Author Topic: SpaceX: General Falcon and Dragon discussion  (Read 880649 times)

Offline SpacexULA

  • Full Member
  • ****
  • Posts: 1756
  • Liked: 46
  • Likes Given: 73
Re: SpaceX: General Falcon and Dragon discussion
« Reply #260 on: 12/23/2009 05:48 PM »
I don't find that a convincing conjecture.  It was definitely labeled Dragonlab in the text below the figure, but they mix illustrations for Dragon and Dragonlab.  One would think it easier to just replace the grapple fixture for a dedicated mission, which could provide more capacity without an added mechanism.
 
Any other ideas?

Of course.  It's part of their nefarious plan to steal the boom rendezvous concept from me.  ;-)

~Jon

Did Gaetano hack Jon's account?
No Bucks no Buck Rogers, but at least Flexible path gets you Twiki.

Offline FinalFrontier

  • Senior Member
  • *****
  • Posts: 3834
  • Space Watcher
  • Liked: 255
  • Likes Given: 131
Re: SpaceX: General Falcon and Dragon discussion
« Reply #261 on: 12/23/2009 06:01 PM »
I don't find that a convincing conjecture.  It was definitely labeled Dragonlab in the text below the figure, but they mix illustrations for Dragon and Dragonlab.  One would think it easier to just replace the grapple fixture for a dedicated mission, which could provide more capacity without an added mechanism.
 
Any other ideas?

Of course.  It's part of their nefarious plan to steal the boom rendezvous concept from me.  ;-)

~Jon

Did Gaetano hack Jon's account?
Thats a distinct possibility ;)
3-30-2017: The start of a great future
"Live Long and Prosper"

Offline Chandonn

  • Extreme Veteran
  • Full Member
  • ****
  • Posts: 1227
  • "Pudding!!! UNLIMITED Rice Pudding!!!"
  • Lexington, Ky
  • Liked: 5
  • Likes Given: 9
Re: SpaceX: General Falcon and Dragon discussion
« Reply #262 on: 12/23/2009 07:41 PM »
February 2 is Groundhog's Day in the U.S.  Therefore, according to tradition, if the groundhog sees his shadow, there will be 6 more weeks until the launch of Falcon 9.  ;)

Offline jongoff

  • Recovering Rocket Plumber/Space Entrepreneur
  • Senior Member
  • *****
  • Posts: 6048
  • Lafayette/Broomfield, CO
  • Liked: 2038
  • Likes Given: 692
Re: SpaceX: General Falcon and Dragon discussion
« Reply #263 on: 12/23/2009 08:29 PM »
I don't find that a convincing conjecture.  It was definitely labeled Dragonlab in the text below the figure, but they mix illustrations for Dragon and Dragonlab.  One would think it easier to just replace the grapple fixture for a dedicated mission, which could provide more capacity without an added mechanism.
 
Any other ideas?

Of course.  It's part of their nefarious plan to steal the boom rendezvous concept from me.  ;-)

~Jon

Did Gaetano hack Jon's account?

Heh.  You recognized the allusion.  :-)

Of course, picking on Gaetano is sort of like shooting a very slow fish in a very small barrel.

~Jon
« Last Edit: 12/23/2009 08:30 PM by jongoff »

Offline simonbp

Re: SpaceX: General Falcon and Dragon discussion
« Reply #264 on: 12/24/2009 12:37 AM »
Obviously, it's a prototype warp nacelle; the other one is just obscured behind the Dragon. You didn't think Musk was crazy enough to try to go to Mars with chemical rockets, did you? :)
« Last Edit: 12/24/2009 12:37 AM by simonbp »

Offline WHAP

  • Member
  • Full Member
  • ****
  • Posts: 795
  • Liked: 104
  • Likes Given: 8
Re: SpaceX: General Falcon and Dragon discussion
« Reply #265 on: 12/24/2009 04:10 AM »
Some info here, not sure if its new...:
Space x says the curent target date for Falcon 9 maden flight is Febuary 2nd. Any thought on whether they will make this date or not?

