A Bigger Leap for Grasshoppper
Video: Grasshopper 250m Test Flight
“SpaceX’s Grasshopper flies 820 feet, tripling its March 7th leap. Grasshopper is a 10-story Vertical Takeoff Vertical Landing (VTVL) vehicle that SpaceX has designed to test the technologies needed to return a rocket back to Earth intact. While most rockets are designed to burn up in the atmosphere during reentry, SpaceX’s rockets are being designed to return to the launch pad for a vertical landing.”
Cowboy mannequin or it didn’t happen.
Johnny the mannequin is there. You can see him near the beginning of the video. From the waist up. He’s on the right.
40m -> 80m – 250m in three hops, and this time sigh significant wind. Before long they’ll run out of GH1 capabilities and GH2 will come to bat.
Doc:
Elon Musk said that they wanted to go supersonic with Grasshopper this year, but he didn’t say which Grasshopper would accomplish this.
Folks:
Rumors of Grasshopper 2 flying out of White Sands have been circulating for some some time now. For high altitude flights the fuel load would require them to launch Grasshopper off a launch table (basically, a mini launch pad) with the landing legs retracted. It may even require three engines depending on how much of the flight envelope they intend to fly.
Don’t worry, Grasshopper 1 can go higher and faster, we just don’t know quite how much yet. Somehow I don’t think we’ll be hearing sonic booms over central Texas though.
tinker
Folks:
Great flight for SpaceX with impressive aerial shots of the Texas countryside. You can see Grasshopper lean into the breeze.
A point about first stages being designed “to burn up in the atmosphere during reentry” . They do not burn up and are in fact hardened against exterior heat. What happens to most first stages is structural failure when they hit the atmosphere at high speed at some oblique angle. It’s not heat but fast changing air pressure like a punch in the guts that damages them. There is further break up from buffeting and some thermal damage until the whole mess slams into the water and that does the real damage.
The Russians don’t even bother with the water part. All the Russian launch vehicles that fly from Baikonore have designated ‘landing zones’ for their first stages, none of which is in water. The Soyuz first stage strap-on boosters were designed in such a way that they would ‘land’ in these zones (one for each orbital path). Even the new launch site in the far east has land based drop zones for the four first stage Soyuz boosters. The site is not on the eastern coast of Russia like you may think. Old habits die hard, I guess.
Being told they ‘burn up’ makes it seem all neat and clean when it’s not. That always bugged me.
Good to get that one off my shoulder, especially when a solution for this travesty of a ‘communication error’ is in site!
tinker
Tinker,
There is a whole cottage industry on the Russian steppes of local nomads and villagers scavenging the crashed rocket parts for scrap metal and wiring. Some sell the scraps back to the Russian space agency, some sell the scrap to metal recyclers and dealers and a few even use the metal to fashion make-shift shelters (think lean-tos made out of the side of a fuel tank.) Very ingenious, these Ruskies!
SH:
LOL! Yes, I know about this! Kazak surface mining. All the power to them. You’d think the Russians would make their lives a little easier by using late deploying parachutes so they could haul the scrap off the steppes in one piece (more or less).
tinker
The landing part of the video looked just a 50’s SF movie rocket landing, which is where a lot of us, I think, got our original interest. When the video finished I suddenly realized that I had this big silly grin on my face. This, ladies and gentlemen, is something that we’ve been waiting on for a long time. Thank you SpaceX.
Steve:
I’m still grinning! Oh, and that hexcopter drone footage was to get engineering data, right? Nope, they did that for our benefit, I’m sure!
tinker
Footage was both for engineering and PR purposes.
Naw! No good! No V-2 type fins on it! The test site does have some resemblance to “Space Academy USA, in the world beyond tomorrow, 2350 AD!” from the intro to “Tom Corbett, Space Cadet”! Seriously, GO, SpaceX!
I appreciate the enthusiasm but I have a math question (I am not an engineer). If it takes X amount of fuel to get the stage into orbit and put a payload into space, and then it takes X-c to bring it back, how big will this thing have to be? Is this really a viable option?
It’s big — 106 feet tall. But by comparison, the first stage of the Saturn V stack was 138 feet tall and the standard Shuttle ET was 153.8 feet tall.
