Register here

Author Topic: Space X Interplanetary Transport System  (Read 10139 times)

Offline Michel Van

  • Senior Member
  • CLEARANCE: Top Secret
  • **
  • Posts: 3560
Re: Space X Interplanetary Transport System
« Reply #15 on: September 28, 2016, 12:14:23 am »


Honestly, I doubt those folks much care, except maybe NASA.  They know that the ITS, successful or not, is not relevant for commercial space launch services.  Demand for launches in the existing weight classes isn't going to dry up just because SpaceX can lob 400 tons at Mars every so often.  Heck, this probably helps ULA and Ariane because SpaceX engineering talent that could be refining a next gen Falcon Heavy successor will instead be designing the non-commercial ITS.

Yes
Therefor is very interesting that Musk mention in presentation incidental
About to use the Booster as suborbital Intercontinental cargo flights (ROMBUS)
If SpaceX manage to create this market, they can finance there Mars project
I love Strange Technology

Offline ADVANCEDBOY

  • CLEARANCE: Secret
  • **
  • Posts: 263
Re: Space X Interplanetary Transport System
« Reply #16 on: September 28, 2016, 01:44:52 am »
At first you need to show a capability to build a LOX for Venture Star/X-33 size vehicle before going  any further. If you can`t build a colony on The  Moon , you can`t do it on Mars either. There is no existing expertise to land a man on the Moon let alone on Mars no matter how much I would like to be wrong.
If you are hotter than me, I must be cooler than you:)


Offline Orionblamblam

  • Secret Projects Guru
  • Top Contributor
  • CLEARANCE: Top Secret
  • ***
  • Posts: 6737
    • Aerospace Projects Review
Re: Space X Interplanetary Transport System
« Reply #18 on: September 28, 2016, 03:00:35 am »

About to use the Booster as suborbital Intercontinental cargo flights (ROMBUS)


Not the booster, but the spacecraft itself. I believe *that* was what he said could be made into an SSTO or a suborbital hopper. The SSTO option seems of dubious value, since the ship would be stuck on orbit unable to come back unless refueled, but the suborbital hopper seems like it might be of some value. but I believe he was wrong on his estimates of flight times. I believe trans-Atlantic is more than 10 minutes...
Aerospace Projects Review


And so the endless circle of life comes to an end, meaningless and grim. Why did they live, and why did they die? No reason. Two hundred million years of evolution snuffed out, for in the end Nature is horrific and teaches us nothing

Offline fredymac

  • CLEARANCE: Top Secret
  • ***
  • Posts: 802
Re: Space X Interplanetary Transport System
« Reply #19 on: September 28, 2016, 04:03:03 am »
Raptor engine test at McGregor site.  I think this is a subscale demonstrator and that the full size version is to be tested at Nasa Stennis.


Offline flanker

  • CLEARANCE: Top Secret
  • ***
  • Posts: 797
Re: Space X Interplanetary Transport System
« Reply #20 on: September 28, 2016, 04:40:06 am »
The idea of landing the booster back on the launch pad and recycling it within 24 hours (implied) seems pretty incredible.  As in, I don't think that's a credible approach.  They're nowhere close to that level of precision in their landings yet.

Okei, so in vacuum your points would be correct and fair. But you are ignoring two major things;

1; History.

2; As Elon often says, one doesn't know one is on an exponential curve until one zooms out.

Do you know what their accuracy was with the first landings like CASSIOPE and CRS-3? About 10km +/-. About a year later they got that down to like 10-20 meters. Year later still, they landed a stage, for first time ever. By anyone. Less than a year after that again, they had landed half dozen, many of which were within 1-2m of bulls eye. If they managed to go from landing 0 stages within 1-2m to landing safely 6 stages in just little over 2 years - why is it logical to assume they won't improve on that even more in 6 years or so? So you are at best operating as if we were in 2013.

As to the second point, before any BFR-ITS ever flies, they would have A LOT of F9/FH flights under their belts. They managed to land safely 6 stages in under a year. Before BFR-ITS ever flies it will be over a hundred stages. A hundred landings and 6 years to improve accuracy even more and to test out technology and software they dont have *today*. Don't underestimate just how rapidly they are developing technology.

Pulled high res pictures from the presentation, all here; http://imgur.com/a/NRIvz
« Last Edit: September 28, 2016, 04:42:01 am by flanker »
Push the envelope,watch it bend.

Offline observer144

  • CLEARANCE: Restricted
  • Posts: 3
  • I really should change my personal text
Re: Space X Interplanetary Transport System
« Reply #21 on: September 28, 2016, 06:02:44 am »
The idea of landing the booster back on the launch pad and recycling it within 24 hours (implied) seems pretty incredible.  As in, I don't think that's a credible approach.  They're nowhere close to that level of precision in their landings yet.

Okei, so in vacuum your points would be correct and fair. But you are ignoring two major things;

1; History.

2; As Elon often says, one doesn't know one is on an exponential curve until one zooms out.


Personally, I don't doubt that SpaceX can obtain the accuracy. The issue is about risk mitigation. Assumption: Lift-off and landing, like an aircraft, are the most risky parts of the flight. If there were an issue with the landing (and no complex system can be made 100% without fault), the risk is that it could damage the launch/landing pad. This would take the launch pad out of commission while the repairs are made and investigation into what went wrong.

