Author Topic: SpaceX: General Falcon and Dragon discussion (Thread 6)  (Read 237966 times)

Offline Chris Bergin

Thread 6 for general discussion on SpaceX and their vehicles.

Previous threads (now over 1.3 milllion views for the five SpaceX threads alone):

Thread 1:
http://forum.nasaspaceflight.com/index.php?topic=19228.0

Thread 2:
http://forum.nasaspaceflight.com/index.php?topic=22769.0

Thread 3:
http://forum.nasaspaceflight.com/index.php?topic=24179.0

Thread 4:
http://forum.nasaspaceflight.com/index.php?topic=25597.0

Thread 5:
http://forum.nasaspaceflight.com/index.php?topic=28006.0


SpaceX news articles on this site:
Old: http://forum.nasaspaceflight.com/index.php?topic=21862.0 (links)

Then recent news articles, not linked above, as we moved to a tag group system:
All recent: http://www.nasaspaceflight.com/tag/spacex/


L2 SpaceX - now a large section:
http://forum.nasaspaceflight.com/index.php?action=tags&tags=SpaceX


NOTE:
These are very busy threads. Remember, this site is 99+ percent read by people not logged in to post. When you post, lots and lots of people get to read it. So, make it a worthwhile post, be civil and remember this is a community.

Offline mrmandias

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Re: SpaceX: General Falcon and Dragon discussion (Thread 6)
« Reply #1 on: 07/19/2012 03:45 pm »
Thanks, Chris B.

---

Does anyone have any word at all on SpX-1 and the reviews on COTS 2/3?  It seems like its been nothing but silence.

Offline rst

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Re: SpaceX: General Falcon and Dragon discussion (Thread 6)
« Reply #2 on: 07/19/2012 07:02 pm »
Does anyone have any word at all on SpX-1 and the reviews on COTS 2/3?  It seems like its been nothing but silence.

There's an update thread in the "SpaceX Missions" section.  The current GSFC Mission Set database has it listed with an Oct. 5 launch date.

Not sure there's been anything public on the reviews, but given how the mission went, everyone seems to think that's mostly pro forma at this point...

Offline go4mars

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Re: SpaceX: General Falcon and Dragon discussion (Thread 6)
« Reply #3 on: 07/20/2012 07:32 pm »
Elon Musk will be delivering the keynote address at the Mars Society convention August 4th in Pasadena.  If any of you can make it, a summary of comments posted here (or video if those are allowed) would be much appreciated.  I hope it's the much awaited unveiling of the SpaceX Mars architecture. 
Elasmotherium; hurlyburly Doggerlandic Jentilak steeds insouciantly gallop in viridescent taiga, eluding deluginal Burckle's abyssal excavation.

Online docmordrid

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Re: SpaceX: General Falcon and Dragon discussion (Thread 6)
« Reply #4 on: 07/20/2012 07:46 pm »
That would be worth another 2-3 million hits for Chris & Co. ;)
DM

Offline kirghizstan

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Re: SpaceX: General Falcon and Dragon discussion (Thread 6)
« Reply #5 on: 07/20/2012 07:52 pm »
That would be worth another 2-3 million hits for Chris & Co. ;)

i might have to sign up for l2 just to help pay for the increased traffic
« Last Edit: 07/20/2012 07:52 pm by kirghizstan »

Offline Idiomatic

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Re: SpaceX: General Falcon and Dragon discussion (Thread 6)
« Reply #6 on: 07/20/2012 07:58 pm »
I hope it's the much awaited unveiling of the SpaceX Mars architecture. 

In a wired/google+ interview (just before the last launch) he said the mars plan would be shown in several months around 4 if i remember correctly. So this seems unlikely.

Offline neilh

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Re: SpaceX: General Falcon and Dragon discussion (Thread 6)
« Reply #7 on: 07/20/2012 08:13 pm »
Elon Musk will be delivering the keynote address at the Mars Society convention August 4th in Pasadena.  If any of you can make it, a summary of comments posted here (or video if those are allowed) would be much appreciated.  I hope it's the much awaited unveiling of the SpaceX Mars architecture. 