As for viability, that would have been one of the very first questions that the SpaceX engineers asked themselves, if not the very first. If the math hadn’t shown it to be viable they wouldn’t have announced it, let alone designed and built it. The same logic applies for the newer version 1.1. I think you can safely take it as a given that it will work, it’s just a question of optimizing it and measuring actual performance numbers. The math that validates the VTVL approach goes back at least as far as the German engineers of the early 1940’s, and as technology has improved so has the viability of the concept. The big question is, Will it work well enough?
What makes it more viable now is not so much the size and the fuel required, as the improvements in the various control systems. Programmable systems make design changes and testing a lot faster and cheaper than ever before, and also add the ability to tweak performance parameters on the fly. Manufacturing methods and materials science have both improved in quality while their prices have come way down (but labor overheads, of course, keep going up).
Yes, it will work. It’s just a matter of how well and how expensive. SpaceX, and presumably others, are now thinking more in terms of reuse (like an aircraft turn-around) instead of refurbishment (like the Shuttle stack components), which will make it far more viable from a cost standpoint.
I just hope they take their time with this, since any setbacks are ammunition for people who build expendable LVs and don’t really want to see VTVL recoverable, reusable stages work, at least not until they can do it themselves as well, and do it competitively.
Also, AFAIK, they’re considering only first stage recovery. The extra fuel, landing gear, etc, don’t have to get all the way to orbit.
Second-stage recovery has also been referenced in SpaceX documents and presentations. In some ways, if you assume a once around and down approach, it’s a little simpler than first-stage recovery (at least West to East). Thermal shielding required, however.
Yes, second-stage recovery is easier in some ways, but harder in other ways.
The first stage costs far more than the second stage, though, so it makes sense to make the first stage reusable first. If you have a re-usable second stage but expendable first stage, launch costs come down maybe 10%-20% at best. If you have a re-usable first stage, launch costs might come down 80%-90%.
Oh, Heinlein, thou should be living at this hour! Lovely!
Irritating question: does SpaceX have permission to fly a partly-fuelled rocket back to a launch pad over potentially populated areas? Would not “ambulance-chasers r us” not circle a potential failure like vultures? Is this under the FAA?
Magnificent tech. Problem in a world of “health and safety gone mad”? I hope not.
cuibono:
I think it’ll be a while before you see a orbital launch site in America that isn’t beside water. Even if the first stage is recoverable, having the stack hit water if there is an engine failure or range issue makes a lot of sense! Case in point:
http://www.youtube.com/watc…
So, no first stages returning over populated areas or even land for that matter. For second stage recovery, on the other hand, there might be some exceptions allowed. the second stage of Falcon would be only twice the size of Dragon and about the same mass. To return to launch site it would come from the west so going over land would be a necessity. Like the Shuttle reentry profiles, they can avoid heavily populated areas on the way down. It’s a big difference to have something the size of a delivery van auger in than something Grasshopper sized.
Oh? I think I can hear Robert Anson Heinlein’s voice in the wind right now…
“Now there’s a rocket landing as God meant it to be!”
tinker
Thanks tinker! Just me worrying unneccessarily.
You can have the best engineering in the world, but if the lawyers get involved, you’re still doomed!
It would be more of an issue for Orbital and their solid second stage. That one, I hope, won’t be allowed to try landing anywhere but water, in any mode or scenario!
Yeah, a solid second stage isn’t going to be landing anywhere except in the water by parachute, at best. You can’t throttle-down and re-light a solid!
cuibono:
Yes, Grasshopper flight fall under FAA regulations (which are a work in progress where SpaceX is a prime test case).
tinker
Yeah, Grasshopper flights aren’t really much different from test flights of new aircraft of various sorts, and those are allowed by the FAA on a regular basis, just as Grasshopper’s flights are.
