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SpaceX Successfully Lands Two Falcon Heavy Boosters Simultaneously After Rocket Launch [Update] (spaceflightnow.com)
After nearly a decade of development, SpaceX's Falcon Heavy rocket has successfully launched from pad 39A at NASA's Kennedy Space Center in Florida today. After reaching orbit, the two side boosters simultaneously landed at Landing Zone One. We do not know the status of the central core of the rocket, which was destined to land on the "Of Course I Still Love You" drone ship roughly 8:19 minutes into the flight.
According to Space.com, the Falcon Heavy is the most powerful rocket to launch since NASA's Saturn V -- the iconic vessel that, with 7.5 million pounds of thrust, accomplished the definitive Apollo-era feat of putting astronauts on the moon. Elon Musk says that Falcon Heavy is "twice as powerful as any other booster operating today." As for the payload, it includes a Tesla Roadster electric car. "The Falcon Heavy will send the vehicle around the sun in an elliptical orbit that will extend farther than Mars' orbit," reports Space.com.
UPDATE: SpaceX has confirmed The Verge's reporting that the middle core of SpaceX's Heavy Rocket missed the drone ship where it was supposed to land. "The center core was only able to relight one of the three engines necessary to land, and so it hit the water at 300 miles per hour," reports The Verge. "Two engines on the drone ship were taken out when it crashed, SpaceX CEO Elon Musk said in a press call after the rocket launch. It's a small hiccup in an otherwise successful first flight."
According to Space.com, the Falcon Heavy is the most powerful rocket to launch since NASA's Saturn V -- the iconic vessel that, with 7.5 million pounds of thrust, accomplished the definitive Apollo-era feat of putting astronauts on the moon. Elon Musk says that Falcon Heavy is "twice as powerful as any other booster operating today." As for the payload, it includes a Tesla Roadster electric car. "The Falcon Heavy will send the vehicle around the sun in an elliptical orbit that will extend farther than Mars' orbit," reports Space.com.
UPDATE: SpaceX has confirmed The Verge's reporting that the middle core of SpaceX's Heavy Rocket missed the drone ship where it was supposed to land. "The center core was only able to relight one of the three engines necessary to land, and so it hit the water at 300 miles per hour," reports The Verge. "Two engines on the drone ship were taken out when it crashed, SpaceX CEO Elon Musk said in a press call after the rocket launch. It's a small hiccup in an otherwise successful first flight."
That I had to double-check that I was watching a live stream and not a CGI of what they expected to happen.
What a shitty Slashdot summary for such an important event!
Don't bother reading that shitty article. Just go to SpaceX's website directly, where there is video footage. Or look at the SpaceX tweets.
Yes. Perfect platform on water landing.
Fucking A, that was awesome!
BlameBillCosby.com
https://www.youtube.com/watch?v=-B_tWbjFIGI&feature=youtu.be&t=2299
Why would it suspiciously be cut short? Elon Musk actively celebrates the learned experiences of failure when rockets blow up. He was even joking around yesterday that if the entire mission was a failure with the entire thing exploding (the entire heavy, not just the central booster), that it would still be an awesome experience.
It is hard to make a rocket nozzle that works well in the atmosphere and in space.
Yes! This is one of the reasons for staging. The first stage engines are optimized for atmospheric use and the upper stage for vacuum or near vacuum conditions. In the case of the Falcon Heavy, the first stage uses 27 Merlin 1D engines https://en.wikipedia.org/wiki/Merlin_(rocket_engine_family)#Merlin_1D, and the upper stage uses a single vacuum optimized Merlin 1 https://en.wikipedia.org/wiki/Merlin_(rocket_engine_family)#Merlin_1D_Vacuum. This isn't the only reason for staging (all that extra mass from carrying extra storage tanks for empty fuel and oxygen is another big one) but it is a major one.
With that many engines to steer, I wonder if there is some way to use the extra degrees of freedom to shape the plume to get a bit more thrust?
I don't have a source for this off-hand, but given my understanding my guess is going to be no. Almost all the things that happen to alter the thrust profile occur in the engine itself or immediately outside the engine. Anything you would do that could have any chance at this would end up having to have multiple outer engines pointing somewhat inwards which would mean you'd have some thrust canceling out from the outer engines. Anything you could gain by somehow altering the profile of the inner engines wouldn't be remotely worth losing thrust that way. If more containment would give more thrust in some range, you'd just build your engine with a longer nozzle.
Here is a tweet with a view of monitors showing smoke clearing from the drone ship deck with no rocket aboard. It seems it missed the ship. Not too surprising as the centre core is a new machine that has never flown before. Also, the re-entry profile was likely one of the hottest ones they have tried.
