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The Grasshopper lifted to 24 stories (262.8 feet) off the ground

SpaceX took its reusable Grasshopper rocket for another hop last week at the South by Southwest festival in Texas.

SpaceX CEO Elon Musk was there to demonstrate the Grasshopper's fourth test flight, which was twice as high as the reusable rocket has ever gone in previous demonstrations.

"Grasshopper touched down with its most accurate thus far on the centermost part of the launch pad," said SpaceX. "At touchdown, the thrust-to-weight ratio of the vehicle was greater than one, proving a key landing algorithm for Falcon 9."

The Grasshopper lifted to 24 stories (262.8 feet) off the ground, hovered for about 34 seconds and then landed safely back on the ground.

The Grasshopper is a Falcon first stage with a landing gear that's capable of taking off and landing vertically. It does this by shooting into orbit, turning around, restarting the engine, heading back to the launch site, changing its direction and deploying the landing gear. The end result is a vertical landing.

The reusable rocket was tested in September, November, December and last week Thursday.

Check out this video of Thursday's demonstration:

Source: NBC News



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amazing
By Nortel on 3/11/2013 3:25:58 PM , Rating: 1
This is truly amazing and sad at the same time. Amazing because, seriously, it's a huge step for engineering. Sad... because it took a private citizen to completely fund this project.




RE: amazing
By rvd2008 on 3/11/13, Rating: -1
RE: amazing
By V-Money on 3/11/2013 9:07:10 PM , Rating: 4
quote:
...and where government is broke and barely paying its obligations...

If only they could earn trillions of dollars a year to pay their bills...it's not the fault of the 1% that the government can't budget. Hypothetically speaking if we took 100% of the money from the 1% and spent it towards our debt we would still have debt and then the government would get us right back to where we are within a couple of years, then who would you blame, the next 1%...douchebag


RE: amazing
By bupkus on 3/12/2013 12:57:27 PM , Rating: 2
Proof of concept?


RE: amazing
By JediJeb on 3/12/2013 10:47:03 PM , Rating: 5
A little searching and number crunching. If 1% of the current US population is multiplied by the mean net worth you end up with $51,518,412,246,000 (that is taking in all men, women and children: current census). Current budget is approximately $3.7T which means if you confiscate 100% of the wealth of the top 1% of Americans you can fund the government at current spending for 13.9 years. Subtract the current debt the US owes $16.4T and at current spending their wealth would fund the US government for 9.5 years. After that time unless those top 1% can re-earn that much money starting from $0 in 9.5 years you would not have that money to fund the government past that.

Now the next 19% of Americans could have their total worth confiscated and we would have another $76,300,787,754,000 which would fund the government for another 20 years.

So even if we took every dime from the top 20% of Americans we would pay off our debt and fund the government less than 30 years and leave 20% of our population broke and trying to rebuild their wealth.

Those numbers are based on total net worth not income. If we take 100% of only income from that group for a year we only pay for the government spending for 2 years without paying any of the debt. That 20% of people include everyone down to those making $226,000 per year and taking 100% of their income.

No matter how much we tax the rich we can never cover our spending by that alone. It will take taxing everyone down to those making a few dollars per year with a lemonade stand to cover our current spending level, or we just need to cut the amount of spending.


RE: amazing
By GotThumbs on 3/12/2013 9:56:41 AM , Rating: 2
Wow! Talk about having it wrong. You must be gulping the cool-aid.

The government's problem is they NEVER worry about costs, because they don't have to deal with investors or the drying up of investment money, so there's zero effort in operational efficiencies.

If it were not for the guaranteed revenues the government knows it will get and if it needs more....just raise tax rates, then the government would be a bankrupt business itself. If already can't support its wasteful spending.

People who have never run a business always like to blame the "rich", but there are many business owners who are not wealthy, but are able to build/run a profitable business. Not as many now-a-days due to the government trying to put the task of supporting all the out of work/lazy asses that have been on unemployment for multiple years.

A man takes responsibility...and child blames others. Obama is an adult child IMO.

Best wishes on taking care of your self.


RE: amazing
By GotThumbs on 3/12/2013 10:01:24 AM , Rating: 2
No offense to those who are truly trying to get back to work and being self-sufficient. Also, those who are truly disabled and unable to find work.

Problem is...there are way more people who could work, but choose to take the easy route...and they know who they are.

Best wishes for those trying to be self-supportive.


RE: amazing
By half_duplex on 3/12/13, Rating: 0
RE: amazing
By ameriman on 3/12/2013 10:15:12 PM , Rating: 2
The Govt is broke because it is a greedy, incompetent, wasteful, pork driven parasite..

Free enterprise provides us 100% of our goods/services, prosperity/strength...

Govt corrupts, bankrupts everything it touches..


RE: amazing
By Belard on 3/13/2013 5:09:27 PM , Rating: 2
UH... business corrupts govt. When you have people BUYING off elected officials... no?


