SpaceX Launches Its First Functional Mission to the ISS

CommanderFrank

Cat Can't Scratch It
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The testing is over and SpaceX will begin a series of 12 scheduled missions to resupply the ISS with over 1k pounds of supplies per mission. The first mission commences on Sunday from Cape Canaveral at 11:35 PM EDT.

While other cargo capsules are stuffed with what amounts to space-station trash and released to burn up in the atmosphere, SpaceX craft will return to Earth with thousands of pounds of scientific samples and used hardware.
 
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Altogether, these 12 missions will bring more than 1,000 pounds of supplies to the ISS.

WTF? It carries less than 100lbs of cargo each trip? Not a very cheap method of delivering pizza.
 
WTF? It carries less than 100lbs of cargo each trip? Not a very cheap method of delivering pizza.

I'm betting a lot of the supplies simply take up too much room. A box of dehydrated food stuffs probably has food for months, but in of itself weighs next to nothing.
 
That's 1000 pounds of cargo per mission and returning with 1200 pounds of cargo on its trip back to Earth. That makes a bit more sense. :cool:
 
Looking at the specs it seems that it can handle up to 6000kg of cargo, so the fact they're only doing 1000 pounds at a shot sounds more like that's all the space station needs. Although does seem like a waste not to maximize the cargo.
 
Well I'm no expert but perhaps despite the maximum capacity, fuel efficiency might be something to factor in.
 
Probably a lighter cargo for an initial run, as not everything is certain at this point. Then they will ramp it up in further missions. :D
 
It's nice to see the private sector making a foot hold into space. It's a start.
 
Well I'm no expert but perhaps despite the maximum capacity, fuel efficiency might be something to factor in.
Probably not, I mean, the fuel doesn't cost much compared to the cost of a rocket. Maximum capacity would depend on how much fuel they can fit into their rocket.

And since they aren't able to recover the rocket part for reuse (although they're working on that), you'd want to load up as much as you can to get the most value out of it.

And there was a mention in the pre-flight press conference here: http://www.spacex.com/webcast/ about the cargo load being voluminous. Also that they had been contracted to bring up at least 20 tons over the next 12 missions, and that the way it looked, that it could be around 60 tons that they could lift. (Around 51:00 in the video, first question, video itself starts a bit around minute 37)
 
Well I'm no expert but perhaps despite the maximum capacity, fuel efficiency might be something to factor in.
Probably not much, the cargo is really insignificant to the weight of the fuel used to get it that high in the first place, plus the weight of the rocket.
 
It's nice to see the private sector making a foot hold into space. It's a start.

I'd bet money the next American launch to ISS with people will be in a crew rated Dragon. Sure, Boeing is building a capsule but it's fucking BOEING. It'll be ten years late and 400% over budget.
 
Probably a lighter cargo for an initial run, as not everything is certain at this point. Then they will ramp it up in further missions. :D

Maybe this? Anything goes wrong with a prototype plane during a shakedown, you can always parachute out. But out in space, what goes up, does not come down. You either drift in space and get left behind 'til the earth comes back next year, or you get vaporized in the atmosphere.

@sfsuphysics
1,000 pounds is less than 500kg. That would be about 40kg per trip. Makes me wonder how big the cargo hold is.

Currently, Dragon capsules are only approved for carrying cargo, but SpaceX is working with NASA to develop a human-safe Dragon craft for transporting ISS personnel to and from the station in the next few years.

So who's piloting it?
 
Looking at the specs it seems that it can handle up to 6000kg of cargo, so the fact they're only doing 1000 pounds at a shot sounds more like that's all the space station needs. Although does seem like a waste not to maximize the cargo.
Orbital distance will make a huge difference. Its probably designed to trade fuel for cargo capacity. The ISS isn't exactly in geo-sync but it has to be high enough it won't fall back anytime soon.
 
Great launch, went without issues. It should reach the ISS by Wednesday and return on Oct. 28th.

SpaceX is hoping to begin manned flights by 2015.
 
Orbital distance will make a huge difference. Its probably designed to trade fuel for cargo capacity. The ISS isn't exactly in geo-sync but it has to be high enough it won't fall back anytime soon.