Chris, Tinker,
This is certainly not the first VTVL test flight in the US (government or commercial), so I would have thought that the precedents would be pretty well ironed out by now. I suspect that an actual mission, or a test flight that goes either out of country or to space altitude, might come under a different set of rules and perhaps a different agency.I wonder what would happen if the UN tried to create and delegate authority to an international body (Space Traffic Control?). Given that the economic issues of space activities are more of a reality every day, I think it would be smart for UN members to vote Yes to such a proposal, especially those with infant or no space operations at this time, because it would be 1,000 times harder to change the rules later.We need to legally ensure and enforce the idea of space being “for all mankind.” The Outer Space Treaty and the Moon Treaty are referred to only when they are convenient arguments; I don’t think any countries are taking them seriously.Steve
If this proves to be a problem, then a lot of self-proclaimed inland “spaceports” are in trouble.
Steve,
You have a good point but I think too much has been invested in the FAA regulations for the U.S. to go along with a UN treaty governing launches. We failed to ratify the Moon Treaty when it opened for signature in 1979 – 7 years after deciding that we weren’t going back to the Moon. Aside from the Registration Convention, all other international treaties were ratified by the U.S. during the Apollo era. I would argue that the U.S. is pro treaty as a barrier to entry for others, but against treaties when it is not the leader of activities governed by the treaty.
Daniel, Chris,
I, too, am in favor of the “if it’s not broke don’t fix it” approach, but there are issues that are not addressed by the current state of affairs. And it will get more sticky, and dangerous, as more countries get into space.
One thing that has been an issue right from the start is the fact that a country’s government is legally and financially liable for damages or any other costs incurred by other parties. Right now we are pushing hard for private space operations, as opposed to government operations. In the past only governments could afford space activities. Now that has changed, but the liabilities are still with the governments. That has to change too, and rules have to be set up, or else we’ll end up with governments disallowing non-government launches unless the private company pays a huge “deposit” of some sort to cover potential costs. As things stand, a single incident could wipe out all of the commercial space progress over night.
I feel strongly that it’s better to develop solutions before the problems hit, so that they can be sensible solutions instead of being tied to a particular incident.
To date, we’ve been adhering to a non-treaty loose agreement, but no one is forced to abide by any part of the the existing treaties since they been ignored by consensus. We can’t continue to live with a free-for-all, and any solution has to be international and legally binding. What alternative is there to the UN?
Steve
Back at the start of the Space Age, various countries claimed launch vehicles and even vehicles in orbit couldn’t legally overfly their territory. Fortunately, the countries that had the ability to launch to orbit simply ignored them, and now we have decades of precedent that no country can prohibit satellites in orbit above its territory or vehicles on launch or return trajectories over their territory. The common-sense limit is airspace that ordinary fixed-wing aircraft can reach is the limit of a country’s territorial airspace. Obviously, if a launch fails or a satellite falls out of orbit and does damage in some country, the country that launched the vehicle is responsible for making good the damages, and there’s an international agreement to that effect.
I don’t see anything to be gained by having the U.N. claim control of space launches or orbital operations, and a whole lot to be lost. I think the current system works fine. After all, the current system is pretty much the way international waters work — anyone can pass through international waters, and the country a ship is registered in is responsible if that ship does damage to another country.
Are you kidding? This is Texas, where everything is bigger, and where we let fertilizer companies store 300 tons of ammonium nitrate within a stone’s throw of elementary schools and nursing homes. We scoff at the threat posed by your puny rocket stage! But if it flies too low, we might shoot at it…
Ya know, Billy Bob said much the same thing, right before the shrapnel got him.
Not much farther to the takeover altitude for the 1st flight. Looks like they will be ready in June. If they can’t send a video Webcast, I wish they had a play by play with a satellite phone.
Once they’re done with all their other Grasshopper 1 flights, I’d like to see them take off, go up to altitude, shut off the engine, let it free fall a bit, then re-light the engine and land. It’s risky, but they need to be able to do that to recover a first stage.
Chris:
Don’t expect engine out/relight happening with this vehicle. I’m pretty sure this is a terminal landing demonstrator and not much else. They won’t get proper flight data with all that gear, legs and such, hanging out like that. Stability at high speed, up & down, would suffer as well.
