SpaceX F9 : SES-10 with reuse of CRS-8 Booster SN/1021 : 2017-03-30 : DISCUSSION

[meekGee]

Irene Klotz: Do you have other costumers that weren't as brave as SES that are now signed up?  What is life-limiting factor?

Musk: NASA has been supportive.  Commercial, SES has been most supportive.  Next thing is how to achieve rapid reuse without major hardware changeouts.  Aspirations of zero hardware changes and 24hrs reflight.

And how many pages of useless argument whether the goal is "24 hours reflight" or "24 hours done with refurb"?

People assuming that you can't refly in 24 hours because other processes today take too long - a classic "it can't be done since it isn't currently done".

I guess if the stage can be ready to go in 24 hours, other processes will have to catch up so they DON'T remain the bottleneck.

And even if they don't reach the "aspiration" and it becomes 48 hours or even 72 - still enables 1 flight per day with a set of three boosters.

[ZachS09]

Fairing recovered!?!  Woah!

There is no way that just happened.

I was expecting the fairings not to make it on the first try.

[CameronD]

Marcia Dunn: Will you refly this booster?  Next flight of reuse booster.

Musk:  Several reflights scheduled for later this year. Might fly as many as 6 reflights this year. FH two side boosters are being reflown. That will be interesting mission on FH... hopefully in good direction.  This core will have historic value.  Seeing if Cape might like to have it as something to remember the moment.  Present it as gift to cape

Looking forward to a F9 in the KSCVC Rocket Garden then... maybe! Certainly would look cool next to the Redstone, Titan, Saturn IB, et cetera.

But it would be the only rocket in the collection to have actually launched - and made it back.  Technically, that would upstage the others don't you think?  (pun intended)

I'm looking forward to a rocket boneyard somewhere.. where old boosters, flown too many times, go to die.

[pstephens]

Musk:  Upper stage reuse is next.

Hit the 2 minute "like" throttle.

[TrevorMonty]

Thought they had shelved 2nd stage reuse for F9. Looks like is back on the todo list. 

[cppetrie]

Thought they had shelved 2nd stage reuse for F9. Looks like is back on the todo list.

We only have what has been posted by CG, and that doesn't indicate reusable 2nd stage for F9 but just that it is next on the list of capabilities to develop to achieve their ultimate goal.

[inonepiece]

Musk:  Upper stage reuse is next.

Hit the 2 minute "like" throttle.

Elon's press conferences are not designed for 2 minute like throttles.

[Navier–Stokes]

Thought they had shelved 2nd stage reuse for F9. Looks like is back on the todo list.

We only have what has been posted by CG, and that doesn't indicate reusable 2nd stage for F9 but just that it is next on the list of capabilities to develop to achieve their ultimate goal.

Some more context in Jeff Foust's tweet:

Musk adds it might “fun to try a Hail Mary” and recover an upper stage.

[AC in NC]

Have I lost perspective on time or are we at just over 15 months from 1st landing to Reuse and Landing?

Was it not April last year?

I was referring to the Dec 21, 2015 LZ-1 1st Recovered Stage.

BR) 2015-12-21, Successful landing at LZ1[61]
BR) 2016-04-08, Successful landing at OCISLY [71]

[CameronD]

Musk: New design coming for Grid Fin.  Will be largest titanium forging in the world.  Current Grid Fin is aluminum and gets so hot it lights on fire... which isn't good for reuse.

I'm a little surprised to hear they wouldn't 3D-Print it.. wouldn't that be cheaper??

http://3d-printing-titanium.com/

[Kabloona]

Quote from presser:

Brendan Bryne (NPR): Anything you're worried about?

Musk: Looked a telemtry up and down.  It all looks really good.  Eyeballing it, other things to address to replace TPS on grid fins and base heat shield and repaint where needed.

Yes, I noticed on the webcast that the grid fin on the right side was getting its TPS (almost?) entirely melted off and deposited on the camera lens near the end of the entry video. The grid fin/TPS appeared to be glowing as it ablated off. Extra crispy.

[Robotbeat]

Musk: New design coming for Grid Fin.  Will be largest titanium forging in the world.  Current Grid Fin is aluminum and gets so hot it lights on fire... which isn't good for reuse.

I'm a little surprised to hear they wouldn't 3D-Print it.. wouldn't that be cheaper??

http://3d-printing-titanium.com/

Probably no titanium 3D printer big enough. Anyway, large metal 3D printing is expensive, has inferior surface finish, and produces lower strength than a forging. Forging is better especially if you'll be making several copies (SpaceX will make at least 100 of them).

[CameronD]

Musk: New design coming for Grid Fin.  Will be largest titanium forging in the world.  Current Grid Fin is aluminum and gets so hot it lights on fire... which isn't good for reuse.

I'm a little surprised to hear they wouldn't 3D-Print it.. wouldn't that be cheaper??

http://3d-printing-titanium.com/

Probably no titanium 3D printer big enough. Anyway, large metal 3D printing is expensive, has inferior surface finish, and produces lower strength than a forging. Forging is better especially if you'll be making several copies (SpaceX will make at least 100 of them).

Interesting info.. thanks for the explanation.

[meekGee]

Thought they had shelved 2nd stage reuse for F9. Looks like is back on the todo list.

There is little of free will in an Engineer.

[toren]

The skeptics aren't the only ones who can move the goal posts...

[Lars-J]

From the updates thread:

Musk: New design coming for Grid Fin.  Will be largest titanium forging in the world.  Current Grid Fin is aluminum and gets so hot it lights on fire... which isn't good for reuse.

Yeah, he's not kidding... The grid fin looked ready to melt!  (although that was likely just the outer layer)

EDIT: The stage must be re-entering at an angle to affect the grid fins so differently.

[meekGee]

From the updates thread:

Musk: New design coming for Grid Fin.  Will be largest titanium forging in the world.  Current Grid Fin is aluminum and gets so hot it lights on fire... which isn't good for reuse.

Yeah, he's not kidding... The grid fin looked ready to melt!  (although that was likely just the outer layer)

EDIT: The stage must be re-entering at an angle to affect the grid fins so differently.

Yes - at an angle to the velocity vector

[Kabloona]

EDIT: The stage must be re-entering at an angle to affect the grid fins so differently.

Yes, we've seen that asymmetry on photos of recovered stages, where the white paint on the interstage above one of the grid fins has been blasted off by the TPS coming off the grid fin, but the white paint remains intact on the opposite side of the interstage.

[CameronD]

Hafta admit, it was very cool watching it smoulder gently away in the sunlight... looked a bit like toasting a breakfast waffle with a blowtorch.

[Herb Schaltegger]

From the updates thread:

Musk: New design coming for Grid Fin.  Will be largest titanium forging in the world.  Current Grid Fin is aluminum and gets so hot it lights on fire... which isn't good for reuse.

Yeah, he's not kidding... The grid fin looked ready to melt!  (although that was likely just the outer layer)

EDIT: The stage must be re-entering at an angle to affect the grid fins so differently.

Yes - at an angle to the velocity vector

Indeed. As someone has calculated pretty well in other threads, an F9 stage has a fairly decent L/D ratio, given adequate attitude control to modulate angle of attack. With the use of grid fins, it's even better. Not only do they provide excellent control authority all the way from hypersonic to high subsonic flight regimes, they also contribute a good deal to the overall lift of the vehicle.