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SpaceX Falcon 9 Launches, Rocket Recovery Attempt Scrapped
An anonymous reader writes After scrubbing a launch Sunday because a radar glitch, and canceling one Tuesday due to high winds, SpaceX has successfully launched the Falcon 9 rocket holding the Deep Space Climate Observatory satellite. The DSCOVR will orbit between Earth and the sun, observing and providing advanced warning of particles and magnetic fields emitted by the sun. The planned attempt to recover the first stage of the Falcon 9 rocket via autonomous drone ship was scrapped due to huge waves in the Atlantic.
Landing on a barge is just a bit safer if something decides to go nuts.
More complicated, but if I lived in the neighbourhood of that Air Force launch pad, my insurance premiums might go up.
First-stage boosters normally just slam into the Atlantic and sink.
Now they bounce off a barge, explode, slam into the ocean and sink. Such an improvement.
Aside from avoiding cities and attorneys, landing on a barge in the ocean offers a couple of advantages:
The booster is already out over the ocean after launch from the coast. Redirecting it back to land would increase fuel needs and payload. (Musk says an increase of 15-30%).
The drone barge is able to move to the booster, an advantage difficult to mimic on land.
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And we will see landings once the method is perfected. We've already seen videos of past failed landings, simply not live. Sometimes this is because the video feed has to be retrieved manually from the hardware or because they simply don't wish to show an unpredictable video and damage their market worth. SpaceX might not be publicly traded, but they do have investors who might balk at such a public failure. Waiting to release the video with the right spin helps allay fears and lets SpaceX control the message, instead of letting the Internet write the headlines.
Earth-Sun L1 might be kinda hard to peer at, but SOHO is supposed to be parked there
Here is a list of published launches to Lagrange points
http://en.wikipedia.org/wiki/L...
Wherever You Go, There You Are
Landing on a barge is just a bit safer if something decides to go nuts.
More complicated, but if I lived in the neighbourhood of that Air Force launch pad, my insurance premiums might go up.
No more than if it were already an active launch pad, I'd guess.
Rockets have a self-destruct feature that is used if control is lost and the rocket strays near populated areas. It could be used on the way down just as well as on the way up.
If it weren't for deadlines, nothing would be late.
Anyone who watched the launch video...what is the purple water looking stuff that the camera switched to a couple times?
It is a shot from inside of the liquid oxygen tank AFAIK.
The liquid is a camera inside the second stage fuel tank, last launch they were showing it after the engine cut-off and you had large blobs of the stuff floating round inside. The black and white camera appears to be a thermal infra-red looking at the second stage engine nozzle.
But at all times you know where the rocket is, and can calculate where it might end up, based on various contingencies. If data shows that it might miss the landing point by 10 km, there's plenty of time to push the Big Red Button before it threatens anything on the ground.
If it weren't for deadlines, nothing would be late.
I think this demonstrates that the disadvantages likely outweigh the advantages, on average. If launches require optimal weather in two distant locations, it's going to be a lot harder to get rockets off the pad. Once stage recovery is working, I suspect it will be a lot cheaper to increase the fuel by 15-30% than to scrap a sizable fraction of launches.
Of course they don't necessarily have to pick one. They could default to using an ocean landing when weather in the atlantic is optimal (and thus load less fuel), or a land landing when weather in the atlantic is less ideal. Whether or not such a last-minute decision could realistic work is beyond my knowledge.
Basically, yeah. If you've got no gravity because you're not accelerating, you've got a rather interesting engineering problem if your objective is to drain a liquid from the "bottom" of a tank into a fuel pump when it comes time to light (or shut down and restart) a rocket engine. It's been a mostly-solved problem for decades, but the key word here is "mostly..."
I initially wondered "if the weathers so bad how did they ocean land it" then I stumbled across some of the ocean wave height maps. Apparently there is a LARGE area of ~20 ft seas off of most of the eastern sea board. You have to go a third of the way to Africa in order to get out of it. While I am sure that the rocket could get that far in no time at all I'd wager the barge is a bit slower.
http://www.wunderground.com/MA...
http://www.oceanweather.com/da...
Small solid fuel rockets to create acceleration before main engine ignition.
http://en.wikipedia.org/wiki/Ullage_motor
Waves in the ocean. That sure came out of left field. How could we have predicted that? We have the best experts money can buy making our plans, but how can we succeed when all this weird unpredictable stuff happens to us? /sarc
When the Air Force says, "You can land anywhere you want, except you can't land here, and you can't land here until you land somewhere else," you build a barge and take your chances with the waves.
Landing on a barge (or ASDS) would still be needed for deep space missions like DSCOVR which didn't have enough fuel left to boost back the stage towards launch pad. The center core of Falcon 9 Heavy wouldn't have enough fuel as well, and will most likely land on ASDS, while other two booster cores go back to landing pad.
SpaceX is in fact building a second ASDS which will be used for launches from Pacific coast.