SpaceX Grasshopper Successfully Flies Sideways Before Returning To Landing Pad [VIDEO]
Source: International Business Times
The SpaceX Grasshopper, a new reusable rocket from the private spaceflight contractor, has set another milestone after launching vertically and then flying sideways for several hundred feet.
In the video released Thursday, the Grasshopper takes off vertically, reaching a height of 820 feet before hovering in the air and laterally shifting 330 feet. After it had successfully completed the maneuver, the Grasshopper safely returned to its landing platform. SpaceX, owned by billionare “hyperloop” pioneer Elon Musk, says that accomplishing such a maneuver is a big step forward in creating a truly reusable rocket.
"The test demonstrated the vehicle's ability to perform more aggressive steering maneuvers than have been attempted in previous flights. Grasshopper is taller than a ten story building, which makes the control problem particularly challenging. Diverts like this are an important part of the trajectory in order to land the rocket precisely back at the launch site after reentering from space at hypersonic velocity," SpaceX explained in a description alongside the video.
Such a maneuverable rocket is a unique idea, one that SpaceX hopes will be immensely useful -- and profitable -- for space agencies across the globe. SpaceX’s ultimate goal with the Grasshopper program is to create a rocket capable of vertically landing back on its launchpad after exiting and re-entering Earth’s atmosphere. The vast majority of rockets are simply discarded by spacecraft and left to burn up on re-entry. With a truly reusable rocket like the Grasshopper, SpaceX believes that space agencies would be able to save much time and money.
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Read more: http://www.ibtimes.com/spacex-grasshopper-successfully-flies-sideways-returning-landing-pad-video-1387943?ft=w14p5
= new reply since forum marked as read
Thanks for the thread, bananas. 
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The key, at least for the first stage, is the difference in speed. "It really comes down to what the staging Mach number would be," Musk says, referencing the speed the rocket would be traveling at separation. "For an expendable Falcon 9 rocket, that is around Mach 10. For a reusable Falcon 9, it is around Mach 6, depending on the mission." For the reusable version, the rocket must be traveling at a slower speed at separation because the burn must end early, preserving enough propellant to let the rocket fly back and land vertically. This also makes recovery easier because entry velocities are slower.
However, the slower speed also means that the upper stage of the Falcon rocket must supply more of the velocity needed to get to orbit, and that significantly reduces how much payload the rocket can lift into orbit. "The payload penalty for full and fast reusability versus an expendable version is roughly 40 percent," Musk says. "
But) propellant cost is less than 0.4 percent of the total flight cost. Even taking into account the payload reduction for reusability, the improvement is therefore theoretically over a hundred times."
A hundred times is an incredible gain. It would drop cost for Musk’s Falcon Heavy rocket—a scaled-up version of the Falcon 9 that’s currently rated at $1000 per pound to orbit—to just $10. "That, however, requires a very high flight rate, just like aircraft," Musk says. "At a low flight rate, the improvement is still probably around 50 percent. For Falcon Heavy, that would mean a price per pound to orbit of less than $500." Falcon Heavy is particularly amenable to reuse of the first stage—the two outer cores in particular, because they separate at a much lower velocity than the center one, being dropped off early in the flight.
Turnaround Time
Bringing down the cost of rocket launches isn’t just about reusability; as Musk’s quote suggests, it’s also about turnaround time. The original premise of the space shuttle program was that the vehicle would be turned around within days; it ended up being months, which is one of the reasons that it never met its cost goals.
What about a reusable Falcon? Musk says he expects "single-digit hours" between landing and next flight, at least for the lower stages. "For the upper stage, there is the additional constraint of the orbit ground track needing to overfly the landing pad, since cross-range (the distance to a landing site that it can fly to either side of its original entry flight path) is limited. At most this adds 24 hours to the upper-stage turnaround."
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So what does that mean for ticket prices in the future? Musk tells us that with daily flights, the cost will run about $100 per pound. For the average male, that means about 20,000 bucks. Start saving your money.
Revisiting SLS/Orion launch costs
by John Strickland
Monday, July 15, 2013
Comments (71)
A year and a half ago, I wrote an article very critical of the Space Launch System (see “The SLS: too expensive for exploration?”, The Space Review, November 28, 2011). To see if this assessment should now be updated, I checked a series of sources and found that little in the situation has changed, with no reliable cost estimates of an SLS launch yet available anywhere. It is actually amazing how hard it is to get cost estimates for any part of the SLS/Orion system. Another assessment corroborates this problem. While I was working on this article, two startling pieces of information came to light.
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A June 28, 2013, article in Space News, covering an official media tour of the Michoud plant and touting its new welding equipment, seems to indicate that NASA intends to fly the SLS only about once every four years even after the rocket’s development is completed. Previously the slowest launch rate anyone predicted was every two years. Even if NASA wants to fly the SLS more often, the cost of preparing new payloads for it may still greatly limit its flight rate. The Space News article quotes Steven Squyres, chairman of the NASA Advisory Council, as saying, “We have no experience with a human-rated flight system that only flies every two or three or four years.” This then brings into question the readiness of a launch team to do safe launches at rare intervals. This is a significant issue if you remember the problems of starting up shuttle launches again after the long launch gaps after the two shuttle accidents.
Information in another unofficial schedule posted on the Wikipedia page for the SLS (current as of July 1, 2013), indicates that NASA now does not plan to complete development of the 130-ton Block II version of the SLS until as late as 2030. Estimates of the payload up to those dates are between the initial 70 tons and up to 105 tons. This also implies a stretched out program and continuing development costs for another 15 or more years.
This information radically changes the assumed cost of each launch, since now, over a presumed 28-year lifespan, starting in perhaps 2022 and lasting presumably until 2050, the rocket would be used only seven times, and for more than a third of its lifespan, not able to launch the promised 130 tons. Its $30-billion development cost would then need to be divided among the few actual launches, not over all the years of the 28-year period, and would be about $4.3 billion per launch. This share of the launch cost represents money that could have been spend on payloads in years past. The per-launch cost of the rocket now jumps from $5 billion up to about $9 billion. The continuing annual cost of maintaining the workforce that allows launches to occur are rare intervals would need to be counted as part of each launch cost. The lesson learned from the Space Shuttle era is that the manpower costs are the largest cost, which is demonstrated again here. The cost table shown above now looks very different. Note that launch prices per ton and per pound for the initial 70-ton SLS version would be almost double that for the 130-ton version.
Revised bill for one SLS launch (one launch every 4 years):
Orion capsule with service module and escape system $1 billion
SLS first (core) stage, and upper stage $1 billion
Annual operating and launch facility maintenance costs $8 billion (cost over 4 years)
1/7 share of development cost $4.3 billion
TOTAL $14.3 billion cost per launch
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