As Atlas/SDO has the Range for February 3, February 2 is not currently available to SpaceX.  The Range typically schedules each vehicle for two days, with 24 hours to reconfigure for the next vehicle (assuming there is another vehicle waiting).  Since the shuttle has the 7th (assuming that date is confirmed on the Range), the next opportunity for SpaceX is the 10th.  If either Atlas or Shuttle launches in its first opportunity or has to slip to a later date, then a window may open up for SpaceX to launch sooner.

I realize that's not quite the question you asked.  The SpaceX Update thread has had a little more speculation on the launch date.  I personally don't see that they will be ready to launch on 2/2.  They had some problems during earlier testing of their ground system, and it doesn't appear that all of the parts of their flight vehicle are at the launch site yet, which means that they haven't performed a full tanking test of their vehicle at the launch pad.  That's typically done more than once for a new vehicle and pad combination.  Those tests typically provide opportunities for discovery and learning, and SpaceX's history is similar to that of all other launch providers (i.e., they'll probably find something that needs to be fixed).  I say they won't be ready earlier than mid-March.  Other people may not agree, and they'll provide their reasons.  Of course, this is all just idle speculation, but sometimes that's fun.
ULA employee.  My opinions do not necessarily reflect those of my employer.

Offline docmordrid

  • Senior Member
  • *****
  • Posts: 4314
  • Michigan
  • Liked: 1452
  • Likes Given: 1
Re: SpaceX: General Falcon and Dragon discussion
« Reply #266 on: 12/24/2009 07:11 AM »
In the DragonLab PDF that same detail, absent the extensible boom and instrument, is shown in the title image.  In the drawings that opening is labeled as a "Sensor Bay Volume", the lid a "Sensor Bay Hatch", and it too is located just below the side hatch.

Quote
Sensor Bay (unpressurized, recoverable)

Approx 0.1 m3 (4cuft) volume
Hatch opens after orbit insertion; closes prior to reentry
Electrical pass-throughs into pressure vessel

I see no reason why this wouldn't be a common feature between Dragon and Dragonlab - why make two versions, especially if you're going to re-use them and don't know ahead if a sensor would be needed or not over a capsules several missions? 

I've attached two images;

The first is a crop of the DragonLab title image with labels consistent with what's in the rest of the document.

The second is the image from a few posts ago but magnified, rotated to match the same position, sharpened to better show edges and also cropped.

IMO the only difference is that the sensor is deployed in the latter and not in for former.
« Last Edit: 12/24/2009 07:22 AM by docmordrid »
DM

Offline Jim

  • Night Gator
  • Senior Member
  • *****
  • Posts: 31343
  • Cape Canaveral Spaceport
  • Liked: 9624
  • Likes Given: 299
Re: SpaceX: General Falcon and Dragon discussion
« Reply #267 on: 12/24/2009 12:25 PM »
  They had some problems during earlier testing of their ground system, a

Like an LO2 pump explosion

Offline Comga

  • Senior Member
  • *****
  • Posts: 3924
  • Liked: 1236
  • Likes Given: 1055
Re: SpaceX: General Falcon and Dragon discussion
« Reply #268 on: 12/24/2009 03:55 PM »
In the DragonLab PDF that same detail, absent the extensible boom and instrument, is shown in the title image.  In the drawings that opening is labeled as a "Sensor Bay Volume", the lid a "Sensor Bay Hatch", and it too is located just below the side hatch.

IMO the only difference is that the sensor is deployed in the latter and not in for former.

The first image shows the logical alternative, replacing the unneeded grapple fixture with an exposure fixture.  The question remains as to what could be on that extendible boom.

Frankly that hatch has enough requirements already.  It has to withstand aero loads on launch, open on orbit, be rigid for grappling, close prior to reentry, and remain water-tight on landing.  Adding a boom would seem to add a critical, mission threatening failure mode.  What deployable device would make that worthwhile?
What kind of wastrels would dump a perfectly good booster in the ocean after just one use?

Offline Patchouli

  • Senior Member
  • *****
  • Posts: 4238
  • Liked: 128
  • Likes Given: 220
Re: SpaceX: General Falcon and Dragon discussion
« Reply #269 on: 12/24/2009 04:21 PM »
newbie question..and slightly a side question
 there is J2 heritage so, here is my ignorance showing through... why such a long development if they are making a J-2x? is there that much a difference or what makes a H2O2 engine so hard to make/design?   or is making a "raptor" engine from scratch a better move?
jb
The main shared component between the J-2 and J-2X is the name.  I also am led to believe that the turbopump is similar in design as well.

