Author Topic: Gwynne Shotwell lecture at Stanford 11 Oct 2017 (Read 56893 times)

cppetrie · « **Reply #20 on:** 10/08/2017 11:39 pm »

Is the raptor we’ve seen tested at McGregor the same size as what will be on BFR and so just needs uprating as testing proceeds or will it need to be scaled up?

Submitted this as Chris Petrie. Please upvote.
https://app.sli.do/event/idqu1pqo/ask

Robotbeat · « **Reply #21 on:** 10/08/2017 11:54 pm »

Quote from: philw1776 on 10/08/2017 10:52 pm

Gwynne Shotwell you mentioned SpaceX interest in nuclear previously. In flight or planetary surface? Could you elaborate on that?

Is SpaceX considering any long range working interest in fusion propulsion systems such as Princeton Satellite Systems, Inc. Direct Fusion Drive?

We know that engineering resources at SpaceX have assisted Tesla in problem areas. Any details about Tesla/Solar City synergy on Mars surface transport, solar power and storage systems?

I like the first and last ones, but personally I'm generally interested in Surface power and transport whether or not it has anything to do with Tesla.

TomNTex · « **Reply #22 on:** 10/09/2017 03:24 am »

Submitted as Tom :

When will we see the re-launch of a re-used Falcon 9 booster? in other words, the third launch of a single booster? What are the challenges to make that happen?

RocketmanUS · « **Reply #23 on:** 10/09/2017 06:23 am »

1 ) Can the BFS land back on Earth with a 150 t payload? That is can the structure handle this much payload on landing on Earth?

2 ) What is the mass limit of the BFS landing on Earth ( dry mass + unused propellant + payload )?

Edit:
typo, NFS to BFS

Lars-J · « **Reply #24 on:** 10/09/2017 06:47 am »

Quote from: RocketmanUS on 10/09/2017 06:23 am

1 ) Can the BFS land back on Earth with a 150 t payload? That is can the structure handle this much payload on landing on Earth?

2 ) What is the mass limit of the NFS landing on Earth ( dry mass + unused propellant + payload )?

Elon already said that the max landing payload is 50 t. (view 2017 IAC talk again) Please don't ask questions that we already know the answer to, it just limits the amount of new stuff we might learn.

QuantumG · « **Reply #25 on:** 10/09/2017 07:56 am »

Quote from: Lars-J on 10/09/2017 06:47 am

Elon already said that the max landing payload is 50 t. (view 2017 IAC talk again) Please don't ask questions that we already know the answer to, it just limits the amount of new stuff we might learn.

I don't think we appreciate how much of a hard ask that is...

we really need a clearing house for questions, or something. Community intelligence is the reason why we keep coming back here.

darkenfast · « **Reply #26 on:** 10/09/2017 08:21 am »

What will be the first two launch pads that the BFR will fly from?

Edit: Posted as question #66.

speedevil · « **Reply #27 on:** 10/09/2017 12:07 pm »

Quote from: Bynaus on 10/08/2017 07:57 pm

Some of these questions are great, I upvoted many of them. But please don't ask the "airliner" question again. We know the answer to that one. SpaceX will never sell vehicles for others to run.

If they get a dominant enough position in any market, there is the potential for anticompetitive investigations, which can do various things that the company would 'never' choose to do.
(Though while Gwynne may have insight into the strategy for avoiding this, it's really unlikely she's going to spill)

Billium · « **Reply #28 on:** 10/09/2017 06:40 pm »

Can you ask her to confirm the status of land landings at Vandy?

RocketmanUS · « **Reply #29 on:** 10/09/2017 08:17 pm »

Quote from: Lars-J on 10/09/2017 06:47 am

Quote from: RocketmanUS on 10/09/2017 06:23 am
1 ) Can the BFS land back on Earth with a 150 t payload? That is can the structure handle this much payload on landing on Earth?

2 ) What is the mass limit of the BFS landing on Earth ( dry mass + unused propellant + payload )?

Elon already said that the max landing payload is 50 t. (view 2017 IAC talk again) Please don't ask questions that we already know the answer to, it just limits the amount of new stuff we might learn.

#2 is not known , I want to know how much mass BFS can handle landing on Earth. It does not matter were it is coming from but how strong the BFS structural is. Commercial airline planes can not land with full tanks for example, they have to dump or burn off fuel before landing.

Lars-J, I believe that 50 t you refer to has to do with the performance ( delta v ) of the BFS from Mars as it does not refuel in LMO.

TrueBlueWitt · « **Reply #30 on:** 10/09/2017 08:57 pm »

Timing of First Block 5 launch?

Doesitfloat · « **Reply #31 on:** 10/09/2017 09:09 pm »

When does the "backlog" of flight become just flight reservations?

Lar · « **Reply #32 on:** 10/09/2017 09:21 pm »

Quote from: TaurusLittrow on 10/08/2017 07:30 pm

Upvoted. Pity it's not possible to vote the Chicago way (early and often).