Grasshopper 2 will test flight hardware more closely matching the reusable stage and that will give them actual flight profile data they can directly use. Also, at White Sands they have a much broader landing area and ‘craters’ would be far easier to ‘deal with’ ;).
tinker
Antares what now? :_>
Tried not to grin when it landed. Lol couldn’t help it. Just had to 🙂
DTARS:
Just imagine …seven reusable Falcon stages sweeping down to a row of landing pads after tossing 175 tons into an orbital trajectory… 😀
tinker
Can you say, Wernher von Braun?
Tinker
It seems obvious to me that affordable heavy lift will be bunch of recoverable cores around one large tank like your lifter.
I don’t have to just imagine it. It seems like I know it. It’s just to practical not to happen.
PARALLEL LINES
DTARS:
On a side note, SpaceX’s first stage landing method is similar to the stage recovery for my MegaLifter™ launch vehicle design. The difference is that I had chosen helicopter recovery instead of rocket powered landing. The stages would have helicopter blades that deploy after jettison based on the Rotary Rocket design and, using tip thrusters, fly back to the landing zone. Four of the six boosters would return to launch site after launch, two with a short trip back and the other two with a 500 mile flight back which would take four hours. The final two boosters would carry the 500 ton payload to orbit, spacecraft in their own right. After delivering the cargo, the boosters would de-orbit and deploy the blades at terminal velocity to fly back to launch site.Using tip thrusters on the blades with hypergolic propellant, the weight cost was small enough for hours of flight, based on Roton’s research, even though it added hardware (blades, tanks, structure) that would only be used on the way down, dead weight on the way up.I like Elon’s idea better. It’s simpler and, in a way, doesn’t require any new technology, just a very reliable rocket engine and smart software. I’m incorporating that into my design :).
tinker
Tinker,
Good design change. Keeping all situations open, you’d want something that could “land” on an aircraft carrier or large barge, or maybe even soft land on water. I suspect that the turbulence from a rotary system with tip thrusters wouldn’t allow you enough lateral stability, especially with a cross wind. I think main engines (vertical) with lateral thrusters under computer control is the only safe way to go, until someone invents something better than a rocket.
Steve
Steve:
The Rotary Rocket test vehicle was pretty successful. In one piloted flights, they traveled down a runway a few thousand feet. Another test flight flew straight up out of ground effect.
Unfortunately, that’s as far as they got. One notable point is that the rocket engine they chose to use passed some of it’s heritage on to the Merlin engine.
tinker
Grasshopper is being tested under an FAA Experimental Permit.
Experimental permits are
issued “to launch or reenter a reusable suborbital rocket only for research and
development to test new design concepts, new equipment, or new operating
techniques; a showing of compliance with requirements for obtaining a license;
or crew training before obtaining a license for a launch or reentry using the
design of the rocket for which the permit would be issued.” Experimental permits authorize an
unlimited amount of launches for a suborbital rocket design for a period of one
year with the opportunity of renewal.
I don’t think anyone can argue anymore that SpaceX and Orbital aren’t at least the equals of NASA in building reliable, state-of-the-art launchers and landers.
With $396 and $288 million respectively for development and technology transfers from NASA through the COTS program I would expect them to be as reliable. Not to mention the money SpaceX is getting through Commercial Crew.
Not enough data for both launchers and landers. Neither SpaceX nor Orbital have attempted anything close to the complexity of the MSL lander, and NASA’s only attempted it once. So there’s nothing to compare for reliability.
And for launchers, NASA hasn’t developed one since the 70s, so they have no state of the art launchers to compare to anything for reliability.
MSL was built and operated by JPL, which is a contractor.
I’m with the ‘huge grin’ brigade on this one. I can’t wait to see these tests each one has been more exciting than the last.
Elon and SPaceX are planning to ‘land’ the next F9 to orbit on its tail over water the very next shot they take at the ISS.
I wonder if we’ll get to see it or now, will look amazing.
They’re farther along the road than it might appear. Oh so exciting.
I would imagine OldSpace are looking on with some dismay.
JJ:
We’re not quite sure when SpaceX will start water landing tests or when the first flight of the Falcon v1.1 is going to be. The Falcon upgrade is a big step for SpaceX. It is more powerful and therefore longer to carry the extra fuel it will need. They have also built a new transport/erector that uses a different method to attach the rocket to the pad. In terms of integration procedures, you might as well call the Falcon v1.1 a new rocket. Expect delays but not overtly long ones. How well this process goes will say a lot about whether SpaceX can turn innovation into success.
tinker
Does anyone know much of this relied on the experience of the Delta Clipper?
