it can burn them on ascent).

If they made a kick stage with 1 Rvac, and they could get 150t payload to LEO, that Rvac kick stage could give the EC lander ~7.5 km/s (more than enough to get to Saturn (well past what is required for Jupiter)).

Edited by tater
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3 hours ago, tater said:

A quick google shows US "type B" school buses are ~4500kg, and type C are ~9800kg. Type D are ~9100kg. So 2 are between 9t and ~20t. FH mass to TLI is in the low 20t range.

Per Anatoly Zak, Dragon XL is 13t. 

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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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