SpaceX Falcon 9R launch

JoshNH4H · 2014-04-14 12:51:38

SpaceX is testing their reusable Falcon 9R today. The launch is at 16:58 EST, from Cape Canaveral.

Live feed can be found here.

For live chat about the launch, go to webchat.freenode.net. Enter a nickname, fill out the catchpa, and once you hit connect type "/join #newmars" into the bar at the bottom, then hit "enter". I'll be there and I'm sure a couple others will be too!

Terraformer · 2014-04-14 15:40:14

Alas, it got scrubbed because of a helium leak...

JoshNH4H · 2014-04-14 15:52:18

Quite unfortunate, and they're predicting a scrub for weather on Friday too.

GW Johnson · 2014-04-17 18:14:58

I talked to a Spacex McGregor technician today at the local auto parts store. He told me the test I heard yesterday was their Grasshopper test vehicle flying with the production design composite landing leg assembly that is on the Falcon-9 at the Cape. That flight verified structural integrity of the flightweight legs for an actual touchdown on solid land, which is not what will happen on the upcoming launch. They're just trying to get a splashdown survivable enough to recover hardware for evaluation.

I saw some words somewhere that indicated there was something "special" about this Dragon, too. Although, I have been unable to locate those words again. The photos do not show anything I recognize as the Super Draco thruster assemblies, which bulge outward a lot more than the standard Draco thruster units. They've been testing those Super Dracos as separate items for some time now. I'd think they'd want to pre-test them on a flight they're getting paid to make anyway, but maybe the NASA contract specifies otherwise. I did not ask the tech about that.

I did ask him about the new thrust stand for Falcon-Heavy. He said the concrete, much (but not all) the steel, and the water supply system for the sound-deadening water curtain, are in place. They hope to test a Heavy on it by year's end, but there's a lot of thrust stand steel still to install. They gotta get it done soon, as USAF wanted them to launch a Heavy from Vandenburg sometime this year. I think that launch date will slip, although the web site did not reflect that, last time I looked several days ago.

GW

GW Johnson · 2014-04-18 19:32:02

News reports today show (1) successful launch, (2) successful injection of Dragon onto orbit, targeted for rendezvous with ISS Sunday, and (3) data received from 1st stage of Falcon-9R for 8 seconds after (after !!!!) landing in the Atlantic.

Congrats to Spacex!!! Very, very, very well done!!!

GW

RobertDyck · 2014-04-18 20:25:08

And this like came through the Mars Society DC email list. Successful test of Falcon 9R.
https://m.youtube.com/watch?v=0UjWqQPWmsY

JoshNH4H · 2014-04-19 15:22:48

I'm excited to find out what the telemetry from the landing said, with regards to how quickly the stage was moving when it hit the water, and what SpaceX has to say regarding how fast is slow enough.

Quaoar · 2014-04-21 03:37:13

JoshNH4H wrote:

I'm excited to find out what the telemetry from the landing said, with regards to how quickly the stage was moving when it hit the water, and what SpaceX has to say regarding how fast is slow enough.

Having landing legs, Falcon 9R will not need launchpad: is it correct?
If so, another big cost will be cut.

RobertDyck · 2014-04-21 04:11:54

Quaoar wrote:

Having landing legs, Falcon 9R will not need launchpad: is it correct?
If so, another big cost will be cut.

Unfortunately, no. Falcon 9R is designed to launch with its legs folded up. That way it's streamlined for hypersonic speed through the air. The legs unfold when landing. The test was done with legs unfolded, but that's not how it will launch.

The current flight, CRS3, launched with the legs. YouTube video of the launch here. Start watching 37 minutes in.
http://www.youtube.com/watch?v=Od-lON4bTyQ

SpaceNut · 2014-04-21 17:34:29

Sea crew to attempt retrieval of Falcon 9 first stage

SpaceX is careful to describe the attempted first stage recovery as an "experiment," giving the chance of a fully intact retrieval at just 30 or 40 percent. The rocket is fitted with four landing legs made of carbon fiber and aluminum honeycomb. The 25-foot-tall legs will extend down and outward, deploying during the first stage's descent.

