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SpaceX Lands Falcon 9 Rocket At Cape Canaveral (planetary.org)
Rei writes: At 8:40 PM today, SpaceX successfully launched and relanded the first stage of its Falcon 9 rocket at Cape Canaveral, as well as delivering to orbit the last portion of ORBCOMM's communication satellite constellation. This also marks SpaceX's return to flight and the first launch of the "Full Thrust" Falcon 9 v1.1 with densified (extremely chilled) propellants. The company will now shift its efforts toward catching up on its backlog, investigating and refurbishing its landed first stage, and preparing for the maiden flight of the Falcon Heavy rocket this spring. Congratulations to everyone at SpaceX!
Here is a great post from Elon with background on tonight's launch: http://www.spacex.com/news/201...
Look, I just made you read my signature.
No one knows, this booster will probably be dissected to see just where the wear/tear occurs. After that, SpaceX will probably have to mod/update future boosters to ensure it can fly multiple times. It may be that the cost to mod/upgrade/refurbish will be more expensive than just rebuilding, but we'll have to see.
That said I don't think the barge was ever the target landing location. I think the barge was necessary to get regulatory approval to come in over the land. Prove you can hit your target first where you won't hurt / destroy anything then you can try it here.
I read some comments by Elon from earlier today that mentioned the F9 could get the payload/2nd stage to 100km and 5000m/s and land back at the launch site, OR to 100km and 8000m/s and land on a sea platform. So it sounds like the barge/platform might still be in the cards at some point.
Yeah, but the New Shepherd was launched essentially straight up and came straight back down, all in the middle of the desert. Falcon 9, going orbital and coming back near population, had significantly higher range safety considerations.
No one knows, this booster will probably be dissected to see just where the wear/tear occurs. After that, SpaceX will probably have to mod/update future boosters to ensure it can fly multiple times. It may be that the cost to mod/upgrade/refurbish will be more expensive than just rebuilding, but we'll have to see.
Actually I think SpaceX got a pretty good idea, they've tested burn/reignite cycles staticly and found the engines can be reused 40 times, since that's likely to be the most expensive component that'll probably be their target. And if the reliability stays high there's a good chance that 1 in 40 launches will require a full burn, no reuse booster so there's no waste. They've said the first stage is roughly 70% of the cost and just refueling the rocket costs about 0.3% of a full launch, so the cost savings potential is huge.
Live today, because you never know what tomorrow brings
How many times can they reuse the rocket?
I read that the engines are being designed for about 10-20 flights before performing major overhauls of the engines. That means the intention is to literally take the lower stage core, bring it directly to the integration building like it came fresh from the factory, and put it together with another rocket several times in a row with only a cursory inspection of the engines themselves.... at about the level that jet engines get between flights at a typical major airport for an airliner.
At about 10 flights, they plan on performing a major tear-down and overhaul of the engines, but I don't know how many flights they think can be pushed out of them. I would guess they are hoping at least for about 30-50 flights before the engines are simply retired. It is a far cry from the RS-25 (aka the SSME for the Shuttle program) that had to be rebuilt completely after each flight.
In the meantime, SpaceX plans on sending the rocket to New Mexico for some extensive testing where the engines are going to be pushed to see if the anticipated engineering limits are going to hold true to actual engine performance where the rocket is going to be flown into space (aka above 100 km) as a part of those tests. Mostly straight up and down testing though and not with the intention to put something into orbit. The launch pad in New Mexico has already been built, but SpaceX didn't want to build another test vehicle when they figured they would simply get one of the recovered cores to perform the testing.
I guess SpaceX got their test platform today :)
Insurance is 10%, paid by the payload owner. Fuel is 0.3%. 70% is the 1st stage.
This is huge.
Just to be clear, the Falcon 9 first stage went nowhere close to going orbital - altitude accounts for only about 5% of the energy difference between orbit and the Earth's surface, the rest is kinetic energy, or speed. And Stage 1 only got up to what, 5800km/h? That's only 1.6km/s. Meanwhile Low Earth Orbit velocity is 7.8km/s. Stage 1 barely reached 20% of the necessary speed, which translates to barely 4% of the necessary kinetic energy. It's job is mostly just to get above the efficiency-robbing atmosphere and give Stage 2 as much of a boost as its fuel budget allows. Most of its energy is wasted fighting aerodynamic drag and providing a support force against gravity. It's Stage 2 that can really pour on the speed, and it did, reaching 7.22m/s at an altitude of 630km (orbital speed falls with increasing altitude)
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It appears you've never landed an aircraft. You did mention ome of three major challenges, though.
