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SpaceX is Developing a Reusable VTVL Rocket

Wanderlust

Wanderlust

Captain
Captain
SpaceX is developing an 106-foot tall reusable vertical takeoff and vertical landing (VTVL) rocket called Grasshopper based upon the first stage of the Falcon 9 rocket. It has applied for an experimental permit to conduct a series of flights up to 11,500 feet at its engine testing facility in McGregor, Texas.

One of SpaceX’s key goals is to be able to reuse the first stage of the Falcon 9, an aim that is considered crucial for its long-range business plan. Being able to fly a first stage back and land it intact would help the company accomplish its goal. On the initial two Falcon 9 launches, the first stages fell into the sea and were not in good enough shape to reuse.

http://www.parabolicarc.com/2011/09/24/spacex-is-developing-a-reusable-vtvl-rocket/

http://www.faa.gov/about/office_org...0110922 SpaceX Grasshopper Draft EA.Final.pdf
 
Interesting. You should have quotes on your text since it came straight from the article you linked.
 
This is an example of where I don't think the Spaceship Company (Scaled Composites and Virgin) are thinking far enough ahead. A remotely piloted or automatic lifting body design would be a great innovation for lifting a rocket propelled stage above the bulk of the atmosphere - much like Pegasus launchings, or the old rockoon idea. I don't see any need for a human pilot to be physically present in the vehicle.
 
New video from SpaceX showing the eventual use of Grasshopper research:

[yt]http://www.youtube.com/watch?v=p176UpWQOs4&feature=player_embedded[/yt]

Cool video.
 
Interesting - I wonder what the payload overheads are for the extra fuel, landing struts, avonics, and 2nd stage heat shield, and whether it all pays off economically. The extra complexity probably means that you wouldn't always be able to recover the 1st and 2nd stages in a reusable condition. I also doubt that one would feel secure enough to do away with a backup parachute system for the Dragon capsule.
 
Asbo Zaprudder said:
Interesting - I wonder what the payload overheads are for the extra fuel, landing struts, avonics, and 2nd stage heat shield, and whether it all pays off economically. The extra complexity probably means that you wouldn't always be able to recover the 1st and 2nd stages in a reusable condition. I also doubt that one would feel secure enough to do away with a backup parachute system for the Dragon capsule.
Click to expand...

That was my thought as well.
 
A backup parachute is a given.

If they are left with enough payload margin after adding in all the extra's to make the stages re-usable, economic viability is obvious. I have read comments on other forums that indicate a loss of 1/3 of the current max payload estimate weight - which is definitely still in the useful range.
 
They're going to need a separate landing site for the 2nd stage, aren't they? Surely the vehicle would be too far downrange to reverse direction and land back at the launch site without using a hideous amount of fuel, and it wouldn't have sufficient velocity to complete nearly a complete orbit.
 
Asbo Zaprudder said:
They're going to need a separate landing site for the 2nd stage, aren't they? Surely the vehicle would be too far downrange to reverse direction and land back at the launch site without using a hideous amount of fuel, and it wouldn't have sufficient velocity to complete nearly a complete orbit.
Click to expand...
If the second stage engines are being used to insert the spacecraft into an orbit with an apogee outside most of the atmosphere (with spacecraft thrusters used to raise the perigee) the stage would reenter after nearly a full orbit. However, the Earth's rotation would shift the launch site quite a distance east (perhaps over a thousand miles - varies with launch site's latitude). As far north as any sites in the continual US (like Florida, California, Arizona, New Mexico or Texas) are that would leave the launch site well out of the second stage's orbital plane.
 
Asbo Zaprudder said:
They're going to need a separate landing site for the 2nd stage, aren't they? Surely the vehicle would be too far downrange to reverse direction and land back at the launch site without using a hideous amount of fuel, and it wouldn't have sufficient velocity to complete nearly a complete orbit.
Click to expand...


Yeah, think about it. The second stage inserts the payload into orbit, hence it must attain orbit. It has to do a re-entry burn to come back down as seen in the video.
 
Asbo Zaprudder said:
Interesting - I wonder what the payload overheads are for the extra fuel, landing struts, avonics, and 2nd stage heat shield, and whether it all pays off economically. The extra complexity probably means that you wouldn't always be able to recover the 1st and 2nd stages in a reusable condition. I also doubt that one would feel secure enough to do away with a backup parachute system for the Dragon capsule.
Click to expand...
They've been talking about powered landings for Dragon since at least February, no parachutes required. The reusable Falcon concept is new, though, and I think it might actually be a reaction to Blue Origin's New Shepherd spacecraft; Elon probably read something about it on a blog somewhere and then asked his engineers "Why can't we do something like that?" to which they replied, "Maybe we can?"

The tricky part is going to be the reusable upper stage and getting it to survive reentry in a recoverable condition. The propellant issue isn'[t that much of a problem; it's a lot easier to slow something down from terminal velocity than it is to accelerate to orbital velocity; energy wise, it's like the difference between driving up a steep hill and racing across the state at 150mph.

I'm not concerned about the added complexity; if there's one thing SpaceX does well, it's improving on their existing technology. I'm more interested in whether or not they can justify the added weight of the additional systems without sacrificing payload performance.
 
sojourner said:
Asbo Zaprudder said:
They're going to need a separate landing site for the 2nd stage, aren't they? Surely the vehicle would be too far downrange to reverse direction and land back at the launch site without using a hideous amount of fuel, and it wouldn't have sufficient velocity to complete nearly a complete orbit.
Click to expand...


Yeah, think about it. The second stage inserts the payload into orbit, hence it must attain orbit. It has to do a re-entry burn to come back down as seen in the video.
Click to expand...

Ah, okay. If it attains orbit, it might also be economically viable to consider re-purposing the spent stage as a inhabitable module.
 
^more cost effective to re-use it as is for further launches. For all the gear you would need to add to do the "refurbishment" once it's in orbit, you might as well launch a purpose built hab module.
 
I assume Bigelow Aerospace are still in the picture with regard to inflatable modules. You don't hear much about them nowadays.
 
Joke aside, it is possible to record a video like that (the entire sequence) by launching two rockets in parallel and landing their stages in parallel, and it will be more than amazing if we ever pull off a feat like to have footage of an actual flight recorded.
 
It's probably doable with duplicated mission control facilities and separate telemetry and control channels, but aside from the coolness factor, what would be the point?
 
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