Updates SpaceX Falcon 9 F5 CRS SpX-2 through CRS SpX-12 Updates

ISProgram

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They practically got to their target on the first go (ASDS) on the first go(!!). While it's unfortunate that the first stage didn't survive (intact), if they repeat a few more of these, regardless of whether or not the first stage survives on those attempts, it stills prove they can make a pinpoint landing.

And that is one step closer to be allowed to land back at CCAFS, which will make for a much better video. :)
 

PhantomCruiser

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Mission fail if the barge didn't sink?

The fact that they hit it at all should be pretty amazing.
 

Kyle

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They are doing undeniable progress in barge-sinking missles. Next time maybe ? :hmm:

.. would it be mean to call it the world's most accurate barge missile?

The lack of a first stage recovery is disappointing, but still -- Dragon made it to orbit and is on its way to ISS. Very positive news, especially after the Antares failure in October.
 

BrianJ

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They are doing undeniable progress in barge-sinking missles.
:)

Nicely done SpaceX! Interesting to hear the callouts for the 1st stage boost-back burn(later than my add-on version) and first reentry burn(earlier than mine). Awaiting more details/video of 1st stage "landing" with interest. Some screenies from my Orbiter "fly-along" :)

crs5_1.jpg

crs5_2.jpg

crs5_3.jpg

crs5_4.jpg
 

Urwumpe

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.. would it be mean to call it the world's most accurate barge missile?

Not really... after all even the chinese managed to turn one of their ICBMs into an intercontinental anti-ship missile, that should be able to hit an aircraft carrier without significantly slowing down...

That they managed to get close to the barge is a good achievement, but regarding the outcome, it would have been wiser to intentionally miss it and divert to a safe disposal area, than to push for a landing at all costs.

That they still failed to get good video data of the landing attempt is also no success at all.

It was a nice first try. It likely didn't cost SpaceX more than a few ten thousands of dollar for having to fix some superstructure parts of the barge, the stage wasn't expected to be of much (re-)use anyway. The lack of a few tons of possible payload on the launch wasn't a problem anyway, NASA will still pay well.

But I think the next landing should at least have much more engineering value. No problem if it intentionally misses the barge because it is still out of control on decision height or the engine is not restarting well. Its still much better to control the crash than to crash uncontrolled, especially as achievement for future operations. But primary goal should be getting all possible data of the flight and landing extracted, so even if it crashes, the next attempt will be improved on solid information and not post-mortem guess work on possibly interrupted telemetry streams or wreckage.
 

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Now that I have finished eating popcorn (really), since SpaceX has demonstrated it's close to recovering a first stage, how can the stage fly all the way back to the launch site? The only possible way to accomplish this seems to (nearly) enter orbit first.
 

Urwumpe

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Now that I have finished eating popcorn (really), since SpaceX has demonstrated it's close to recovering a first stage, how can the stage fly all the way back to the launch site? The only possible way to accomplish this seems to (nearly) enter orbit first.

It could also simply reserve more fuel for the fly-back maneuver after staging. After staging, the first stage is so much lighter, that a lot less fuel is needed for stopping and inverting the direction of flight. It would mean possibly that they need a less optimal ascent trajectory and the second stage would likely also need to give away some performance then.

But its possible. Its just not nice for the performance at all
 
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Unstung

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It could also simply reserve more fuel for the fly-back maneuver after staging. After staging, the first stage is so much lighter, that a lot less fuel is needed for stopping and inverting the direction of flight. It would mean possible that they need a less optimal ascent trajectory and the second stage would likely als need to give away from performance then.

But its possible. Its just not nice for the performance at all

I think that killing the horizontal velocity of the first stage and going back might require a lot more propellant than simply continuing onto an orbit that takes the rocket back over KSC. The problem with that is dealing with reentry. How expensive could it be for the stage to continue landing on the barge, or maybe in Europe, and just be transported across the ocean? It would save propellant and then the Falcon 9 can carry more per launch that way. Any way the rocket lands, SpaceX claiming that the rocket will not need to be refurbished after sounds crazy.
 

Urwumpe

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I think that killing the horizontal velocity of the first stage and going back might require a lot more propellant than simply continuing onto an orbit that takes the rocket back over KSC. The problem with that is dealing with reentry. How expensive could it be for the stage to continue landing on the barge, or maybe in Europe, and just be transported across the ocean? It would save propellant and then the Falcon 9 can carry more per launch that way. Any way the rocket lands, SpaceX claiming that the rocket will not need to be refurbished after sounds crazy.

What orbit? The first stage is on staging a few kilometers per second short from even doing a trans-atlantic landing - for doing an Orbit once around (including compensating for the fact that Earth rotates), you need a lot of more fuel than just turning around after about 4.5 km/s total impulse.
 

