Gwynne Shotwell lecture at Stanford 11 Oct 2017

[IainMcClatchie]

I posted the following question: "The Shuttle heat shield required extensive maintenance due to water contamination. How will the PICA-X shield on BFS avoid this problem?"

One of the things that prevented the Shuttle from turning around quickly was drying and replacing tiles.  They'd get wet just sitting out in the weather waiting for launch.

PICA-X on the Dragon is enclosed between the capsule and the Trunk, and can be protected from atmospheric moisture.  The PICA-X on BFS cannot.  Is the stuff water repellant?

An Inconel shield on the bottom of the BFR should handle moisture well.  I have no doubt they can turn that around quickly.

[Port]

inconel is a metal which conducts heat exceptionally well, also it is not ablative. it's literally a "shield" (in a medieval sense) which will not work in any way, shape or form.

also pica-X and the ceramic tiles of the space shuttle have very little in common except their purpose. Space shuttle tiles are made up mostly of air and silica-fibres (i think this is the reason for their hydrophilicity) while pica is a carbon fibre matrix impregnated with phenol-resin. the resin should stop water mostly, but i'm no specialist in heatshield materials, the info i presented was literally extracted from the corresponding wikipedia articles in 2 minutes time.. you might want to consider checking your questions for trivial answers before asking
https://en.wikipedia.org/wiki/Atmospheric_entry#PICA-X
https://en.wikipedia.org/wiki/Space_Shuttle_thermal_protection_system#High-temperature_reusable_surface_insulation_.28HRSI.29

[Robotbeat]

Ask about ISRU! See if prototypes for Mining droids, Sabatier reactor equipment, etc has been made.

[oiorionsbelt]

Ask about ISRU! See if prototypes for Mining droids, Sabatier reactor equipment, etc has been made.

Yes, ask questions about Mars surface activity.
 Unfurling/setting up solar arrays. What does that look like?

[envy887]

inconel is a metal which conducts heat exceptionally well, also it is not ablative. it's literally a "shield" (in a medieval sense) which will not work in any way, shape or form.

Iain suggested Inconel for the booster (BFR), not the ship (BFS). That should work fine; the Block 5 F9 booster is supposed to have Inconel shields around its base.

[Helodriver]

On site, front row. T-52 minutes.

[TripD]

I am so spoiled now.  Really wish this was live streamed.

[Flying Beaver]

Is it just me or have the questions been reset. Only seeing ones posted within the past half hour... And non of Helodriver's.

https://app.sli.do/event/idqu1pqo/ask

[Michael Baylor]

Is it just me or have the questions been reset. Only seeing ones posted within the past half hour... And non of Helodriver's.

https://app.sli.do/event/idqu1pqo/ask

It's not just you, and most of the new ones are complete crap. Hopefully, these aren't the ones they gave her. If they are it's a big opportunity wasted.

[meberbs]

Is it just me or have the questions been reset. Only seeing ones posted within the past half hour... And non of Helodriver's.

https://app.sli.do/event/idqu1pqo/ask

It's not just you, and most of the new ones are complete crap. Hopefully, these aren't the ones they gave her. If they are it's a big opportunity wasted.

Looks like they asked good ones. No recording was allowed, but some people have posted their notes on reddit. In addition to the OP, Sticklefront and ergzay have detailed comments with their notes. Each has something that the others don't.

Hopefully when Helodriver has time, he can add anything else that they missed, or clarify on some points that the others seem to have understood in different ways.

[FutureSpaceTourist]

@SpaceX Prez @GwynneShotwell & @DFJSteve having fun onstage tonight talking all things Mars and #BFR (she clarified the F is for Falcon).

https://twitter.com/glydstone/status/918345583097556992

[dror]

Is it just me or have the questions been reset. Only seeing ones posted within the past half hour... And non of Helodriver's.

https://app.sli.do/event/idqu1pqo/ask

It's not just you, and most of the new ones are complete crap. Hopefully, these aren't the ones they gave her. If they are it's a big opportunity wasted.

Looks like they asked good ones. No recording was allowed, but some people have posted their notes on reddit. In addition to the OP, Sticklefront and ergzay have detailed comments with their notes. Each has something that the others don't.