Overall weekend tickets are pretty steep ($200+), although apparently banquet-only tickets are $50. Hmm...

Wasn't Zubrin also reportedly working on restructuring Mars Direct to use Falcoh Heavies?
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Offline schaban

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Re: SpaceX: General Falcon and Dragon discussion (Thread 6)
« Reply #8 on: 07/20/2012 08:19 pm »
timing is rather curious... Curiosity EDL just several hours after...

Offline go4mars

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Re: SpaceX: General Falcon and Dragon discussion (Thread 6)
« Reply #9 on: 07/20/2012 08:26 pm »
I just re-read the e-mail.  It is a SpaceX-centric vision of what I was hoping for.  My wife's sister is getting married on the 5th, and I'll have my house stuffed with out of town family, yet I keep wondering what she'd say to a red eye flight back in time for the wedding...             I'll have to catch it after the fact but if there are any science and space reporters out there, this is a big big event IMO.  Peter Diamandis, Buzz Aldrin, Bob Zubrin, and some other big names will be there too.
« Last Edit: 07/21/2012 01:26 am by go4mars »
Elasmotherium; hurlyburly Doggerlandic Jentilak steeds insouciantly gallop in viridescent taiga, eluding deluginal Burckle's abyssal excavation.

Offline cro-magnon gramps

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Re: SpaceX: General Falcon and Dragon discussion (Thread 6)
« Reply #10 on: 07/20/2012 08:49 pm »
I just re-read the e-mail.  It is a SpaceX-centric vision of what I was hoping for.  My wife's sister is getting married on the 5th, and I'll have my house stuffed with out of town family, yet I keep wondering what she'd say to a red eye flight back in time for the wedding...             I'll have to catch it after the fact but if there are any science and space reporters out there, this is a big big event IMO.  Diamandis and some other big names will be there too.

how does, "Your so dead, if you step one toe outside that door!!" sound to you!!! just 22 years of experience talking ;D ;D
 
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Online docmordrid

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Re: SpaceX: General Falcon and Dragon discussion (Thread 6)
« Reply #11 on: 07/20/2012 10:22 pm »
I just re-read the e-mail.  It is a SpaceX-centric vision of what I was hoping for.  My wife's sister is getting married on the 5th, and I'll have my house stuffed with out of town family, yet I keep wondering what she'd say to a red eye flight back in time for the wedding...             I'll have to catch it after the fact but if there are any science and space reporters out there, this is a big big event IMO.  Diamandis and some other big names will be there too.

how does, "Your so dead, if you step one toe outside that door!!" sound to you!!! just 22 years of experience talking ;D ;D
 
Gramps

Yup. 30+ years speaking here: keep your buttkus in place or she's going to hurt you, not to mention being shut out of the adult playroom for weeks/months.
« Last Edit: 07/20/2012 10:23 pm by docmordrid »
DM

Offline go4mars

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Re: SpaceX: General Falcon and Dragon discussion (Thread 6)
« Reply #12 on: 07/21/2012 01:31 am »
Lol.  12 years and counting.  Strong as my passion may be for space nerdfests, my passion for her is stronger still. 

If only there was a hypersonic transit system up and running already...

Have fun without me!  And bring your tripod and boom-mike!  ;)
Elasmotherium; hurlyburly Doggerlandic Jentilak steeds insouciantly gallop in viridescent taiga, eluding deluginal Burckle's abyssal excavation.

Offline Jason1701

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Re: SpaceX: General Falcon and Dragon discussion (Thread 6)
« Reply #13 on: 07/21/2012 02:30 am »
Elon Musk will be delivering the keynote address at the Mars Society convention August 4th in Pasadena.  If any of you can make it, a summary of comments posted here (or video if those are allowed) would be much appreciated.  I hope it's the much awaited unveiling of the SpaceX Mars architecture. 

Count on me.

Offline douglas100

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Re: SpaceX: General Falcon and Dragon discussion (Thread 6)
« Reply #14 on: 07/21/2012 09:40 am »
timing is rather curious... Curiosity EDL just several hours after...