230 miles, not exactly where the satellites roam :)
 
A engine failed on the first stage during flight, the first in-flight SpaceX engine failure. It was disclosed in the press conference. They didn't dodge a bullet, they took one and survived. First real test of the engine-out capability, some say would never work.

https://www.youtube.com/watch?v=y6zsZiVa998
 
They're unmanned capsules. That's what the successful test flight earlier this year was for -- to see if the capsule could dock to ISS by itself.

That must be where they got all that cargo capacity. Life support must weight a ton, literally.

Orbital distance will make a huge difference. Its probably designed to trade fuel for cargo capacity. The ISS isn't exactly in geo-sync but it has to be high enough it won't fall back anytime soon.

Not really a good argument to defend this case. That's basically saying 6,000 cargo capacity but neglecting to say that you'll have to drop 5,550 to achieve minimal use. To get 6,000 it won't even be able to leave the ground?
 
A engine failed on the first stage during flight, the first in-flight SpaceX engine failure. It was disclosed in the press conference. They didn't dodge a bullet, they took one and survived. First real test of the engine-out capability, some say would never work.

https://www.youtube.com/watch?v=y6zsZiVa998

It's great it still can keep going forward even with one destroyed engine.

From SpaceX's website:
Falcon 9 has nine Merlin engines clustered together. This vehicle will be capable of sustaining an engine failure at any point in flight and still successfully completing its mission. This actually results in an even higher level of reliability than a single engine stage. The SpaceX nine engine architecture is an improved version of the architecture employed by the Saturn V and Saturn I rockets of the Apollo Program, which had flawless flight records despite losing engines on a number of missions.
It's interesting that what was old is new again. The idea of using a reusable capsule to do resupply missions to the ISS, and later on capsule-module-lander for lunar missions, is being used again. It's as if we can't get away from these older designs. But, for what it's worth, the old saying holds true: "If it ain't broke, why fix it?" In the case of the Merlin rocket engines, it's an improvement of the old Saturn V five F-1 rockets and configuration. Nine Merlin engines with the ability to completely shutoff if neither one is not running properly prior to launch, and the ability to stay in flight with two engines out is a great feat of engineering.

I still believe that a true spaceflight and for future space exploration the best options would be an SSTO design or an in-orbit launch facility if we ever get that far. It's unfortunate that bad decisions and cost overruns killed VentureStar and the X-33 programs. At the very lest though, SpaceX is considering a reusable rocket launcher and lander starting with the "Grasshopper" that was tested recently. I still would love to see an SSTO designed spacecraft in my lifetime, something grander than the old Space Shuttle but can take off and land under its own power. We just lack the technology (and the money) to do it, and blocked by hardheaded stubborn political bureaucracy.

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As for the 6000 kg. maximum payload confusion, you have to realize that Dragon comes in two configurations and each configuration is composed of two parts. Actual payload capability is 3310 kg, split between these two parts-- a pressurized vessel and an unpressurized trunk. The other 2690 kg. of the payload comprises of the solar panels and telemetry systems, and the rest of the Dragon Spacecraft. It doesn't mean that Dragon can carry 6000 kg., what it means is that the payload mass is the entire Dragon Spacecraft itself-- all 6000 kg. And, that payload is what is carried on top of the two stage Falcon rocket.

The 3310 kg., as said before, is split between two parts. The first part is a pressurized capsule with a volume of 350 cu. ft. It is only the pressurized section that has a heatshield.

The unpressurized part which comprises the lower half of the Dragon spacecraft is 490 cu. ft. in the standard 7 ft. 7 in. trunk. It increases to 1200 cu. ft. in the 14 ft. trunk extension.

According to the press kit linked above, the total cargo is 1995 pounds (759 kg.) with packaging. That is well below the maximum COMBINED carrying capability of 3310 kg. I'm sure they could carry more but this is the first of 12 resupply missions to the ISS and I don't think NASA planned on maxing out the entire cargo in both the pressurized and unpressurized sections of the Dragon Spacecraft. In the press kit, they list what was being carried to the ISS. NASA most likely didn't plan for more items to be sent up there on the first mission. More items will probably be sent in subsequent missions with increasing cargo capacity. All of this, all 12 missions, is for both SpaceX and NASA to gauge the feasibility of Dragon to ferry items to and from the ISS, and to determine its reliability. If everything goes according to plan and all 12 missions are successful, SpaceX is planning on manned flights to the ISS in 2015, and returning crew back to Earth. Until that happens, we'll have to rely on Russia and their Soyuz capsules to launch and return astronauts to-and-from the ISS.