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What orbit? The first stage is on staging a few kilometers per second short from even doing a trans-atlantic landing - for doing an Orbit once around (including compensating for the fact that Earth rotates), you need a lot of more fuel than just turning around after about 4.5 km/s total impulse.

I was thinking in terms of shuttle abort modes and comparing the Falcon 9 to them. After three minutes, the time of staging for the Falcon 9, the space shuttle would have to land in Europe in the case of an emergency. The first stage doesn't get as close to entering orbit as I thought.
 

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They landed on it. Hard.

They performed a nice barge-braking assisted manoeuver (make the parallel with geobraking ;)).

Details on what happened during the rocket’s landing were not immediately known.
(Spaceflight Now)

Rocket made it to drone spaceport ship, but landed hard. Close, but no cigar this time. Bodes well for the future tho.
(Musk)

"Drone Spaceport Ship" = barge.
 

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Did it went overboard after landing?
If at least engine section managed to stay on barge then they will get a ton of useful data from taking it apart even if landing as whole was failure.
 

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Did it went overboard after landing?
If at least engine section managed to stay on barge then they will get a ton of useful data from taking it apart even if landing as whole was failure.

Since Musk is tweeting about "actual pieces", it sounds like it really crashed hard. But no details known yet, except a few small statements. a lot of the equipment on the barge had been damaged, so either the landing was a near miss (came close to the platform but landed outside the designated platform) or the rocket landed nearly unbraked.
 

ADSWNJ

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Two things I saw on the ascent video:

T+12:00 to T+12:40 ... man oh man what a gorgeous sunrise. Something for the D3D9 guys to drool over for sure!

T+12:56 ... debris floats by on deployment of the solar array?

On the attempted landing - it's for sure not a failure. It's a data gathering exercise taking then further on the way to creating a first for space flight (a reusable first stage). I salute their effort!! :salute:
 

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They are doing undeniable progress in barge-sinking missles. Next time maybe ? :hmm:

The barge did not sink did it? What good is a barge-sinking missile if it can't sink a damn barge?

What is this? a missile for saints? a failure should be at least 3-times more spectacular than this. ;)
 

Urwumpe

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T+12:56 ... debris floats by on deployment of the solar array?

Yes, thats pretty normal. You usually have protectors at such fragile deployable things, like solar arrays, to keeping secured during launch. On deployment, it depends in which kind of mission you are: If you are going to LEO, its tolerable to simply separate them (depending on the rest of your space debris). If you are deploying in MEO or GSO, you need to keep such protections on your spacecraft to prevent space debris.
 

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The fact that they hit it at all should be pretty amazing.

Can make same point about a kamikaze........
 

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The barge did not sink did it? What good is a barge-sinking missile if it can't sink a damn barge?

Hmm... I'd say that the projectile seriously lacks of penetration power. The idea is to make a hole in the deck down to the heel. So I'd recommend to reinforce the whole aft end with depleted uranium.
 

Urwumpe

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Hmm... I'd say that the projectile seriously lacks of penetration power. The idea is to make a hole in the deck down to the heel. So I'd recommend to reinforce the whole aft end with depleted uranium.

Much better would be diving below the barge at high speed and a rather shallow angle, so that the energy of the impactor is transfered to the water below the ship. If the impactor exceeds the speed of sound inside water this would create a large, quickly collapsing steam bubble that would break the structural neck of the barge.
 

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I really, really dislike the inability to hover for the Falcon 9R. With the method used now, it has to make its engine firing be precisely timed so that it reaches zero velocity with respect to the landing spot by the time it lands. This method does not allow fine alterations in case of changes in conditions by the time it reaches the landing point. These could be due to unexpected changes in winds, but in the case of a barge landing it becomes especially concerning with the rolling, pitching surface of a ship. From the description of this failed landing attempt, the first stage reached the barge but landed too roughly. A hovering capability would allow you to vary how gently you wanted the landing to be even under changing conditions.

The reason why the F9R can't hover is that even when throttled down as far as it can go, a single Merlin 1D still produces more thrust than the weight of the first stage when the stage is close to empty upon landing. However, there are some relatively low cost methods to give the F9R hovering capability:

They could replace the single central Merlin 1D with the Merlin 1A, which has lower thrust. They could use variable sized nozzles to alter the thrust. They could use inserts into the thrust plume that diverts the thrust horizontally. They could use the exhaust that comes only from the preburner, i.e., from the turbine exhaust nozzle visible to the left of the engine here:

47e74b892a3b9e58d2cf9aa917e68b12.jpg


Others?

Bob Clark
 
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