Four carbon fiber and aluminum honeycomb mounting legs mounted around the base of the 12-foot-diameter first stage were supposed to extend shortly before the water landing.

http://spaceflightnow.com/falcon9/009/1 … usability/

The first step was to prove the rocket's first stage could complete a series of unprecedented engine burns using leftover propellant after finishing its primary job of boosting a satellite into orbit. The first stage was supposed to fire its engines twice after separating from the Falcon 9 rocket's second stage less than 3 minutes after liftoff Friday. The first burn was expected to slow the rocket's velocity enough to fall into a prescribed landing zone in the Atlantic Ocean a few hundred miles northeast of Cape Canaveral, and a second firing was to have allowed the rocket to gently settle into the sea.

JoshNH4H · 2014-04-21 19:33:49

First stage reusability by the end of 2014! What news! What this really shows,I think, is all the unnecessary bloat in NASA's usual contractors.

SpaceNut · 2014-04-21 20:34:31

Well procurement of materials not only to make parts from but to purchase from outside sources process through military sources are quite expensive and then add to it unions it adds up to a pretty penny.

Tom Kalbfus · 2014-04-21 21:04:22

RobertDyck wrote:

Quaoar wrote:
Having landing legs, Falcon 9R will not need launchpad: is it correct?
If so, another big cost will be cut.
Unfortunately, no. Falcon 9R is designed to launch with its legs folded up. That way it's streamlined for hypersonic speed through the air. The legs unfold when landing. The test was done with legs unfolded, but that's not how it will launch.
The current flight, CRS3, launched with the legs. YouTube video of the launch here. Start watching 37 minutes in.
http://www.youtube.com/watch?v=Od-lON4bTyQ

So the legs weren't designed to retract after launch? You think there are other applications for landable rockets. Suppose we had a reusable rocket that can go into space and land in its tail? That is just go above the atmosphere for a few minutes then drop back down and land on its tail, and with a little maintenance it would be ready for relaunch. One possible idea would be a troop transport for the Army or marines, a rocket soars above the atmosphere and lands somewhere a few hundred to a thousand miles from where it had launched. Rockets can be more reliable that airplanes since they can operate in space, they can fly over instead of through weather, if can fly over some hostile country's airspace instead of through that airspace.

RobertDyck · 2014-04-22 07:14:42

Tom, now you're here. Rockets consume a hell of a lot of fuel. They have short range, and have to be built rediculously light and flimsy just to work at all. Notice Falcon 9 v1.1 is much larger than Falcon 9. That's so it can lift landing legs, so it has enough fuel to land, and so its tanks have enough additional structural strength that they can be used more than once. All that takes mass, and lifting that mass requires additional fuel. Now compare the size of the Falcon 9 v1.1 first stage to Dragon. Do you realize how big that is? Now compare the fuel tanks of a V-22 Osprey to it's cargo hold and cockpit. Do you still think rockets can compete with air breathing engines?

GW Johnson · 2014-04-22 08:57:29

Tom's suggestion of rocket troops sounds fairly ridiculous today. RobertDyck correctly pointed out the reasons why.

Yet, surprisingly enough, in the late 1950's and early 1960's, exactly that rocket troop thing was one potential mission for a new giant ICBM development being done by the US Army. They were using the ex-German scientists from Operation Paperclip for this, so you know who the chief designer was. This started before there ever was a NASA, which was created out of the older NACA in 1958, and charged with a civil space program, separate from military efforts of various sorts that were ongoing in USAF, USN, and US Army.

What you may not know is that "giant ICBM" of the US Army was the Saturn family of rockets. Those were NOT originally designed to be space launch or moon rockets, contrary to popular belief today. The Apollo moon mission had to be adapted to the biggest rockets then potentially available. That's why NASA had to accept the outside-the-agency idea of lunar orbit rendezvous in order to get down to one Saturn-5 launch per moon mission. NASA has never accepted an outside-the-agency idea since, but now may have to, since Spacex is showing them up, so very adroitly.