For now, the biggest success is that unmanned resupply missions have returned to US control. We no longer have to pay Russia and its space agency for it. That, and it's going to help (even if just a little) the economy here in the US-- maybe reinvigorating the space industry for the US economy. According to the CoTS program, a total of 20 ISS resupply missions are planned-- 12 from SpaceX and 8 from Orbital Sciences beginning in 2013.
 
I highly recommend watching the following videos from SpaceX:

"Plans for Full Reusability"
http://www.spacex.com/multimedia/videos.php?id=2&cat=recent

> Their plan on a reusable, non-parachute rocket and propulsive lander system for both manned and unmanned flights. Future variations will probably be used for landing on the moon or Mars.

First test of the "Grasshopper" as showcased in the above CG video
http://www.youtube.com/watch?v=pzXlUw2WhcE

> Similar designs are being tested by NASA called Morpheus using methane as the propellant and one other that I forgot the name now.
 
Not really a good argument to defend this case. That's basically saying 6,000 cargo capacity but neglecting to say that you'll have to drop 5,550 to achieve minimal use. To get 6,000 it won't even be able to leave the ground?
Although the detailed explanation above is probably the reason, I don't understand your comment. There are different levels of orbit you can achieve and the fuel required as a function of payload is equally different. Launching something so it orbits a few dozen times and falls back is a lot less fuel than if I want it to last a couple of decades which is a lot less fuel than if I want to achieve geosynchronous orbit. So by trading cargo space for fuel space you can maximize different payloads for different levels of orbit.

Seems strange this system is a fixed fuel / fixed cargo system. Means its optimized for a single purpose.
 
Although the detailed explanation above is probably the reason, I don't understand your comment. There are different levels of orbit you can achieve and the fuel required as a function of payload is equally different. Launching something so it orbits a few dozen times and falls back is a lot less fuel than if I want it to last a couple of decades which is a lot less fuel than if I want to achieve geosynchronous orbit. So by trading cargo space for fuel space you can maximize different payloads for different levels of orbit.

Seems strange this system is a fixed fuel / fixed cargo system. Means its optimized for a single purpose.

octoberasian already did a good explanation, the 6000 pounds is the entire ship as 'cargo' for the launch rocket.

However, if we were to go to your original comment, your claim that they already have to trade fuel for cargo just for this doesn't really make it practical. 6000 pounds, and your justifying that it must be fuel being traded for cargo means 5,550 goes to fuel? Just for this? If you were hiring a van and they say it can carry 1,000 pounds of cargo, do you expect 900 pounds to be fuel? True, there are different orbits, but the ISS is probably one of the *LOWEST* ones, it's only 250miles, a typical satellite is a lot further than that. If what you say is true, and you need 5,550kg of fuel just for a basic mission, then the proper rating for the SpaceX should only be 50kg. Anything more than that is just false advertising from a product marketing department.
 
octoberasian already did a good explanation, the 6000 pounds is the entire ship as 'cargo' for the launch rocket.

However, if we were to go to your original comment, your claim that they already have to trade fuel for cargo just for this doesn't really make it practical. 6000 pounds, and your justifying that it must be fuel being traded for cargo means 5,550 goes to fuel? Just for this? If you were hiring a van and they say it can carry 1,000 pounds of cargo, do you expect 900 pounds to be fuel? True, there are different orbits, but the ISS is probably one of the *LOWEST* ones, it's only 250miles, a typical satellite is a lot further than that. If what you say is true, and you need 5,550kg of fuel just for a basic mission, then the proper rating for the SpaceX should only be 50kg. Anything more than that is just false advertising from a product marketing department.
When I said trade fuel for cargo, I wasn't talking about all the fuel. And I was giving a theory to a possible explanation for the conflicting specs. I wouldn't call it false advertising if when asked for details they would be more forthcoming. Like when a car advertises fuel economy and horsepower. You usually don't get that listed fuel economy when you are running at the max horsepower point.
 
