News Changes to the SpaceX BFR rocket.

[RGClark]

Elon on his twitter account said SpaceX now wants to move to metals for the tanks and structures of the BFR:

https://www.nextbigfuture.com/2018/...hip-design-is-metal-tanks-and-structures.html

He said the move was "counter-intuitive". Perhaps this is because of the prevailing view carbon composites had to be used to save weight. But actually some new metal alloys are better on strength-to-weight than carbon composites:

https://exoscientist.blogspot.com/2018/06/darpas-spaceplane-x-33-version-page-2.html

Elon described the metal to be used as "heavy" but "extremely strong". This suggests either high strength titanium or steel alloys rather than the aluminum ones.

Also, there is speculation that SpaceX intends to use the tufroc heat shield material used on the X-37 for the BFR heat shield because of an announced partnership with NASA on the material:

https://www.teslarati.com/spacex-new-bfr-heat-shield-advancements-nasa-assistance/

Bob Clark

 

[RGClark]

Elon has announced the metal to be used on the BFR will be a specialty high strength stainless steel alloy:

https://www.teslarati.com/spacex-ceo-elon-musk-starship-bfs-hop-tests-early-2019/


Bob Clark

 

[MaverickSawyer]

Hmph. The rate at which Elon keeps changing the design makes me extraordinarily skeptical of anything he says until such time as they commit to production facilities.

 

[Thunder Chicken]

Not sure if this was posted elsewhere, but this photo seems to show what appeared to be a silo is actually the BFS Grasshopper and a nosecone in the background.



https://www.teslarati.com/spacex-ceo-elon-musk-starship-bfs-hop-tests-early-2019/

 

[4throck]

Seeing hardware is always good, and the more it has in common with Falcon, the better.

 

[mahdavi3d]

 

[RGClark]

SpaceX's Shiny Stainless Steel Starship - YouTube​

Nice discussion there of the fact steel would be better for thermal protection. But I’m surprised he didn’t mention that some newer metal alloys simply are better at strength-to-weight than carbon composite.

That Elon described the choice as “counter-intuitive”, and said the metal to be used was “extremely strong” suggests this is the case. In other words, the high strength metal was selected to reduce the weight.


Bob Clark

 

[Pipcard]

[ame="https://twitter.com/elonmusk/status/1083568315656822784"]Elon Musk on Twitter: "This is for suborbital VTOL tests. Orbital version is taller, has thicker skins (won’t wrinkle) & a smoothly curving nose section."[/ame]

 

[4throck]

Heinlein style rocket

 

[MaverickSawyer]

Well, we are getting closer to an SSTO as God and Heinlein intended it, soooo...

 

[mahdavi3d]

 

[Urwumpe]

Maybe interesting for some here: You can watch the test site of SpaceX on a livestream.

 

[Urwumpe]

Looks like a first small test of the Hopper is planned this week:

!FDC 9/1046 ZHU TX..AIRSPACE BROWNSVILLE, TX..TEMPORARY FLIGHT
RESTRICTIONS WI AN AREA DEFINED AS 1.1 NM RADIUS OF 255916N/0971112W
(BROWNSVILLE VORTAC BRO061010.9) SFC-1000FT AGL TO PROVIDE A SAFE
ENVIROMENT FOR ROCKET LAUNCH AND RECOVERY PURSUANT TO 14 CFR SECTION
91.143. PURSUANT TO 14 CFR SECTION 91.137(A)(3) TEMPORARY FLIGHT
RESTRICTIONS ARE IN EFFECT. SPACEX ARE AUTHORIZED IN THE AIRSPACE.
SPACEX TELEPHONE 202-649-2636 IS IN CHARGE OF THE OPERATION. HOUSTON
/ZHU/ ARTCC TELEPHONE 281-230-5560 IS THE FAA COORDINATION FACILITY.
  EFFECTIVE:
     1903251400 UTC UNTIL 1903252300 UTC
     1903261400 UTC UNTIL 1903262300 UTC
     1903271400 UTC UNTIL 1903272300 UTC

 

[mahdavi3d]

=================

 

[Thunder Chicken]

[ame="https://youtu.be/Ec-8A5k16Ak?t=22"]Where was the kaboom?[/ame] :lol:

 

[mahdavi3d]

 

[GLS]

Looks like things are going to happen today...

 

[BrianJ]

Been waiting long enough to see this crazy thing fly - Go Starship Sn.8! Good luck SpaceX!

 

[BrianJ]

Ah well. Maybe next time.

 

[Thunder Chicken]

The animation of what they want to happen is insane.