SpaceX Grasshopper Takes Off and Lands Vertically [video]
crazyengineers.com
crazyengineers.com
http://www.youtube.com/watch?v=wv9n9Casp1o
This is important, as in practice only turbopump rockets have enough performance for orbital uses. If it can routinely and safely land vertically, then it's very easy to build a reusable first stage out of this.
If everything works out, a reusable Falcon could fly every few days: Ideally you'd just refuel and go again, like an airplane.
In this first generation though I expect a lot of maintenance and handwork by lots of people every flight.
This will require a whole ecosystem too: low maintenance satellites that can be slapped on the rocket and launched at any time. Otherwise very flexible operations too like low overhead range and radar tracking sevices, safety zones etc.
If the rocket can abort and land in case of problems, and demonstrates good safety by flying a lot, then a lot of safety criteria can be relaxed, which should enable better flexibility.
Since they have the landing and low speed part pretty much covered, they're now looking at the high speed and altitude problematics.
The Stig lands with a steerable chute.
High speed stability, drag and turning for powered landing are a nasty problem field where testing is hard and expensive. Interplay of aerodynamics in a wide speed range, center of gravity shifts and everything else.
Burt Rutan's SpaceshipOne solved it elegantly with feathering: the descent was safe and easy. The mechanism could be troublesome though.
I wouldn't put too much stock in SpaceshipOne's descent scheme. It's not clear at all that's going to work from orbit.
And for a first stage, returning is not nearly as hard.
At first, the reusable first stage might provide only a modest portion of the delta vee and an expendable second stage would do most of the work. That would mean a low payload.
I don't think the SpaceshipOne solution would work "as is", but something like it might work. It only went vertically to 100 km.
When the Space Shuttle was being designed, Max Faget toyed around with different ideas on how to arrange re-entry, with essentially something similar as SpaceshipOne in a sense: a high drag configuration at high speed and then flying at low speed. http://www.astronautix.com/lvs/shuenara.htm
The space shuttle was a disaster from a cost perspective. I don't know how many lessons we can draw from the program beyond "don't do it this way".
We can draw a lot of lessons from the space shuttle - it was very successful in lifting re-entries. It takes a huge amount of expensive wind tunnel and test time to develop something like this.
Why STS was so expensive must be analyzed more deeply - we definitely can not afford to waste all the lessons learned in that program. I think, in details, it contained many technologies that were not robust and required lots of checking and hand work (people with salaries). This also made it less reliable. Strategically, it was a huge one off program, meaning there was no possibility of iteration and trial and error: feeding information from operations back to improving design. (Cue Gall's law.)
Since development is so expensive (afaik a lot of the testing infrastructure has been driven down), this is also why most space capsules use known-to-work shapes: Vostok, Mercury, Gemini, Apollo or Soyuz. Some small capsule designs have even used Corona spysat film return canister shape.
1) Take off from the pad.
2) Loss of vehicle control (chute deploys), Loss of engine
3) Engine restart.
4) Attitude recovery after engine restart
5) Return to pad capability.
I had no ideas these guys were that far along.
... with what, like 0.0001% of SpaceX's budget and other resources...?
Maybe SpaceX should hire Armadillo...
I had no idea he was involved with a project like this, and for so long. Too bad they don't appear to have been very active recently.
- Masten Space Systems: https://www.youtube.com/user/mastenspace
- Unreasonable Rocket: https://www.youtube.com/watch?v=_PO5cTb_T5M (Couldn't find a better video now)
http://www.blueorigin.com/updates/updates-2011-11-17-video-o...
Do you have any advice for my next application to Blue Origin? My strongest points are my unending passion for spaceflight, science and desire to better myself. My code and software engineering skills improve by the hour (...it's Christmas in two hours and I'm working on pressureNET and reading HN). I have some excellent projects under my belt but I have no experience working on spaceships or related systems.
But I'm not sure what else I can do. So if you have some advice that would be fantastic.
Edit: And yes, I'm a US citizen.
I know that I need to improve. I am still hoping that there are other angles, other things I can do, so that the answer to my question is NOT "25 year olds are bad. Come back when you're 40 and already have three of your own spaceships in orbit".
I'm not sure about SpaceX specifically, but if you were a Green Card holder. e.g O-1 Exceptional Ability, then you'd be considered a US Person for ITAR compliance.
From http://www.spacex.com/careers.php "To conform to U.S. Government space technology export regulations, applicant must be a U.S. citizen, lawful permanent resident of the U.S., protected individual as defined by 8 U.S.C. 1324b(a)(3), or eligible to obtain the required authorizations from the U.S. Department of State."
It doesn't sound like SpaceX require a Secret/Top Secret clearance for most of their employees. Some other space companies (Orbital Science Corp, ULA/Boeing/Lockheed Martin) do because they work on missile systems like ICBMs in related programs.
From what I understood, most engineers who make the grade to work at SpaceX, would be O-1 visa eligible as well. The O-1 is not tied to continued employment at a particular company.
http://en.m.wikipedia.org/wiki/International_Traffic_in_Arms...
Either way, very interesting
Since fuel is the cheap part anyway, Space X is betting that they can make it economically sound to launch a bit more fuel than they would normally need to if it means they can get the (expensive) rocket stage back.
Ist the much more importend things the time and cost of getting the rocket back to where you want it much bigger?
You'd still need to steer the rocket there but you can avoid worrying about vertical landing.
That's the end goal. And since not all bodies SpaceX may want to land on have a comparable atmosphere to Earth, parachutes are not part of the plan.
This isn't the vehicle that's going to do all that, but they have to start somewhere to build the tech that eventually will.
SpaceX Grasshopper avoids either destroying the first stage, or a labor intensive and expensive recovery process.
No, but I'm sure I read that right and the machine existed.
> I thought the SRB segments are quite structurally strong and the parachutes quite large and effective.
They are, but the stresses are large, the diameter is large, and the requirements quite stringent. If a casing is out of round by a small fraction, this might still cause the o-rings to not be pressed against the casings tightly enough.