Although the detailed explanation above is probably the reason, I don't understand your comment. There are different levels of orbit you can achieve and the fuel required as a function of payload is equally different. Launching something so it orbits a few dozen times and falls back is a lot less fuel than if I want it to last a couple of decades which is a lot less fuel than if I want to achieve geosynchronous orbit. So by trading cargo space for fuel space you can maximize different payloads for different levels of orbit.

Seems strange this system is a fixed fuel / fixed cargo system. Means its optimized for a single purpose.

That pretty much sums it up.

It is, like the older Soyuz capsule and rocket engines, a fixed fuel/fixed cargo system.

The difference between the two is engine design, size and cargo capacity. The Dragon spacecraft is indeed optimized to do one thing and one thing only, for now, and that is to ferry supplies to-and-from the ISS. A future Dragon spacecraft will be able to carry up to 7 astronauts to the ISS and return them to Earth planned sometime in 2015. Both stages of the Falcon 9 rocket is also fixed in size and fuel capacity, like with the Soyuz rockets. In fact, I would say the Falcon 9 is a better and more efficient design than the Soyuz rockets. Unlike with Soyuz spacecraft that has more than three configurations, there are currently only two configurations for cargo and one for manned flights.

For larger payloads such as, for example, space station parts for an orbital launch platform, the Falcon Heavy would be used. That rocket, when completed, would have the ability to carry up to 53000 kg. into LEO (low earth orbit). However, it is still a fixed design/fixed fuel system like Soyuz.

It's like what I said above that it's interesting that for the majority of the commercial reusable vehicles being constructed, contemplated and those by NASA and its contractors as well, is a return to a fixed platform. And, I would not be surprised it's because of costs alone. The Space Shuttle was $1.5 billion per launch approximately, which is considerably more than what it costs to use Falcon 9-- between $49 to $54 million (not including miscellaneous costs, dependent on cargo capacity and whether it is LEO or GTO).

In regards to fuel capacity, lift, and cargo/payload, there is a saying I read before when I learned about rockets and spacecraft in the past several years: "You carry as much fuel that is needed to carry yourself into space." In other words, with the Falcon 9 you carry as much fuel that is needed to carry a 6000 kg. (not pounds) payload-- Dragon-- plus your fuel for the rockets to get that payload into space. There is a lot of math involved in this, and believe me there is, and that is all taken into consideration in the overall design of the rocket. You need enough thrust to overcome Earth's gravity, and enough fuel to sustain that thrust and acceleration until you reach LEO or any other Earth orbits. These same issues were contemplated over and over again during the design of the Saturn V rockets back in the early 1960s. With a maximum payload capacity of 120,000 kg. (260,000 lbs.), it needed two rocket stages to lift both the third stage rocket, the lunar lander and the Apollo command/service module plus fuel to get it out of the Earth's atmosphere.

These same considerations are used fifty years later in the Falcon rockets as well. The one we saw launched last night is using "version 1.0" of the stage one rocket giving it a capability of carrying a total maximum payload of around 9000 kg. (6000 kg. belonging to Dragon's maximum payload) to LEO. So, that means that there is around a FIXED AMOUNT of 3000 kg. (~19840 lbs.) of fuel for both the stage one and two rockets in version 1.0. Falcon version 1.1 planned for 2013 will use a the more powerful Merlin 1D engines, which brings maximum payload capacity to 13150 kg. to LEO, and 4850 kg. to GTO (geostationary orbit), but an increased amount of fuel (greater than 3000 kg.). Always remember that payload is the overall carrying capacity of the rocket-- fuel and cargo. So, Falcon 9 v1.1 will be carrying 13150 kg. that includes the Dragon spacecraft and its fuel. That's all payload.