Slightly tempting fate, isn't it? A day or two later might have been better...
Douglas Clark

Offline Maciej Olesinski

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Re: SpaceX: General Falcon and Dragon discussion (Thread 6)
« Reply #15 on: 07/21/2012 11:39 am »
I just re-read the e-mail.  It is a SpaceX-centric vision of what I was hoping for.  My wife's sister is getting married on the 5th, and I'll have my house stuffed with out of town family, yet I keep wondering what she'd say to a red eye flight back in time for the wedding...             I'll have to catch it after the fact but if there are any science and space reporters out there, this is a big big event IMO.  Peter Diamandis, Buzz Aldrin, Bob Zubrin, and some other big names will be there too.
Oh well 4th im going on wedding too - but I am going to be one of two main actors there ;) And 5th we always do some sort of afterparty - and I am afraid I will be not tracking MSL landing live (will use phone tho). But thanks to MSL I will not foget my wedding date.
I would apriciate that someone could record whole Mars Society convention.

p.s. Sorry for offtopic
« Last Edit: 07/21/2012 11:40 am by placydo »

Offline mgfitter

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Re: SpaceX: General Falcon and Dragon discussion (Thread 6)
« Reply #16 on: 07/24/2012 03:00 am »
I've spent the last few hours trying to work out the specifications for the Falcon 9 and something just isn't adding up here, so I thought I would ask people like Ed what it might be that I'm not seeing correctly.

Starting with the Merlin 1C, it has a published vac Isp of 304.8sec and a vac Thrust of 138,000lbf. That suggests that its normal fuel consumption rate would be 447.4708lb/sec in steady-state operation.

Using the timeline from the last Falcon 9 flight (C2+), the stage used all 9 engines for 172 seconds and then used 7 engines for a further 11 seconds.

Ignoring whatever is used during the shutdown procedure, I'm getting a total of 727,140lb of used propellant.

That's (447.4708*9*172)+(447.4708*7*11)

But the information available online (NSF, Wiki, SpaceLaunchReport, Astronautix etc) suggests that the first stage only contains a maximum of 527,561lb -- which is also more consistent with the official GLOW for the entire vehicle.

Clearly the rocket burned its engines for that full duration, so either there has to be a lot more propellant than we think (or that the official GLOW figure suggests), or the Merlin-1C wasn't burning as much propellant, so couldn't have been producing the full thrust performance.

This discrepancy is puzzling me. I'm sure its probably just me getting something mixed-up, but I need someone to help shed some light on where my mistake is, because I can't see it.

-MG.

Offline Go4TLI

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Re: SpaceX: General Falcon and Dragon discussion (Thread 6)
« Reply #17 on: 07/24/2012 03:25 am »
It would seem you are not accounting for throttling

Offline dwightlooi

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Re: SpaceX: General Falcon and Dragon discussion (Thread 6)
« Reply #18 on: 07/24/2012 04:20 am »
But the information available online (NSF, Wiki, SpaceLaunchReport, Astronautix etc) suggests that the first stage only contains a maximum of 527,561lb -- which is also more consistent with the official GLOW for the entire vehicle.

527,561lbs = 239.5 tons

That's way less than the Falcon 9 1st stage ought to weight. The Falcon 9 is a 330 ton vehicle meaning that the 1st stage should be closer to 300 tons than 240 tons. SpaceX didn't publish their figures, but a 1st stage of around 300 tons and an upper stage of about 30 tons sounds about right for a 2 stage RP-1/LOX vehicle. This brings the propellant load closer to your estimates.

Offline Prober

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Re: SpaceX: General Falcon and Dragon discussion (Thread 6)
« Reply #19 on: 07/24/2012 04:31 am »
I've spent the last few hours trying to work out the specifications for the Falcon 9 and something just isn't adding up here, so I thought I would ask people like Ed what it might be that I'm not seeing correctly.

Starting with the Merlin 1C, it has a published vac Isp of 304.8sec and a vac Thrust of 138,000lbf. That suggests that its normal fuel consumption rate would be 447.4708lb/sec in steady-state operation.



believe your using thrust levels for the 1C that has never been used.
 
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