I think Raptor probably would be more closely related to LCPE then anything else.
But probably would use a simple turbo cycle like Merlin.
http://www.space.com/businesstechnology/technology/trw_rocketengine_000926.html

Offline Nascent Ascent

  • Full Member
  • ****
  • Posts: 606
  • Liked: 21
  • Likes Given: 40
Re: SpaceX: General Falcon and Dragon discussion
« Reply #270 on: 12/24/2009 04:25 PM »
IF (and I know this is a big if) SpaceX wanted to build a lunar lander - would they have to develop new engines? Or could they use (or adapt) one or two from their existing portfolio?
“Why should we send people into space when we have kids in the U.S. that can’t read”. - Barack Obama

Offline docmordrid

  • Senior Member
  • *****
  • Posts: 4314
  • Michigan
  • Liked: 1452
  • Likes Given: 1
Re: SpaceX: General Falcon and Dragon discussion
« Reply #271 on: 12/24/2009 07:34 PM »
What deployable device would make that worthwhile?
Seems to me it would make it easier to point a directional sensor (imager, particle catcher etc.) if it were extended on a boom.  Otherwise you'd have to point it by re-orienting the capsule, which might affect other portions of the mission.  It would also make it easier for a sensor to look in the direction of travel if the capsule were moving TPS first, which would otherwise produce a significant blind spot from that position.
DM

Offline mlorrey

  • Member
  • Senior Member
  • *****
  • Posts: 2133
  • International Spaceflight Museum
  • Grantham, NH
  • Liked: 10
  • Likes Given: 0
Re: SpaceX: General Falcon and Dragon discussion
« Reply #272 on: 12/25/2009 10:09 AM »
IF (and I know this is a big if) SpaceX wanted to build a lunar lander - would they have to develop new engines? Or could they use (or adapt) one or two from their existing portfolio?

They would likely scale the Kestrel pintle injection engine up to 30k-40k lbs thrust with an ability to throttle down to 10k lbs or less. This would put it on a par with the Apollo LM Descent engine.
VP of International Spaceflight Museum - http://ismuseum.org
Founder, Lorrey Aerospace, B&T Holdings, ACE Exchange, and Hypersonic Systems. Currently I am a venture recruiter for Family Office Venture Capital.

Offline sdsds

  • Senior Member
  • *****
  • Posts: 5478
  • "With peace and hope for all mankind."
  • Seattle
  • Liked: 577
  • Likes Given: 677
Re: SpaceX: General Falcon and Dragon discussion
« Reply #273 on: 12/25/2009 09:59 PM »
IF (and I know this is a big if) SpaceX wanted to build a lunar lander - would they have to develop new engines? Or could they use (or adapt) one or two from their existing portfolio?

They would likely scale the Kestrel pintle injection engine up to 30k-40k lbs thrust with an ability to throttle down to 10k lbs or less. This would put it on a par with the Apollo LM Descent engine.

Has there ever been a rocket engine operating in the vicinity of the Moon that used other than hypergolic propellants?
-- sdsds --

Offline eeergo

  • Phystronaut
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 4759
  • Milan, Italy; Spain; Virginia
  • Liked: 434
  • Likes Given: 352
Re: SpaceX: General Falcon and Dragon discussion
« Reply #274 on: 12/25/2009 10:19 PM »

Has there ever been a rocket engine operating in the vicinity of the Moon that used other than hypergolic propellants?

Yes: SMART-1's ion engine, for example.
-DaviD-

Offline sdsds

  • Senior Member
  • *****
  • Posts: 5478
  • "With peace and hope for all mankind."
  • Seattle
  • Liked: 577
  • Likes Given: 677
Re: SpaceX: General Falcon and Dragon discussion
« Reply #275 on: 12/25/2009 11:21 PM »

Has there ever been a rocket engine operating in the vicinity of the Moon that used other than hypergolic propellants?

Yes: SMART-1's ion engine, for example.

Good point!  That's another type of engine that can turn on in deep space.  Is there a SpaceX propulsion design that could be adapted to do that?