Now, remember what I said above: "You carry as much fuel that is needed to carry yourself into space." From surface to LEO with a maximum payload of 13150 kg. to carry into LEO, you carry the necessary amount of fuel to do that. And, that is in fixed amounts in both the first and second stage rockets. It's always full and the fuel tanks are topped off prior to launch to ensure that the final payload-- Dragon-- reaches LEO. Now, to go higher such as GTO, you will need greater amounts of fuel and, as a result, maximum cargo capacity decreases as a result because of the added weight. Similar issues were presented to the Apollo program and the first Lunar Rover. With the possibility of increasing mass of the payloads, a fifth F-1 rocket was added to the first stage rocket as a result. For the Falcon 9 rocket, to reach a higher orbit such as GTO, you have to compromise on one of three things:
  1. Decrease the payload you're carrying.
  2. Add more rockets (as in the Saturn V stage one rocket).
  3. Increase the size of the fuel tanks.
Of course, that's not taking into consideration the physics and math involved to recalculate the amount of thrust needed to carry the extra fuel or extra cargo. For GTO, the compromise was made in carrying capacity-- drop the maximum payload. In other words, Falcon's (v1.1) overall payload capacity is decreased from 13150 kg. to 4850 kg. That means compromises were made in how much cargo it can carry. The v1.1 Falcon rocket will be more powerful, which means more fuel used and therefore more fuel needs to be carried on the rocket. To LEO, it has enough fuel to lift 13150 kg. (fuel + Dragon) into orbit. To GTO, the same amount of fuel can only lift 4850 kg. (fuel + Dragon) into orbit. That is because the Falcon 9 is a fixed design and only has just a specific maximum amount of fuel to carry itself and its cargo into LEO or GTO. To carry the same amount of payload to GTO as it does to LEO-- 13150 kg.-- Falcon 9 would need extra rocket engines; more rocket stages; or more extra fuel; or larger and more powerful rockets and extra fuel. That makes the design more costly, larger and heavier in the end.

Therefore, that's why SpaceX is planning on launching the Falcon Heavy sometime next year for heavier payloads to LEO or lighter payloads into GTO. The same rocket is also going to carry SpaceX's proposed Red Dragon spacecraft to Mars.

These same issues present themselves in SSTO (single stage-to-orbit) spacecraft designs as well. An SSTO spacecraft needs a powerful enough engine (or engines) and all the fuel necessary to carry the entire spacecraft plus its cargo and weight of the fuel into orbit, while still keeping its weight small enough to not complicate the overall design of the spacecraft. VentureStar and X-33 are good examples of an SSTO design, but failed in the end because of the fuel tank's weight and design (plus other external issues). Space Shuttle, even though it isn't an SSTO spacecraft, needed two solid rocket boosters and an external fuel tank to achieve LEO. To convert it into an SSTO craft means housing all that rocket fuel and engines in a single spacecraft. Hence, expensive design overall, and thus part of the reasons the Shuttle was retired.

Until an efficient and affordable SSTO spacecraft can be made, Dragon and its competitors are meant to be both cheap and reusable. The rockets themselves will possibly be reusable in the near future.

Here's a TL;DR version: http://kerbalspaceprogram.com/

I suggest playing that game. It'll teach you a lot about rocket design in a rather simple way since it's pretty much close to reality and uses real physics.

Another TL;DR version is, again: "You carry as much fuel that is needed to carry yourself into space."

In other words, the heavier your cargo is, you need more powerful rockets; or more fuel for the same lesser powerful rockets; or add more rocket engines to the same rocket. Or, just simply decrease the maximum payload capacity in exchange for higher orbits.
 
What I'm mainly interested in is what did it cost TAXPAYERS to send the shuttle up for a resupply mission and how much does this private corporation do it for.
I'm betting there is a staggering cost savings.
Like in any sci-fy tales; monolithic corporation control space.
In our case the Gub-ment is too busy writing check to pay babies-mamma. Nothing left for space exploration.

Sign me up for space mining. :)
 
Ooh dear. This is starting to worry a few people. No update anywhere on the GNC door (located under the side hatch) is successfully deployed. Without this, there is no mission because the station's arm can't capture Dragon for docking/birthing.
 
Not looking good with the secondary payload. The Orbcomm sat is in a useless orbit right now. An effort might be underway, to change the orbital parameters, to improve the short life. The first stage engine failure must have eaten into the second stage propellent margins.
 
I'm betting a lot of the supplies simply take up too much room. A box of dehydrated food stuffs probably has food for months, but in of itself weighs next to nothing.
Luckily they parked the ISS next to a river, so there is no need for water on the space station.
 
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