Space X: Oggi primo tentantivo di rientro ed atterraggio del primo stadio di un razzo

[Amati75]

SpaceX gears up to land a reusable rocket on a floating barge - and the breakthrough could make spaceflight more affordable for everyone

• SpaceX is planning to land a rocket at Cape Canaveral on Monday
• The first stage of their Falcon 9 rocket will attempt to touch down on a barge after launching a Dragon capsule into space
• It is the first ever attempt at landing a rocket on solid ground after launch
• Elon Musk said the ambitious attempt has a 50% chance of working
• The company ultimately wants all of its rockets to be reusable

SpaceX has long spoken of its ambition to make rockets reusable.
And on Monday, the firm plans to reach a major milestone as part of this endeavour when it brings back part of one of its Falcon 9 rockets after launch.
If all goes to plan, the first stage of the rocket will gently lower itself and land on solid ground for the first time ever.


The attempt will occur during the launch of the latest cargo-carrying Dragon capsule to the ISS at 7.31pm GMT (2.31pm EST) on Monday 16 December.
The Falcon 9 rocket carrying Dragon will take off from Florida’s Cape Canaveral Air Force Station.
After launch, at a height of about 56 miles (90km), the first stage of the rocket will separate from the second stage.
While the latter continues its mission into orbit, the former would usually be left to fall back into the ocean - as is the case on all other rocket launches.



However on this flight, for the first time ever, SpaceX will instead use a specially designed first stage capable of landing itself on a floating barge.
In a previous flight, a Falcon 9 first stage hovered above the surface of the ocean - without a barge - in a successful demonstration of the technology.
On that flight, the first stage was left to fall into the ocean after proving it could hover above the ground. But on this next flight, the rocket will touch down on a floating barge.


The barge measures about 300 feet (90 metres) long by 100 feet (30 metres) wide, and also has wings that extend out to another 170 feet (50 metres).
According to SpaceX chief Elon Musk, it also has ‘thrusters repurposed from deep sea oil rigs’ that can hold it in position within 10 feet (three metres) even in a storm.
To control the rocket as it lands, grid fins on its side are used, which control its pitch, yaw and roll.
These are ‘stowed on ascent and then deploy on re-entry for “X-Wing” [from Star Wars] style control,’ according to Musk.
And to slow it down as it descends it will save 15 per cent of its original fuel, allowing it to lower itself towards the ocean without the use of a parachute.



However, as the mission has never been tried before, he added that there was only a 50 per cent chances of the platform landing being a success on this first attempt.
Whatever the outcome, though, SpaceX will use the data they glean to improve their technique and one day plan to perform this manoeuvre during every launch.
Cameras on board the barge will capture the entire descent, although it’s unclear how much - if any - of this footage SpaceX will make public.
Eventually, they will start bringing the upper - or second - stage of the rocket back as well.
The ultimate goal is to make the entire rocket reusable - which will drastically reduce the cost of going to space.
SpaceX has a £1billion ($1.6 billion) contract with Nasa to resupply the ISS. This launch of the Dragon capsule will be the fifth of 12 scheduled missions.





http://www.dailymail.co.uk/sciencetech/article-2868769/SpaceX-gears-land-reusable-rocket-FLOATING-barge-breakthrough-make-spaceflight-affordable-everyone.html

[Second chance]

In pratica rientra planando invece che col paracadute. Perchè si sono complicati la vita in questo modo ? Solo per evitare il contatto con l'acqua ?

[Amati75]

In pratica rientra planando invece che col paracadute. Perchè si sono complicati la vita in questo modo ? Solo per evitare il contatto con l'acqua ?

Piu' "plananda", rientra atterrando, quindi rendendolo riutilizzabile, abbattendo quindi i costi.

[Second chance]

Piu' "plananda", rientra atterrando, quindi rendendolo riutilizzabile, abbattendo quindi i costi.

Ho capito, ma non potrebbero riutilizzarlo anche se ammarrasse con i paracadute ?

Edit: ho guardato sul sito della SpaceX; ci sono queste X-wings che regolano il trimming dello stage, ma non ho capito se ci sono anche dei thrusters o no per controllarne la velocità di discesa. A me continua a sembrare una planata, più che un atterraggio controllato. Boh.

[Amati75]

Ho capito, ma non potrebbero riutilizzarlo anche se ammarrasse con i paracadute ?

Evidentemente vi è qualche differenza visto che anche l capsule di rientro, che rientrano con il paracadute sono monouso.
Quale essa sia non è ho idea.


Sent from my iPhone using Tapatalk

[paulhowe]

Ho capito, ma non potrebbero riutilizzarlo anche se ammarrasse con i paracadute ?

Il razzo non deve "ammarare", ma riatterra su di una piattaforma senza toccare l'acqua. Questo e' lo schema







In pratica il razzo atterra su questa chiatta






Si tratta di un operazione molto complessa, mai tentata prima.

[Second chance]

Evidentemente vi è qualche differenza visto che anche l capsule di rientro, che rientrano con il paracadute sono monouso.
Quale essa sia non è ho idea.


Sent from my iPhone using Tapatalk

Eh, scusa. Nel frattempo avevo editato il mio messaggio precedente. Sorry.