Jack:
Delta Clipper was meant to be a Single Stage To Orbit (SSTO) vehicle. It would have landed on a runway like the Shuttle. It’s engines were unique in that they were ‘AeroSpike’ motors, Google it for details.
That said, there’s not much in common between reusable Falcon stages and Delta Clipper. But, even though the Delta Clipper was cancelled, it was a NASA program and they don’t throw away things lightly. Maybe a few things NASA learned will get passed on to SpaceX for use somewhere in their development. Hope that helps answer your question.
tinker
What about the flight/controll software? It seem to me that there is a lot of commonality despite the hardware differences.
Jack:
If there was software transfer it would be of a very generic nature. Delta Clipper (X-31) was a horizontal landing unpowered glider like the Space Shuttle.
A big project like Delta Clipper would have loads of ‘granular’ data, small contained lessons, procedures and, yes, hardware that can be passed on if possible. A lot of the best ideas have nothing more to show other than data showing good or bad results through testing. Even the failures (like the Delta Clipper’s hydrogen tank) are documented so mistakes aren’t remade or someone wants to pick up where NASA left off. Bigelow Aerospace acquired their expandable habitat design from a ‘low budget’ research program carried out at Johnson Space Center in just such a fashion.
tinker
No, the Delta Clipper was the McDonnell Douglas DC-X.
http://en.wikipedia.org/wik…
If they didn’t cancel it after it crashed landed, due to it’s landing leg giving away, it or it’s follow on was eventually going to enter nose first, flip upright and vertically land. During entry I think the plan was to have the engines running on idle too. Which is a similar flight profile to what SpaceX is planning if my understanding is correct. Hence my original question. They even were able to translate it to another landing spot in one flight.
What you are describing is the Venture Star.
http://en.wikipedia.org/wik…
Now I understand the disconnect in you answer.
Jack:
Sorry, you’re right. The X-31 SSTO was also nicknamed the Delta Clipper. I might even be thinking of Ben Bova’s fictional Delta Clipper from his ‘Moon Base’ books that was based on the X-31.
That said, my statement still applies. Regardless of the vehicle configuration, DC-X would have left solid data behind for others (maybe SpaceX) to follow up on. Even though we’d landed probes for decades on the Moon, Mars & Venus, DC-X was big and played in a much heavier gravity well. If anything it proved that powered landings on Earth could be controlled and predictable with the only major issue being engine reliability.
The last fifty years weren’t wasted by any means. We’ve learned a lot. I think it’s only been in the last ten years that we’ve really started to see folks really take advantage of that heritage.
tinker
You’re either thinking of the X-30 (NASP) or the X-33 (VentureStar). The X-31 was a thrust vectoring jet built for DARPA.
Paul:
X-33 (VentureStar). I Shoulda spent 3 seconds Googling that one! Just can’t keep all NASA’s cancelled projects straight anymore. 🙂
tinker
http://m.wacotrib.com/mobil…
Always something cooking in the oven 🙂 lololol
DTARS:
…and here’s the oven! From the latest tweet by Elon Musk:
https://twitter.com/elonmus…
tinker
The center engine is not much lower than the other eight lit ones. Do they plan to only fire the center one after booster seperation???????
DTARS:
The center one is the ‘Grasshopper’ engine that’ll be used for landing. As to how many will be used to slow it down? SpaceX said three, so it could be any three I guess. If the center engine fails, I don’t see why they couldn’t land on any outside opposing pair on deep throttle in a pinch. Imagine getting your stage back for repairs after an engine out event and still have a successful mission! I’m assuming that all the engines will still be gimbaled for just such eventualities.
tinker
It so obvious that this will work and a new age of space flight will start very soon.
SPACEX’s grasshopper does make me smile but SPACEX’s mission high light video still gives me goose bumps. I love the music and find to be comparable to the 2001 space odyssey theme
Oh, Ring of fire. Now I get it.