This and no other is the root from which a tyrant springs; when first he appears as a protector - Plato (423 to 327 BC)
Just hear it hear from spacex stream itself: https://www.youtube.com/watch?v=-B_tWbjFIGI&feature=youtu.be&t=2310
Not at all - all the first-stage boosters use atmosphere-optimized engines that also work pretty well in space. But you'll notice that the single second-stage engine has a much larger bell, almost as large as those from the 9 first-stage engines combined - that's to optimize it for vacuum, which gives it a nice efficiency boost.
Basically, when designing the engine you have to pick the ambient pressure to optimize for - at that pressure it will burn as powerfully efficiently as possible, with effectiveness dropping as pressure changes in either direction - typically first stage engines are optimized for high power somewhere in the mid-to-high atmosphere, where they spend most of their time, while second stages are optimized for efficiency in full vacuum, since they don't need the raw power for liftoff, or to ever deal with an atmosphere.
I would assume there's also other optimizations that can be done to reduce efficiency falloff as pressure changes, but they almost certainly come at the expense of lower peak performance, so it's a balancing game.
As for trying to shape the first-stage plume by vectoring the engines - it might be possible, but is unlikely to show any gains. You need to keep two things in mind:
1: Any vectoring will, by necessity, be trading forward thrust for lateral vectoring effect
2: By the time the plume leaves the bell, it's basically stopped pushing the rocket forward - the rocket isn't actually propelled by the gasses shooting out the back - it's propelled by those by those rapidly-expanding gasses bouncing off the engine and bell as they expand. Once they leave the engine bell they no longer have any effect on the rocket at all (except possibly indirectly through fluid-dynamics effects on the surrounding atmosphere.
Combine the two, and you'd have to pull off some pretty impressive fluid-dynamic miracles to even manage to break even. And even assuming you somehow managed that, it would almost certainly become impossible as you exceeded the speed of sound (aka the speed at which atmospheric disruptions can propagate)
Here's a good photo of what's basically going on - the bell is designed to contain the engine exhaust until it falls to ambient pressure and stops expanding, at which point no more work can be extracted from it. Too big, and the atmospheric pressure pushes the plume away from the bell, and you lose thrust to turbulence losses and wasted mass worth of useless bell. Too small, and the gas is still expanding when it leaves the bell, and you're throwing away all the work that could have still been done. Obviously in a vacuum that gas is going to keep expanding essentially forever, but the more it expands, the less remaining work it can do, and the faster the size (and mass) of a containing bell will increase. So at some point the diminishing returns just aren't worth pursuing any further.
https://i.stack.imgur.com/cJ4e...
--- Most topics have many sides worth arguing, allow me to take one opposite you.
You can hear them say the core stage was "lost" on the second feed (control room feed), but it's not clear to me if they meant [i]destroyed[/i] or [i]lost telemetry[/i].
Over 64% of the company, Arianespace, is from France. Germany is the next highest percentage, with just under 20%.
Confirmed at the news conference. Not enough fuel left on the central core; only one of the three engines managed to relight, and the stage hit the water at 300mph. However, SpaceX not only didn't plan not to use the central core again, but doesn't plan to use the side boosters either; they're not Block 5, and SpaceX only plans to re-launch Block 5 from now on. That said, the side boosters appear to be in good shape.
The main concern right now is on the upper stage. They've never had a stage dwell so long in such a high radiation flux. It should re-light, but they won't know until they try.
It's time for Operation Crazy Plan.
In the press conference today he said he's hoping that the cameras on the drone ship turn out to be intact, he expects there to be some good explosion footage on them ;) I love how it always gets posted.
One interesting thing from the press conference: of all of the parts of the rocket, he's most pleased to get the titanium grid fins on the boosters back. The central core didn't have the new grid fins, but the boosters did - and they're very expensive, and currently a production bottleneck for them.
It's time for Operation Crazy Plan.
Space Shuttle booster recovery was about recovering scrap metal. It's not remotely comparable to recovering something that you could (if you wanted to) refuel and send back upward in 10 minutes.
The re-usability of the Dragon spacecraft, on the other hand, is much less novel.
This space intentionally left blank
The plans Changed. Musk said on the media interview that they were NOT going to man rate FH because BFR will be ready much sooner than they thought and it will handle the moon. It sounds like end of 2019.
I prefer the "u" in honour as it seems to be missing these days.
Musk said there's a towel in the glove box, too!
This Starman is well prepared for whatever might come.
You actually did see it. They had a feed from the deck of the drone ship which went from clear to what looked like a steam room in a split second.
https://www.youtube.com/watch?...
That's what I guess you see when something hits the water at 300 mph.
Slight correction: the core ran out of ignition fluid (a mix of triethylborane and triethylaluminum, ignites on contact with LOX (or most anything, really)), not fuel. A similar setup was used for both the Saturn V's F-1 engines, and the SR-71's J58 engines.
And a status update: the second stage re-lit just fine, and in fact exceeded expectations - the aphelion of the orbit is well past Mars, just shy of Ceres in fact.