[Second chance]

Il razzo non deve "ammarare", ma riatterra su di una piattaforma senza toccare l'acqua. Questo e' lo schema







In pratica il razzo atterra su questa chiatta






Si tratta di un operazione molto complessa, mai tentata prima.

Grazie per la spiegazione. Dal tuo schema sembra che siano utilizzati dei thrusters in rientro; nel sito della SpaceX non sembra così evidente.

[Amati75]

Musk’s SpaceX to Test Reusable Rocket for Mars Missions

By Julie Johnsson Jan 5, 2015 2:19 PM ET 15 Comments Email Print

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Photographer: Chris Thompson/SpaceX via BloombergSpace Exploration Technologies Corp.'s (SpaceX) Falcon 9 rocket takes off in Cape... Read More

Billionaire entrepreneur Elon Musk is developing rockets that could be reused, rather than burn up on re-entry to earth’s atmosphere, in the belief they’ll drastically reduce the cost of trips to Mars.
He could make history -- and remake the space launch sector -- when new technology that captures spent rocket segments is put to the test for the first time tomorrow.
Musk’s Space Exploration Technologies Corp. will try to land a Falcon 9 rocket atop an unanchored ocean platform bobbing in the Atlantic Ocean after the missile propels a cargo capsule towards a rendezvous with the International Space Station.
“It could potentially be a significant breakthrough,” said Marco Caceres, director of space studies with Teal Group, a Fairfax, Virginia-based consultant. “It’s even more significant if it occurs with the program that is already known to be significantly cheaper” than competing launch vehicles.
Rocket-makers from France’s Arianespace SA to United Launch Alliance, a Boeing Co (BA).-Lockheed Martin Corp. (LMT) venture, are already streamlining operations to compete with SpaceX’s $61.2 million price for Falcon 9 launches, the industry’s lowest, Caceres said in a phone interview. Reusing the rocket’s Merlin engines and aluminum-lithium alloy structure would drive costs down further. Musk has said that developing a reusable rocket could cut the cost of spaceflight by afactor of 100.
Photographer: Simon Dawson/BloombergBillionaire Entrepreneur Elon Musk’s Space Exploration Technologies Corp. will try to...Read More

First Musk’s concepts have to work, however. The odds of success on tomorrow’s first mission to retrieve the rocket “are not great -- perhaps 50 percent at best,” SpaceX said in a description of the flight on its website.
NASA Commission

Musk will hold an online question-and-answer session via the reddit message board tonight at 9 p.m. Florida time, focused on the rocket launch.
SpaceX plans to launch the two-stage rocket and cargo commissioned by the National Aeronautics and Space Administration from Florida’s Cape Canaveralat 6:20 a.m. local time.
About 157 seconds into flight, when the Falcon 9 is more than 50 miles (80 kilometers) high and traveling more than 10 times the speed of sound, the craft’s main engines will shut down. Four seconds later, the first and second stages will separate.
To help stabilize the 14-story tall first stage during its return to earth, SpaceX plans to relight the engine for a series of three burns.
The first burn will adjust the rocket segment for the correct point of impact, followed by a “supersonic retro propulsion burn” that along with the drag of the atmosphere will slow its speed from 1,300 meters per second (almost 1 mile per second) to about 250 meters per second, according to SpaceX’s website.
Giant X

Four legs will deploy during a final landing burn as the vehicle’s speed slows to about two meters per second. SpaceX also plans to use four grid fins to help control and steer the Falcon 9 as it targets a barge festooned with a bullseye and giant X.
SpaceX, based in Hawthorne, California, has little margin for error. The floating platform measures 300 feet (91 meters) by 170 feet; the rocket’s legs span 70 feet.
While the space venture successfully guided rockets to soft water landings twice last year, “we could only expect a landing accuracy” of about 10 kilometers, SpaceX said. “For this attempt, we’re targeting a landing accuracy of within 10 meters.”
Any failure could be magnified, Caceres said. Tomorrow’s launch will be high-profile as the first cargo resupply mission since an Antares rocket operated by Orbital Sciences Corp. exploded in a fireball in October.
“That they’re willing to do this with a relatively unproven technology is pretty gutsy,” Caceres said. “He’s willing to take his chances.”
‘We’re Close’

Tory Bruno, president and chief executive officer of the United Launch Alliance, isn’t convinced the technology is mature, or that there’s adequate payoff for the extra fuel and thicker structure required to guide the craft back to earth.
“You’re asking the expendable launch guy what he thinks about reusable engines,” Bruno said during a Nov. 13 address at the Atlantic Council in Washington, D.C. “Their time will come. It’s not here yet.”
Musk is confident that SpaceX will succeed, if not tomorrow, then on one of the dozen launches planned over the next year.
“We’re close,” he told an audience at the Massachusetts Institute of Technology in October.
To contact the reporter on this story: Julie Johnsson in Chicago at jjohnsson@bloomberg.net
To contact the editors responsible for this story: Ed Dufner at edufner@bloomberg.net Molly Schuetz, Bruce Rule

Musk?s SpaceX to Test Reusable Rocket for Mars Missions - Bloomberg

[paulhowe]

Nei prossimi 12 mesi dovrebbero fare 17 (!!) lanci compreso il Falcon Heavy, di fatti il piu potente lanciatore del mondo.

SpaceX Could Launch 17 Rockets in 2015, Including the Most Powerful Rocket Since Saturn V