RE: amazing
By Solandri on 3/11/2013 9:22:37 PM , Rating: 2
As far as reusable spacecraft go, the Space Shuttle had the right idea. You injected gobs of energy into the spacecraft to put it into orbit. Instead of bleeding it all off during descent, save some of it so you can glide to a landing.

I'm not sure what the goal of terrestrial rocket which lands upright is, aside from proof of concept. You're going to pump a lot of energy into it to put it into orbit. Then you're going to bleed all that energy off to get it out of orbit. Then you're going to use up more energy to bring it to a safe landing?

From an energy consumption standpoint, a glider landing or even a powered aerodynamic flight landing is preferable. Unless they've done calcs which say the energy cost of carrying the weight of the wings exceeds the energy cost of a powered landing. I suspect the most energy efficient way to travel to space and return is to take-off like a plane and fly to altitude, use rockets to get into orbit, use atmospheric drag to get out of orbit, then fly to a landing like a plane.


RE: amazing
By garidan on 3/11/2013 10:34:19 PM , Rating: 2
Wings are heavy and have no use to go up, they are air breaks even.
A rocket weights a lot, has it's own engines and doesn't need a plane which should anyway be very very big to lift it just to reach 20Km of height, on the way to 200km and beyond to orbit.

The beauty of the SpaceX plan is that all the weight you put for reuse is almost due to fuel, so that it becomes a safety margin too in case of problems at launch.
Do you have an engine out, you use more fuel and complete mission, and sacrifice that core for reuse.
And it scales very well for their Falcon Heavy, where they aim to use the same "technique" to recover the side boosters and core, something wings would not allow.

They are doing well, the first next launch with their new Falcon 1.1 rocket they'll test the first stage turn around (using cold gas) and reignition to break and try a "land" test on the ocean.
See NASA forum http://forum.nasaspaceflight.com/index.php?topic=2...


RE: amazing
By mjv.theory on 3/12/2013 5:00:21 AM , Rating: 2
quote:
As far as reusable spacecraft go, the Space Shuttle had the right idea.

I never saw the videos of the enormous external tank making an intact landing.

The fuel required to get 200miles up is only about 10% of the total. Most of the fuel is used to get to 7500m/s: orbital "velocity" - essentially you are not so much trying to go UP, as go FAST. This is what makes a staged rocket more mass efficient than a SSTO.

quote:
I suspect the most energy efficient way to travel to space and return is to take-off like a plane and fly to altitude, use rockets to get into orbit, use atmospheric drag to get out of orbit, then fly to a landing like a plane.

Using conventional rockets engines, this is incorrect. Something along the lines of Reaction Engines plans with Skylon, using their Sabre engines would be required. Also consider, wings are likely more of a liability during re-entry.

The fuel required to get 200miles up is only about 10-15% of the total. Most of the fuel is used to get to 7500m/s: orbital "velocity" - essentially you are not so much trying to go UP, as go FAST. This is what makes a staged rocket more mass efficient than a SSTO design (single stage to orbit). I suspect that a staged VTOL system like Falcon 9 might well also benefit from Sabre-like engines and eventually be the optimal solution.


RE: amazing
By JediJeb on 3/12/2013 10:58:13 PM , Rating: 2
Consider using this in places where there is no atmosphere for a glider to work(Moon, Mars to some extent, Jovian moons, ect) it would be the only way of landing and relaunching. It is definitely some good research for future projects.


RE: amazing
By delphinus100 on 3/15/2013 10:00:47 PM , Rating: 2
quote:
As far as reusable spacecraft go, the Space Shuttle had the right idea. You injected gobs of energy into the spacecraft to put it into orbit. Instead of bleeding it all off during descent, save some of it so you can glide to a landing.


Vertical landing concepts (not just a recoverable Falcon stage, this goes way back) don't try to decelerate all the way from LEO (it would take as much energy as to get there..and imagine putting a vehicle that big into orbit to begin with). Conventional aerobraking as we've always seen it, is done (after a retroburn that anyone must do, to dip the low point of your orbit into the atmosphere), until the vehicle slows itself to whatever its terminal velocity is. You need only enough propellant to decelerate from that to zero, and you air-start the engines at the right time to reach zero velocity at the surface.

What? Air-start of engines makes you nervous? The flip side is that a winged orbiter is a glider that must reach a runway of minimum length, and has only one pass st it.

Or go back to capsules whose parachutes must open properly, every time. (Soyuz-1, anyone?)

You pays your money and makes your choice...


RE: amazing
By mmatis on 3/12/2013 9:56:43 AM , Rating: 2
You might want to look at history from about twenty years ago:
http://en.wikipedia.org/wiki/McDonnell_Douglas_DC-...
DOD tried and there was no way to make it practical even with THEIR resources. This does not work for orbital vehicles due to mass fraction problems.