The mid-50's concept of the rocket troop mission was a pre-emptive strike on the Soviet Union. Saturn-1's dispensing "bombs" of LSD-25 would put everybody out on their backs, seeing pretty colors for three days, followed by Saturn-5's as a 2-stage vehicle bringing over 100-man battle units in big parachute/rocket brake landing canisters (a one-way trip). The idea was to be standing there with bayonets at their throats when everybody woke up from the LSD trip. (Of course, this would have been a fleet of giant rockets that would have made the 1970's ICBM fleet look like a bathtub toy flotilla.)

I know this sounds like the plot to a very bad sci fi story, but it was very, very real in the late 1950's. This is the real genesis of the Saturn-5 moon rocket. It is what Werner von Braun was working on, before he got to do what he really wanted: go to the moon with giant rockets.

If there is anything to be learned from a story like that, it is that government agencies are not renowned for their common sense.

GW

JoshNH4H · 2014-04-22 10:54:36

Do you know if there are public domain records about that stuff? There's some fertile ground for alternate history there.

GW Johnson · 2014-04-22 12:03:49

It should have been well-recorded in the aerospace trade magazines of the time. I'm not sure Aviation Week goes back to the 50's. But there was a magazine like that back then. I think it was called "Western Aerospace" or something very similar.

GW

JoshNH4H · 2014-04-22 14:22:40

I'll look into that, thanks.

The idea of reusable launchers is much more relevant on, say, the Moon or Mars than on Earth, IMO. Because of Earth's stronger gravity, reusability (and specifically the reusability where you land, refuel, and relaunch like a car or plane (actually I guess this is most comparable to how a boat works...) it's very difficult to get the kinds of structural fractions that you need for this to work. But on the Moon or Mars, the delta-V to do an orbital round trip is in the vicinity of 4.0 or 4.25 km/s, respectively (aerobraking assumed for Mars), you can get your mass ratios pretty reasonable. Assuming Hydrogen fuel, that's a mass ratio of about 2.5 or about 2.75 (dry mass fractions of .4 or .35 respectively). That's really not bad, very doable in fact. We'd be jumping with joy to have those on Earth*.

Design of a reusable launcher/lander for Mars or the Moon is going to be somewhat different than for Earth. For starters, the entire vehicle will have significantly lower thrust-to-weight. It will probably not be very aerodynamic, with heat shields that are not retractable thanks to the thin-to-nonexistent atmospheres. On Mars Olympus Mons is certainly worth considering as a launch site, seeing as the pressure at the top of Olympus corresponds to the pressure at 65 km on Earth, e.g. pretty negligible.

They will also have low-thrust-to-weight, low operating pressure engines. This will mean simpler or even nonexistent turbopumps (I really do think that pressure-fed is reasonable in this regime), less need for cooling (if your engine is only operating at 5-10 atm internal pressure, it can have correspondingly less structural mass and therefore improved heat transfer properties. Further, at lower pressure you will have less "stuff" in the combustion chamber at any given time and therefore a lower heat rate per unit volume). If SpaceX's technology demonstrations are anything to go by, they will probably have landing legs.

Obviously the engines will need to be restartable. That means some kind of spark ignition, ideally. Because the pressurization is not nearly as high as in Terran rockets (the SSME operated at 200 atmospheres) much less energy will be wasted on inefficient pressurization. In fact, more energy is lost pressurizing to 200 atmospheres at 80 percent efficiency than 10 atmospheres at 20% efficiency. That means no turbopump, most likely, or if one is used we can settle on a simpler, less efficient one with wider design tolerances. A pump pressurizing to 10 atmospheres at 50% efficiency wastes the same amount of energy as one pressurizing to 200 atmospheres at 95% efficieny, and because of the low pressure external environment the engines can have the same exhaust velocity.

*A mass ratio on Earth of 2.75 would correspond to an exhaust velocity of approximately 10 km/s. Let (s)he among us who is without envy launch the first rocket!

Tom Kalbfus · 2014-04-22 16:26:09

I can think of one application. Tourism on Mount Everest. Helicopters can't fly that high, but a reusable rocket could. Not everyone is cut out to make the climb with Sherpa guides, but imagine blasting off on a rocket and landing on Everest's summit.