It is of course cheating to vote more than once. And using different browsers, your friends computers, different VMs, etc are all apparently[1] not detected in this voting system so you are on your honor not to do that.

1 - someone told me that. I would never try it myself.

Ronsmytheiii · « **Reply #33 on:** 10/09/2017 09:34 pm »

Forgot to post my name:

Quote

What new commercial earth-centric markets do you see emerging as a result of cheap launch prices? Will SpaceX try satellite servicing/repair/return with BFR?

Robotbeat · « **Reply #34 on:** 10/09/2017 10:13 pm »

Quote from: Ronsmytheiii on 10/09/2017 09:34 pm

Forgot to post my name:

Quote
What new commercial earth-centric markets do you see emerging as a result of cheap launch prices? Will SpaceX try satellite servicing/repair/return with BFR?

Didnt Musk already say "yes" during the presentation?

Ronsmytheiii · « **Reply #35 on:** 10/10/2017 05:15 am »

Quote from: Robotbeat on 10/09/2017 10:13 pm

Quote from: Ronsmytheiii on 10/09/2017 09:34 pm
Forgot to post my name:

Quote
What new commercial earth-centric markets do you see emerging as a result of cheap launch prices? Will SpaceX try satellite servicing/repair/return with BFR?
Didnt Musk already say "yes" during the presentation?

No, he mentioned clearing space debris and ISS servicing, but nothing on satellite servicing or repair.

Semmel · « **Reply #36 on:** 10/10/2017 06:23 am »

Some economic question: What satellite markets are you hoping to service with BFR that requires it's capabilities and launch cadence?

RocketmanUS · « **Reply #37 on:** 10/11/2017 12:33 am »

Quote from: Lars-J on 10/09/2017 06:47 am

Quote from: RocketmanUS on 10/09/2017 06:23 am
1 ) Can the BFS land back on Earth with a 150 t payload? That is can the structure handle this much payload on landing on Earth?

2 ) What is the mass limit of the NFS landing on Earth ( dry mass + unused propellant + payload )?

Elon already said that the max landing payload is 50 t. (view 2017 IAC talk again) Please don't ask questions that we already know the answer to, it just limits the amount of new stuff we might learn.

Rewatched the presentation, linked from SpaceX website. What Elon said was 20 to 50 t returnable from Mars by the BFS with no booster ( or no LMO refueling , implied ), this is at 35:21.

What I asked was what the BFS is capable of landing back on Earth. I did not ask from were the BFS was coming from as it did not matter. What does matter is what the BFS structure can handle on landing. Space shuttle was designed to launch up to 65.000 lb, later revised to launching maximum 50,000 lb. However space shuttle could only land with 35,000 lb of cargo, just like commercial jets can not land with full tanks , the structure can not handle it. Important to know if there is a sub orbital abort or an orbital abort.

OneSpeed · « **Reply #38 on:** 10/11/2017 01:34 am »

Quote from: RocketmanUS on 10/11/2017 12:33 am

Rewatched the presentation, linked from SpaceX website. What Elon said was 20 to 50 t returnable from Mars by the BFS with no booster ( or no LMO refueling , implied ), this is at 35:21.

What I asked was what the BFS is capable of landing back on Earth. I did not ask from were the BFS was coming from as it did not matter. What does matter is what the BFS structure can handle on landing. Space shuttle was designed to launch up to 65.000 lb, later revised to launching maximum 50,000 lb. However space shuttle could only land with 35,000 lb of cargo, just like commercial jets can not land with full tanks , the structure can not handle it. Important to know if there is a sub orbital abort or an orbital abort.

The limitation is not structural. For redundacy, the ship needs to be able to land on a single Raptor SL, which has about 170mT of thrust. If the ship is 85mT, and landing propellant is another 35mT, then 50mT is the maximum payload.

Robotbeat · « **Reply #39 on:** 10/11/2017 01:47 am »

Quote from: OneSpeed on 10/11/2017 01:34 am

Quote from: RocketmanUS on 10/11/2017 12:33 am
Rewatched the presentation, linked from SpaceX website. What Elon said was 20 to 50 t returnable from Mars by the BFS with no booster ( or no LMO refueling , implied ), this is at 35:21.

What I asked was what the BFS is capable of landing back on Earth. I did not ask from were the BFS was coming from as it did not matter. What does matter is what the BFS structure can handle on landing. Space shuttle was designed to launch up to 65.000 lb, later revised to launching maximum 50,000 lb. However space shuttle could only land with 35,000 lb of cargo, just like commercial jets can not land with full tanks , the structure can not handle it. Important to know if there is a sub orbital abort or an orbital abort.

The limitation is not structural. For redundacy, the ship needs to be able to land on a single Raptor SL, which has about 170mT of thrust. If the ship is 85mT, and landing propellant is another 35mT, then 50mT is the maximum payload.

Of course, for large cargo payloads you can just land on 2.