Hopefully when Helodriver has time, he can add anything else that they missed, or clarify on some points that the others seem to have understood in different ways.

Other than reaffirming previous data, the only real 'news' seems to be that they are looking to build a new factory for BFR in LA on the water.

[vaporcobra]

Ehhh, check again. There was a ton of very new information. Vague speculation on NSF does not equal straight-from-Shotwell info.

General sampling:
-larger Raptor currently under construction
-hope is for manufacturing facilities at all BFR launch pads
-confirmed that Boca is explicitly for BFR
-suggested that SpaceX could fund BFR and Starlink simultaneously, albeit with a bit longer timeline
-reiterated December for FH and possibly LC-40
-BFR P2P wouldn't be economical for short trips, but could be cheaper than economy flights for long trips
-fairings to be regularly reused by H2 2018
-S2 recovery will not actually attempt recovery, more just explore the orbital reentry regime
-confident that SpaceX can make carbon composite prop tanks operational, BFR could be ready before the stuff needed to live on Mars
-SpaceX will build the Martian infrastructure if they have to, would prefer other companies to start work on it
-not likely a coincidence that Musk started TBC, tunnels will be crucial until domes and terraforming on Mars

And much more.

[woods170]

@SpaceX Prez @GwynneShotwell & @DFJSteve having fun onstage tonight talking all things Mars and #BFR (she clarified the F is for Falcon).

https://twitter.com/glydstone/status/918345583097556992

Emphasis mine.
That has been known since last year, courtesy of the Gallery section of SpaceX.com

I've never understood why folks designated some other F-word to the letter 'F'.

[jpo234]

-larger Raptor currently under construction

It seems unclear what she meant here. It could either mean a physically larger engine or a engine with upscaled capabilities with the same physical size.

[woods170]

Ehhh, check again. There was a ton of very new information. Vague speculation on NSF does not equal straight-from-Shotwell info.

General sampling:
-larger Raptor currently under construction

There is disagreement in the Reddit thread about Gwynne actually saying that. Larger, in the context of Raptor, is likely to be interpreted as scaling up the thrust levels of Raptor.

[jebbo]

I was struck by the following from the reddit thread:

SpaceX is focused on the transportation part of the Mars problem, but people need somewhere to go once they arrive. I don't think it's an accident that Elon started the Boring Company, tunnels will be very important in the first steps of living on Mars, before we build domes and terraform. We want other companies to start thinking about it and working on it, but we'll do it if we have to. I think the BFR might be ready before these other components of actually living on Mars.

and

Harder than the rocket, though, will be where people are going to live, what will life be like, what will they do there?

Feels like these could significantly delay things, regardless of BFR progress.

--- Tony

[docmordrid]

@SpaceX Prez @GwynneShotwell & @DFJSteve having fun onstage tonight talking all things Mars and #BFR (she clarified the F is for Falcon).

https://twitter.com/glydstone/status/918345583097556992

Emphasis mine.
>
I've never understood why folks designated some other F-word to the letter 'F'.

Because Musk has used Big F....g Rocket/Spaceship numerous times, fleshing it out in a Dec. 2015 GQ interview. Until they give it an official name....
..

https://www.gq.com/story/elon-musk-mars-spacex-tesla-interview

[jpo234]

I was struck by the following from the reddit thread:

SpaceX is focused on the transportation part of the Mars problem, but people need somewhere to go once they arrive. I don't think it's an accident that Elon started the Boring Company, tunnels will be very important in the first steps of living on Mars, before we build domes and terraform. We want other companies to start thinking about it and working on it, but we'll do it if we have to. I think the BFR might be ready before these other components of actually living on Mars.

and

Harder than the rocket, though, will be where people are going to live, what will life be like, what will they do there?

Feels like these could significantly delay things, regardless of BFR progress.

--- Tony

These problems won't delay the exploration phase. This is about the actual city/colony.

[Helodriver]

The questions app was indeed reset right before the event started and the questions that were submitted by the audience during the event tended toward the simplistic type as in who goes to Mars first. Steve Jurvetson did have a printed list of questions which included mine and he worked a couple into the general questioning. I will say that in that in general there was a good amount of new information released by Gwen particularly about BFR construction location and launch sites that we had not heard before. BFR gets its own LA harbor factory and launches from Boca Chica among other places.