From a risk mitigation perspective, it would be far better to land the stage back 'near' the launch pad. That way you could continue to fly if one of the landings fails. This is especially critical if SpaceX continues to plan to launch passengers first, then their fuel. The launch pad would seem to be a single-point-of-failure; a new launch pad could take a year or more to build but a new landing pad should be easy to build in a few months - it's not like America has a problem making parking lots :).

And talking about the passenger plans, it would seem lower risk to launch all the fuel first (as others on this thread have stated), and have the tankers LEO rendezvous, then launch the passengers and again LEO rendezvous with the tankers, refuel, and finally TMI (trans-Mars injection).


-r.
« Last Edit: September 28, 2016, 06:09:38 am by observer144 »

Offline TomS

  • Senior Member
  • CLEARANCE: Top Secret
  • **
  • Posts: 2154
Re: Space X Interplanetary Transport System
« Reply #22 on: September 28, 2016, 08:23:07 am »
This is my main issue -- an accident on a fixed pad during landing kills the entire launch infrastructure for weeks (minimum) and has a high chance of at least dinging the spacecraft waiting to be loaded.  (Same issue on launch, too.  A pad accident like the most recent one would also destroy the other waiting vehicle, if it's as close as shown). It makes sense, IMO, to get the landing pad away from the launch site.

Assuming they can achieve the required precision, perhaps the solution is to use a set of mobile pads similar to the Crawler-Transporters at KSC now but designed to work as part of the launch/land system.  Launch from one such pad, then land on another one a half-mile or so away (or whatever your safe distance looks like).  Then swap the crawlers, bringing the one with the recovered booster back to the launch site while the one that just launched the booster moves over to the recovery site for the next landing.  A similar  vehicle can bring the next spacecraft payload to the launch site from a safe distance as well. 

Admittedly, this is more launch infrastructure, and thus more cost, but I'd bet it's cheaper than replacing the pad facilities or one of the spacecraft after an accident.


Offline sferrin

  • Senior Member
  • CLEARANCE: Top Secret
  • **
  • Posts: 8969
Re: Space X Interplanetary Transport System
« Reply #23 on: September 28, 2016, 08:37:28 am »
Assuming they can achieve the required precision, perhaps the solution is to use a set of mobile pads similar to the Crawler-Transporters at KSC now but designed to work as part of the launch/land system.  Launch from one such pad, then land on another one a half-mile or so away (or whatever your safe distance looks like).  Then swap the crawlers, bringing the one with the recovered booster back to the launch site while the one that just launched the booster moves over to the recovery site for the next landing.  A similar  vehicle can bring the next spacecraft payload to the launch site from a safe distance as well.

I was thinking something just like this.  :)  It also gives you options for taking it to a VAB relatively easy if something needs to be looked at or replaced.
"DARPA Hard"  It ain't what it use to be.

Offline red admiral

  • CLEARANCE: Secret
  • **
  • Posts: 454
Re: Space X Interplanetary Transport System
« Reply #24 on: September 28, 2016, 11:16:44 am »
Related landing question:

How large a hole are those engines going to plow when it lands vertically on Mars?

I can see a definite need for pre-missions to scout and establish a landing site, and probably pre-position anciliary equipment and fuel production facilities.

Offline blackstar

  • Senior Member
  • CLEARANCE: Top Secret
  • **
  • Posts: 1602
Re: Space X Interplanetary Transport System
« Reply #25 on: September 28, 2016, 01:12:23 pm »
Don't underestimate just how rapidly they are developing technology.

And don't over-hype it either: Falcon Heavy was supposed to fly in 2012.

Offline blackstar

  • Senior Member
  • CLEARANCE: Top Secret
  • **
  • Posts: 1602
« Last Edit: September 28, 2016, 02:36:10 pm by blackstar »

Offline sferrin

  • Senior Member
  • CLEARANCE: Top Secret
  • **
  • Posts: 8969
Re: Space X Interplanetary Transport System
« Reply #27 on: September 28, 2016, 02:48:46 pm »
"I like to imagine SpaceX planted these questioners to make the guy on stage talking about colonizing Mars look like the sane one in the room."


That is just sad.  That somebody could think that pretty much summarizes today's twitterati generation.
"DARPA Hard"  It ain't what it use to be.

Offline flanker

  • CLEARANCE: Top Secret
  • ***
  • Posts: 797
Re: Space X Interplanetary Transport System
« Reply #28 on: September 28, 2016, 05:20:12 pm »
Don't underestimate just how rapidly they are developing technology.

And don't over-hype it either: Falcon Heavy was supposed to fly in 2012.

Sure, if one ignores the reason for the delays time after time. FH in 2012 is not the same FH in 2016. Between then and now they have been through 3 major versions of Falcon 9 with one more coming up next year. So if anything - you just proved my point. ;)

And i am not over hyping it. It is a fact that they have been through 3 major versions of Falcon 9 in 3 years or so. Dragon 2 in 2012 doesnt look anything like Dragon 2 from 2016 either.
« Last Edit: September 28, 2016, 05:22:18 pm by flanker »
Push the envelope,watch it bend.

Offline blackstar

  • Senior Member
  • CLEARANCE: Top Secret
  • **
  • Posts: 1602
Re: Space X Interplanetary Transport System
« Reply #29 on: September 28, 2016, 06:44:45 pm »
Sure, if one ignores the reason for the delays time after time. FH in 2012 is not the same FH in 2016. Between then and now they have been through 3 major versions of Falcon 9 with one more coming up next year. So if anything - you just proved my point. ;)

Now you're being silly.

Missing deadlines is not a good thing, no matter what the excuse.