RobertDyck · 2014-04-22 16:45:13

That would defeat the point of Everest. It's supposed to be hard.

JoshNH4H · 2014-04-22 18:07:28

"It's supposed to be hard" is not an argument that holds much (any?) sway in our society. If there's money to be made, it will happen.

Mount Everest, at a bit under 9 km (30,000 ft) above sea level, could easily be reached with commercial airplanes. The 777 can fly at up to 13,000 km (40,000 ft), so it's not too difficult to imagine that some kind of airplane (perhaps modified with rocket thrusters so that it can take off vertically, thus requiring a shorter runway) could do it.

RobertDyck · 2014-04-22 18:44:12

You could build a runway. Workers with continuous oxygen. Make the oxygen last longer with a rebreather. Just climb the mountain with heavy equipment. May require blasting and road building along the way to get equipment up there. Don't know about engines at altitude, but as you pointed out, aircraft can do it. Heavy equipment can log the rockies.

SpaceNut · 2014-04-22 19:48:47

Isn't it time to get back to the topic Reusable Rockets to Orbit Just an older topic on the nuts and bolts to make it happen.

JoshNH4H · 2014-04-22 20:45:00

I think we're talking more about vertical takeoff and landing in general at the moment.

Anyway, I would expect building a runway would be quite expensive, and that's why I suggested rocket based vertical takeoff and landing. It's not like we're building cities up there.

Tom Kalbfus · 2014-04-22 21:41:54

RobertDyck wrote:

That would defeat the point of Everest. It's supposed to be hard.

How about rescuing injured climbers? A medical helicopter can get up there, a 747 can't hover and land there, a rocket could. Perhaps something like a sky crane could be used. Today if a person can't make it down by himself and no one can carry him, he is left to die, as no helicopter can be sent to rescue him as it is beyond their operational ceiling.

New Mars Forums

Announcement

#1 2014-04-14 12:51:38

SpaceX Falcon 9R launch

#2 2014-04-14 15:40:14

Re: SpaceX Falcon 9R launch

#3 2014-04-14 15:52:18

Re: SpaceX Falcon 9R launch

#4 2014-04-17 18:14:58

Re: SpaceX Falcon 9R launch

#5 2014-04-18 19:32:02

Re: SpaceX Falcon 9R launch

#6 2014-04-18 20:25:08

Re: SpaceX Falcon 9R launch

#7 2014-04-19 15:22:48

Re: SpaceX Falcon 9R launch

#8 2014-04-21 03:37:13

Re: SpaceX Falcon 9R launch

#9 2014-04-21 04:11:54

Re: SpaceX Falcon 9R launch

#10 2014-04-21 17:34:29

Re: SpaceX Falcon 9R launch

#11 2014-04-21 19:33:49

Re: SpaceX Falcon 9R launch

#12 2014-04-21 20:34:31

Re: SpaceX Falcon 9R launch

#13 2014-04-21 21:04:22

Re: SpaceX Falcon 9R launch

#14 2014-04-22 07:14:42

Re: SpaceX Falcon 9R launch

#15 2014-04-22 08:57:29

Re: SpaceX Falcon 9R launch

#16 2014-04-22 10:54:36

Re: SpaceX Falcon 9R launch

#17 2014-04-22 12:03:49

Re: SpaceX Falcon 9R launch

#18 2014-04-22 14:22:40

Re: SpaceX Falcon 9R launch

#19 2014-04-22 16:26:09

Re: SpaceX Falcon 9R launch

#20 2014-04-22 16:45:13

Re: SpaceX Falcon 9R launch

#21 2014-04-22 18:07:28

Re: SpaceX Falcon 9R launch

#22 2014-04-22 18:44:12

Re: SpaceX Falcon 9R launch

#23 2014-04-22 19:48:47

Re: SpaceX Falcon 9R launch

#24 2014-04-22 20:45:00

Re: SpaceX Falcon 9R launch

#25 2014-04-22 21:41:54

Re: SpaceX Falcon 9R launch

Board footer