> The reason that a carrier landing is harder
There are at least three reasons that a carrier landing is harder .
1. The runway has been relocated, so you have no approach landmarks. The first thing is that you actually start lining up for landing many miles from where you intend to touch down. To land in Baltimore, you might learn that you need take a right at Atlantic City, NJ. With a carrier, your turns and altitude changes are never in the same place. This one doesn't apply so much to the rocket.
2. Wave motion (AGL keeps moving). The magic to a smooth landing is to make it so that you reach EXACTLY zero altitude at precisely the same moment when your forward motion puts you at the beginning of the runway, at the same instant that your lateral adjustment, with wind, puts you in the middle of the runway, while at the same instant you have ceased lateral motion against the wind and brought the yaw exactly parallel to the runway, at the same time roll goes to zero, while maintaining proper flare (pitch). In other words, the craft is moving in six dimensions* and you try to hit just the right mark in all six dimensions at precisely the same time. It's awfully tough to hit zero AGL at exactly the right time when the ground is moving up towards you, then down away from you. Too difficult for me to try in real life. SpaceX has had much trouble with this. They had the rocket perfectly vertical, and they were able to reach 0 AGL, but they couldn't do both at the same time - touch down while the vehicle was vertical. It's much easier to do that of zero AGL remains constant, rather than having the ocean move the barge up and down.
3. The landing area is much smaller. Factors 1 and 2 can easily cause the landing to occur 40 feet to far to the right, or 400 feet to far down the runway. An ocean-going landing area isn't big enough to allow any margin of error.
> The reason that a carrier landing is harder is because the runway is shorter. With a vertical landing vehicle, it's a non-issue.
The best way to really understand this is to try landing a model helicopter smoothly. Not a drone that flies itself when you let go of the stick, but an old-fashioned model heli. If you can't try that, imagine a perfect, frictionless air-hockey table - the puck glides absolutely perfectly across the table. The lightest feather touch will send it to the other side of the table because there is no friction. That's hover - there is no friction keeping you in the same spot over the ground. Your job is to position the puck at an exact spot on the table and keep in there by tossing pebbles at it.
I think this is much more relevant actually: https://youtu.be/O5bTbVbe4e4?t...
The US already has a reliable launch vehicle called the X37-B. It can reach orbit (...) The US is also developing the Space Launch System (SLS). (...) Why waste money and resources on rockets whose sole purpose is to launch satellites into orbit or play taxi for the ISS?
Not sure if troll or serious, but since your posting history looks rather sincere... The X37-B is not a launch vehicle, it launches on top of an Atlas rocket. As for the SLS program it will cost $20-35 billion to fully develop and hideously expensive to launch, just throwing away four RD-25 engines will cost around $900 million alone. Given the extremely few launches that are planned, estimates for the amortized cost has been as high as $5 billion/launch. When you compare that to SpaceX's fixed $60-130 million per launch that also covers their R&D expenses it's a bargain.
When the Falcon Heavy launches you get 70% of a SLS Block 1 for a small fraction of the cost and you can assemble 50+ ton modules in LEO if you need to. Like you could launch the whole Apollo mission (CSM+LEM) in one go, then add engines, then add fuel and break orbit for TLI. Looking at delta-v charts there doesn't seem to be any significant penalty for doing so and docking in space we've done many, many times now with the ISS. The only downside is if you genuinely need an even larger monolithic module due to structural integrity or something.
Live today, because you never know what tomorrow brings
Here's what I don't understand. I think stage 1 landed about 10 miles from where it launched. It was travelling almost exactly 6,000 kph at separation. Did it really slow down to zero and actually fly back the way it came to land at the Cape? I guess it takes much, much less fuel to go from 6,000 to zero on an empty first stage in vacuum versus 0 to 6k, fully loaded in the atmosphere.
No, it didn't stop and turn around as such, the primary direction is up and it just reversed the slight horizontal component and slowed itself down as it fell to earth. This infographic is pretty good, it's not at all like a plane turning around.
Live today, because you never know what tomorrow brings