SpaceX: General Falcon and Dragon discussion (Thread 5)

[Comga]

Can you really say with authority that the outer 8 engines aren't canted to pass closer to vehicle CG for controlability reasons, Saturn I-style?

No I cannot, and have absolutely NO authority or inside knowledge.  It's just that images of the cluster shows no indication of canting, particularly the 11 degrees necessary to cause a 2% cosine loss.

But this is silly.  A cosine loss is a much less likely explanation than just bad numbers in the FlightGlobal article.

[Lars_J]

Aviation Week with a smackdown on SpaceX and their slips.

http://www.aviationweek.com/aw/generic/story.jsp?id=news/awst/2012/03/12/AW_03_12_2012_p49-431419.xml&headline=SpaceX%20Loses%20Gleam%20Slips%20With%20Launch%20Plans&channel=space

I bet everyone else in aerospace is happy that SpaceX is the only one affected by slips.

[ugordan]

It's just that images of the cluster shows no indication of canting

The image I posted isn't convincing enough for you?

But this is silly. A cosine loss is a much less likely explanation than just bad numbers in the FlightGlobal article.

Who's even talking about the FG article? I was talking about the slight disparity between 1st stage thrust of 854 klbf and more often reported thrust of a single M1c of around 96 klbf.

Going back to the press kit, I can now see the single engine thrust is given as 95 klbf so there's practically no difference to the 854/9 klbf average thrust.

[neilh]

Aviation Week with a smackdown on SpaceX and their slips.

http://www.aviationweek.com/aw/generic/story.jsp?id=news/awst/2012/03/12/AW_03_12_2012_p49-431419.xml&headline=SpaceX%20Loses%20Gleam%20Slips%20With%20Launch%20Plans&channel=space

Which part was the smack-down? Are you talking about the John Logsdon quotes?

[dunderwood]

The image I posted isn't convincing enough for you?

The angle of the engines when firing may be different than the angle when they're not firing.  Depends on how heavy and stiff that thrust structure is.

[docmordrid]

>
I want to see the picture with how much space is left with a real ECLSS integrated...

AIUI  the "floor" of both crew and cargo Dragon sits over the lowermost portion of the pressure vessel, which contains the ventilation system. To my eye this looks big enough to house the Paragon modular EC/LSS developed in CCDev-1. Paragon is a SpaceX CCDev partner.

Cargo Dragon ventilation PDF illustrates the space under the floor....

Paragon milestone completion PDF....

Dragon pressure vessel (sub-floor in lowermost section)

Image link....

[neilh]

Musk is right. It was really sad to see people tear apart commercial crew in Congress, and I have a hard time understanding why they would do that. I don't understand the venom (sometimes concealed or denied, but still undeniable) directed toward commercial crew--an American effort if there ever was one--by other Americans.

Regarding what Musk said in the 60 Minutes clip, does anyone know if Cernan or Armstrong have actually done site visits to SpaceX, ULA, or any of the other commercial crew competitors? I'd assume they'd be interested in doing some research on the American companies they've been criticizing.

[dcporter]

Is SpaceX developing the Merlin 2?
Are they developing the Raptor?

Unclear at this time.

[mr. mark]

The real smack down will come when Dragon berths with ISS. When and if that happens it will be on all the news networks. Of course it could go the other way but if successful the American people will be in Spacex's corner. Everyone loves a winner.

[beancounter]

The real smack down will come when Dragon berths with ISS. When and if that happens it will be on all the news networks. Of course it could go the other way but if successful the American people will be in Spacex's corner. Everyone loves a winner.

Incorrect premise.  Repeated polls have demonstrated that most 'American people' have no interest whatsoever in space and that applies to most of Congress as well.  There may be 5 seconds of fame on a couple of news channels and then, that'll be about it except for pollie posturing in a few hearings - unfortunately.

[docmordrid]

Update

http://www.spacex.com/updates.php

[ChefPat]

Update

http://www.spacex.com/updates.php

Looks pretty roomy.
I'd like to see how they'd configure it for a Crew plus Cargo run.

[dcporter]

Looks pretty roomy.
I'd like to see how they'd configure it for a Crew plus Cargo run.

How much extra work would it be to yank out the back three couches and put cargo racks back there? Like, just that much, or do you have to simulate the weight distro somewhere and rewrite all the software?

[ChefPat]

Looks pretty roomy.
I'd like to see how they'd configure it for a Crew plus Cargo run.

How much extra work would it be to yank out the back three couches and put cargo racks back there? Like, just that much, or do you have to simulate the weight distro somewhere and rewrite all the software?

Weight distribution would play the primary role IMO.

[Jason1701]

Looks pretty roomy.
I'd like to see how they'd configure it for a Crew plus Cargo run.

How much extra work would it be to yank out the back three couches and put cargo racks back there? Like, just that much, or do you have to simulate the weight distro somewhere and rewrite all the software?

I think that for the BEO version of Dragon those back three couches could be replaced with storage, galley, and head facilities.

[cuddihy]

I suspect those would go in an attached "Hab module" that Dragon would be docked to, not in Dragon.

[Ben the Space Brit]

This is completely unformed speculation about a version of Dragon that we are only guessing is even in SpaceX's plans.  Nonetheless:

I agree that the back seats will be removed in that version of Dragon.  However, I suspect that it will only be replaced by storage and a little leg-room.  With the possible exception of a minimalist waste handling system, I would expect all major long-duration hab equipment would be in the mission module, be it hab, lander or whatever.

[Space Pete]

First info on Trunk payloads for SpX-2 and SpX-3!

http://forum.nasaspaceflight.com/index.php?topic=27980.msg874026#msg874026

[Comga]

First info on Trunk payloads for SpX-2 and SpX-3!

http://forum.nasaspaceflight.com/index.php?topic=27980.msg874026#msg874026

 Also visible in the HRSGF image are four PPODs oriented at ~90 degrees,  suggesting that they are planning for eight around the upper rim of the second stage.  That's 24 U!  SpaceX will solidify their position as the dominant launcher of nanosats.

I am pushing to get a nanosat development funded for this opportunity.  (For a later flight than CRS-3, of course)  Anyone else?

edit: typo correction and clarification

[tigerade]

First info on Trunk payloads for SpX-2 and SpX-3!

http://forum.nasaspaceflight.com/index.php?topic=27980.msg874026#msg874026

Very interesting.  Do we have any info on the possible payloads for SpX-1?