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I was looking at the launch manifest over on r/spacex, and noticed that ArabSat 6A, which is slated to be launched on Falcon Heavy in January, only masses 6 tons. The launch of Telstar 19V shows that this figure is well within F9 Block 5's payload capacity. So, does anyone know why ArabSat is still being launched on Falcon Heavy? I seem to remember hearing that Telstar 19V was deposited somewhere short of a proper GTO trajectory because of its mass. Is that it?

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8 minutes ago, IncongruousGoat said:

I was looking at the launch manifest over on r/spacex, and noticed that ArabSat 6A, which is slated to be launched on Falcon Heavy in January, only masses 6 tons. The launch of Telstar 19V shows that this figure is well within F9 Block 5's payload capacity. So, does anyone know why ArabSat is still being launched on Falcon Heavy? I seem to remember hearing that Telstar 19V was deposited somewhere short of a proper GTO trajectory because of its mass. Is that it?

It may be a first operational use of the FH’s ability to deliver the sat direct to GSO. Ie, the sat won’t have to circularize on its own, the FH upper will take care of that then go park itself in a lonely orbit. 

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17 hours ago, CatastrophicFailure said:

It may be a first operational use of the FH’s ability to deliver the sat direct to GSO. Ie, the sat won’t have to circularize on its own, the FH upper will take care of that then go park itself in a lonely orbit. 

This would require longer duration for the upper stage, not only does it have to last until the gto circulation but it also has to put itself in a graveyard orbit afterward. Yes its solvable with an larger battery and probably better power management. 

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59 minutes ago, magnemoe said:

This would require longer duration for the upper stage, not only does it have to last until the gto circulation but it also has to put itself in a graveyard orbit afterward. Yes its solvable with an larger battery and probably better power management. 

Didn't the test flight deliberately spend some time hanging around before burning for it's trans-martian orbit deliberately to demonstrate this capability? 

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46 minutes ago, tomf said:

Didn't the test flight deliberately spend some time hanging around before burning for it's trans-martian orbit deliberately to demonstrate this capability? 

Quite so. And deliberately made not one but two passes through the Van Allen belts to demonstrate that the electronics could take it. It wasn’t all for show, it was verifying that the FH could deliver a sat direct to GSO. I think they said that the upper stage lasted for about 24 hours, whether that’s till the batteries died or it moved out of range I’m not sure.  

Edited by CatastrophicFailure
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1 hour ago, CatastrophicFailure said:

Quite so. And deliberately made not one but two passes through the Van Allen belts to demonstrate that the electronics could take it. It wasn’t all for show, it was verifying that the FH could deliver a sat direct to GSO. I think they said that the upper stage lasted for about 24 hours, whether that’s till the batteries died or it moved out of range I’m not sure.  

Van Allen belt is not GSO, it way more hostile, its part why nobody uses ion engines to go from LEO to GSO and outward. You don't want to spend months in the belt it hurt chips and solar panels. 
Spacex don't use space graded chips but depend on redundancy and this is questionable then going into deep space 

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17 minutes ago, magnemoe said:

Van Allen belt is not GSO, it way more hostile, its part why nobody uses ion engines to go from LEO to GSO and outward. You don't want to spend months in the belt it hurt chips and solar panels. 
Spacex don't use space graded chips but depend on redundancy and this is questionable then going into deep space 

Which is why they made not one but two passes, to demonstrate that they can, plus 6+ hours coast time, plus several hours post-TMI... I think you’re missing my point, that all that adds up to a direct GSO delivery once reshuffled. 

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1 hour ago, StrandedonEarth said:

Did they have to make the tanks green? At first glance on mobile the lander looks like it’s stuffed full of kerbals

They would gain all the respect I have to give if the lander, upon landing, spits out a little model of the KerbalX with “Mün or bust” on the side then takes a picture of it. :D

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Crew Dragon is waiting in FL, they had expected a November launch, then December. Wonder how soon they could go, scheduling seems like it should be altered to get a new crew vehicle ready ASAP.

Accelerate the January test flight as much as possible (forget "the paperwork" delaying them), the second Crew Dragon mission can be an ISS crew delivery.

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11 minutes ago, tater said:

CRS-16 has a launch date of Nov 27. I wonder if DM-1 could replace that (with cargo)?

Given that it’s a maiden flight, stuffing it full of cargo might be a non-trivial thing. They’ll have it virtually lined with sensors that need very specific conditions, launch couches(?), etc. Any significant amount of cargo might be a variable they don’t want on a test flight. 

Tho it’s SpaceX, and the two Dragons need different docking ports. So here’s the perfect time for that 24 hour turnaround they’ve been touting, get to look like hero’s too. :D

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I thought it was bringing cargo already, actually, wasn't that always the plan?

None of this would be an issue if substantial commercial crew monies had not been diverted to SLS to prevent further schedule slip.

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22 minutes ago, tater said:

I thought it was bringing cargo already, actually, wasn't that always the plan?

I hadn’t heard anything concrete one way or the other, but just given the nature of the mission, I would think they’d want to eliminate as many potential unknowns as possible. 

Giant cheese wheels in the “snacks” bin aside... -_-

 

23 minutes ago, tater said:

None of this would be an issue if substantial commercial crew monies had not been diverted to SLS to prevent further schedule slip.

Oh, haven’t you heard? That’s been delayed again... due insufficient funds. :D

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8 hours ago, CatastrophicFailure said:

Given that it’s a maiden flight, stuffing it full of cargo might be a non-trivial thing. They’ll have it virtually lined with sensors that need very specific conditions, launch couches(?), etc. Any significant amount of cargo might be a variable they don’t want on a test flight. 

Tho it’s SpaceX, and the two Dragons need different docking ports. So here’s the perfect time for that 24 hour turnaround they’ve been touting, get to look like hero’s too. :D

The first dragon 1 docking test added cargo, I guess mostly bonus food, quality of life stuff and perhaps some spare parts who is nice to have. 
As I understand Soyuz crewed missions don't bring much cargo. Main point is the docked Soyuz has an expire date and the US astronaut was doing an spacewalk. 

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