SpaceX Falcon 9 - EchoStar 23 - March 16, 2017 - DISCUSSION

[Raul]

It is probably standart SSL 1300 - about 5500kg, so I guess, that they will use 1121-EX-ST-2016 originally for Amos-6 mission - planned ASDS position could be identical and this application wasn't used. For example F9-025 and F9-026 also had identical droneship position.

[jjyach]

https://twitter.com/elonmusk/status/822926184719609856

Looks like it's going to be expendable

edit/gongora: 
Question on Twitter: "@elonmusk Next SpaceX flight (Echostar) has v heavy GTO payload (5500kg) Will Falcon fly expendable, or try low-margin droneship landing?"
Elon's Answer: "@gdoehne Expendable. Future flights will go on Falcon Heavy or the upgraded Falcon 9."

[mme]

https://twitter.com/elonmusk/status/822926184719609856

Looks like it's going to be expendable

@gdoehne Expendable. Future flights will go on Falcon Heavy or the upgraded Falcon 9.

So now we also know that either the "safer" propellent loading reduced performance or Block 5 is getting another performance boost as well as reusability improvements.  Or both.

[IanThePineapple]

Hopefully Block 5 will allow for no expendable flights needed.

[gongora]

So now we also know that either the "safer" propellent loading reduced performance or Block 5 is getting another performance boost as well as reusability improvements.  Or both.

Sounds like the safer propellant loading might have cost them just enough margin to make this mass an expendable launch, since the 5300kg sat coming up next seems to have an ASDS landing planned.  Wonder what will happen with the 5400kg SES-11/EchoStar 105 launch.  (I don't think we even know at this point if they're using block 3 or block 4?  If still on block 3 then there could still be performance upgrade before block 5?)

[gongora]

Hopefully Block 5 will allow for no expendable flights needed.

FH needed for no expendable flights.  Not sure even Block 5 would help with the >6 ton satellites.

[yokem55]

In any case, they have more cores on their hands than they know what to do with. So instead of a lower performance GTO and a risky ASDS landing (don't want to falcon punch it again) they can get the customer to a higher transfer orbit, not have to deal with a damaged drone ship or yet another marginally reusable core to store.

[Robotbeat]

In any case, they have more cores on their hands than they know what to do with. So instead of a lower performance GTO and a risky ASDS landing (don't want to falcon punch it again) they can get the customer to a higher transfer orbit, not have to deal with a damaged drone ship or yet another marginally reusable core to store.

[ChrisC]

https://twitter.com/elonmusk/status/822926184719609856

Looks like it's going to be expendable

Question on Twitter: "@elonmusk Next SpaceX flight (Echostar) has v heavy GTO payload (5500kg) Will Falcon fly expendable, or try low-margin droneship landing?"
Elon's Answer: "@gdoehne Expendable. Future flights will go on Falcon Heavy or the upgraded Falcon 9."

To clarify, since "expendable" means they will not try to land the S1 core anywhere, they won't even bother putting legs or grid fins on it.  I was not aware of this until recently.  (source)

[meekGee]

Breaks your heart, doesn't it... 

[Jarnis]

It will look very strange to see Falcon 9 go up without any intention of coming back.

Bit like those dinosaur rockets from ULA

[manoweb]

Well to some extent this expendable launch would have been a good candidate for a reused booster

[Jos]

https://twitter.com/elonmusk/status/822926184719609856

Looks like it's going to be expendable

Question on Twitter: "@elonmusk Next SpaceX flight (Echostar) has v heavy GTO payload (5500kg) Will Falcon fly expendable, or try low-margin droneship landing?"
Elon's Answer: "@gdoehne Expendable. Future flights will go on Falcon Heavy or the upgraded Falcon 9."

To clarify, since "expendable" means they will not try to land the S1 core anywhere, they won't even bother putting legs or grid fins on it.  I was not aware of this until recently.  (source)

Echostar 23 is about the same weight as Amos 6 (5500 kg). Was Amos 6 also supposed to be expendable, or is this due to lower performance caused by the new propellant loading procedures?

[Earendil]

IMO not only loss of performance due to loading procedures, but also from reduced LOX volume in S2 (it has one more COPV, so less LOX).
I can't do the math on how much less is 1 COPV worth of LOX volume in dV, but I think it might have more impact than the overall slightly warmer LOX.

(Layman's thinking here..)

[Nomadd]

 They do have a history of providing better a better GTO to make up for delays and as mentioned, recovering the last one of this block might be of low value anyhow.

[Danny452]

IMO not only loss of performance due to loading procedures, but also from reduced LOX volume in S2 (it has one more COPV, so less LOX).
I can't do the math on how much less is 1 COPV worth of LOX volume in dV, but I think it might have more impact than the overall slightly warmer LOX.

(Layman's thinking here..)

Presumably the number of COPVs in the first stage LOX tanks has also increased causing reduced LOX volume there.  Does anyone know how many more COPVs have been placed in the first stage LOX tank?  And for context, the total number of COPVs now in that tank?  Also, are all the COPVs the same size?

[wannamoonbase]

Breaks your heart, doesn't it... 

I don't think so, I think it's a great opportunity to see what this bird can do.  Stripping the reusability weight and maybe run to depletion.  Give the bird a good ride.

Agreed, this would be a good flight for a bird that's already flown once.

[meekGee]

Breaks your heart, doesn't it... 

I don't think so, I think it's a great opportunity to see what this bird can do.  Stripping the reusability weight and maybe run to depletion.  Give the bird a good ride.

Agreed, this would be a good flight for a bird that's already flown once.

Like watching an airplane take off and the discard it's landing gear, "to see what it can really do".

It can't really do it, since it can't land.  It's a suicide mission.

Or sending an airstrike beyond its flyback range (post Perl Harbor).... It's not their "real range" in any reasonable sense of the word...

A matter of whether you think if launch vehicles as inherently reusable or not. This particular F9 is going to take the big one for the team.

[Patchouli]

Well to some extent this expendable launch would have been a good candidate for a reused booster

It's an expensive payload so it's probably best to be conservative.

IMO not only loss of performance due to loading procedures, but also from reduced LOX volume in S2 (it has one more COPV, so less LOX).
I can't do the math on how much less is 1 COPV worth of LOX volume in dV, but I think it might have more impact than the overall slightly warmer LOX.

(Layman's thinking here..)

Also the mass increase of the extra COPV in S2 which would directly impact the payload.
When you think about that both stages in F9 have an ISP less then 350 it's pretty impressive they can do GTO payloads that size at all without resorting to adding a third stage.

[Lar]

Well to some extent this expendable launch would have been a good candidate for a reused booster

I think they want the reused ones back at first so they can examine them after a second flight... maybe later on though if this ever arises again.

Thanks for taking one for the team... we hardly knew you.