RE: amazing
By US56 on 3/12/2013 1:18:48 PM , Rating: 2
It's not a new concept or particularly amazing. The Douglas DC-X program started more than 20 years with a successful first flight a few years later. The last flight of the DC-XA achieved an altitude of 3,140 meters with a flight duration of 142 seconds. It only makes sense if operating on a planet or other celestial body with little or no atmosphere. Taking off from the surface of Earth, why carry oxidizer for the first stage when the atmosphere is ~21% oxygen? Why carry propellants for a descent when wings will work far more efficiently? The best means of achieving orbit from the surface of Earth for a small to intermediate payload mass such as astronauts with some equipment and supplies is probably a two-stage to orbit vehicle using a fly-back first stage booster and a winged orbiter. Unfortunately, U.S. military and space agencies have been gun shy about that approach since the tragic loss of a Lockheed M-21 in 1966. They would have to deal with the technical difficulties of separating two hypersonic vehicles at relatively low altitude (125,000-130,000 ft. ASL). Guessing that current computational fluid dynamics modeling techniques would render that problem somewhat less than intractable.


RE: amazing
By Bubbacub on 3/12/2013 4:37:29 PM , Rating: 2
wings add ~ 10% weight to a launch vehicle
a h2/02 rocket with a specific impulse of ~450 secs gives you a mass fraction of ~93% for an ssto.
thus for an ssto 93% of the weight of the fully fueled rocket must be propellant. the 7% includes , fuel tanks, engines, (wings!), re-entry system and oh the payload.

you dont need much propellant to land. even the space shuttle only gave the appearance of flying - it essentially had the aerodynamic properties of a brick and only really used the wings to generate lift and control its direction of flight in the last few minutes of sub sonic flight. the re-entry was a 95% ballistic.

thats a hell of a lot of weight to carry for very little in the way of payoff (other than the fact that it looks like an aeroplane and fools politicians into thinking that it will be cheap, safe and reliable).

the fuel to land a rocket that has slowed down to terminal velocity through atmospheric frcition takes up ~ 10% of the weight of the EMPTY rocket - a lot lot less than the weight of wings.

a winged rocket only really makes sense if they are used to generate lift during ascent.
gravity being what it is and the fixed specific impulse of chemical propellants mean that a conventional chemical rocket engine won't cut it.

thus to make a winged ssto work we need new technology - the skylon program will work - this uses atmospheric o2 during ascent to essentially give an advantageous specific impulse. this program looks very promising - however at the moment nobody seems to want to pay for its development.

another technology would be a nuclear thermal rocket. weight and greenpeace/ecomentalist issues make this difficult.

thus a winged ssto is going to need
1: some uber engineering to make a really light, really strong winged fuselage
2: some uber engineering to make novel propulsion systems
3: a bucket load of cash

the space x way has its issues, but there is little risk in terms of technology development and it is relatively cheap to develop (given that the falcon 9 production line is already up and running and paying for itself).


RE: amazing
By mmatis on 3/13/2013 9:23:53 AM , Rating: 2
Your mass fraction may work in theory, but in application it just ain't there. Lockheed Martin tried to go there with Venture Star, but as they got deeper into its design, the payload capability was -5000 pounds. And yes, that IS a minus sign in front.


RE: amazing
By patrickjchase on 3/14/2013 5:41:02 PM , Rating: 2
What makes you think that it "took a private citizen to do this"?

Have you ever seen the old Apollo lunar landing simulators from the 1960s?

http://en.wikipedia.org/wiki/Lunar_Landing_Researc...

For that matter how about the SDIO/Douglas DC-X prototype from the 90s?

http://en.wikipedia.org/wiki/McDonnell_Douglas_DC-...

The only thing that's surprising here is that it took private industry 50 years to get back to where Apollo was...


RE: amazing
By delphinus100 on 3/15/2013 10:07:31 PM , Rating: 2
Actually Blue Origin has been doing Grasshopper-like development for a while now, they're just more secretive about it. (one of them 'got away' last year, and exceeded the FAA permitted ceiling)

Armadillo and Masten, on a smaller scale (including mid-air shutdowns and re-starts, which the DC-X never got to, before a landing gear failure destroyed it) were doing VTVL development even longer...


RE: amazing
By patrickjchase on 3/14/2013 5:42:18 PM , Rating: 2
What makes you think that it "took a private citizen" to do this?

Have you ever seen the old Apollo lunar landing simulators from the 1960s?

http://en.wikipedia.org/wiki/Lunar_Landing_Researc...

For that matter how about the SDIO/Douglas DC-X prototype from the 90s?

http://en.wikipedia.org/wiki/McDonnell_Douglas_DC-...

The only thing that's surprising here is that it took private industry 50 years to get back to where Apollo was...


"The Space Elevator will be built about 50 years after everyone stops laughing" -- Sir Arthur C. Clarke

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