The original question was:
IF (and I know this is a big if) SpaceX wanted to build a lunar lander - would they have to develop new engines? Or could they use (or adapt) one or two from their existing portfolio?
-- sdsds --

Offline mlorrey

  • Member
  • Senior Member
  • *****
  • Posts: 2133
  • International Spaceflight Museum
  • Grantham, NH
  • Liked: 10
  • Likes Given: 0
Re: SpaceX: General Falcon and Dragon discussion
« Reply #276 on: 12/26/2009 11:37 PM »

Has there ever been a rocket engine operating in the vicinity of the Moon that used other than hypergolic propellants?

Yes: SMART-1's ion engine, for example.

When I was in the air force, and we handled LOX, there was very strict rules about venting LOX when greases or waxes or fuels were around. THe claim was that wearing combat boots that had been polished  was a no-no because a drop of LOX falling on a polished boot would explode like a grenade, never mind contacting any fuel spills on the uniform or boots. If any of this information was even partially accurate, it seemed to me that LOX should be hypergolic with kerosene. If it isn't why isn't it?
VP of International Spaceflight Museum - http://ismuseum.org
Founder, Lorrey Aerospace, B&T Holdings, ACE Exchange, and Hypersonic Systems. Currently I am a venture recruiter for Family Office Venture Capital.

Offline kkattula

  • Member
  • Senior Member
  • *****
  • Posts: 2508
  • Melbourne, Australia
  • Liked: 10
  • Likes Given: 3
Re: SpaceX: General Falcon and Dragon discussion
« Reply #277 on: 12/27/2009 12:55 AM »

Has there ever been a rocket engine operating in the vicinity of the Moon that used other than hypergolic propellants?

Yes: SMART-1's ion engine, for example.

When I was in the air force, and we handled LOX, there was very strict rules about venting LOX when greases or waxes or fuels were around. THe claim was that wearing combat boots that had been polished  was a no-no because a drop of LOX falling on a polished boot would explode like a grenade, never mind contacting any fuel spills on the uniform or boots. If any of this information was even partially accurate, it seemed to me that LOX should be hypergolic with kerosene. If it isn't why isn't it?

IIRC, if LOX soaks into a fuel like boot polish or coal or asphalt, it can form a shock sensitive explosive. So the boot wouldn't explode immediately, it would probably wait until you stamped to attention.

Coal & LOX used to a common mining explosive, but there were too many unexpected detonations.

Offline Ben the Space Brit

  • Senior Member
  • *****
  • Posts: 6995
  • A spaceflight fan
  • London, UK
  • Liked: 553
  • Likes Given: 637
Re: SpaceX: General Falcon and Dragon discussion
« Reply #278 on: 12/27/2009 10:13 AM »

Has there ever been a rocket engine operating in the vicinity of the Moon that used other than hypergolic propellants?

Yes: SMART-1's ion engine, for example.

Good point!  That's another type of engine that can turn on in deep space.  Is there a SpaceX propulsion design that could be adapted to do that?

You could fit three or four in the bottom of a DragonLab's trunk.  Add bigger solar arrays for SEP propulsion power supply and, voila! You have a DragonLab-based Mars or Venus probe.  WITH an Earth return capsule.  Mars Sample Return MOR anyone?
"Oops! I left the silly thing in reverse!" - Duck Dodgers

~*~*~*~

The Space Shuttle Program - 1981-2011

The time for words has passed; The time has come to put up or shut up!
DON'T PROPAGANDISE, FLY!!!

Offline Jim

  • Night Gator
  • Senior Member
  • *****
  • Posts: 31343
  • Cape Canaveral Spaceport
  • Liked: 9624
  • Likes Given: 299
Re: SpaceX: General Falcon and Dragon discussion
« Reply #279 on: 12/27/2009 01:03 PM »

When I was in the air force, and we handled LOX, there was very strict rules about venting LOX when greases or waxes or fuels were around. THe claim was that wearing combat boots that had been polished  was a no-no because a drop of LOX falling on a polished boot would explode like a grenade, never mind contacting any fuel spills on the uniform or boots. If any of this information was even partially accurate, it seemed to me that LOX should be hypergolic with kerosene. If it isn't why isn't it?

none of those items were hypergolic, they would form a gel that was shock sensitive, which means it needed an energy source to detonate.

Tags: