Brotoro Posted November 23, 2014 Share Posted November 23, 2014 This is going to be cool. Link to comment Share on other sites More sharing options...
StrandedonEarth Posted November 23, 2014 Share Posted November 23, 2014 I can't wait. It'll be something historical if he pulls it off. The procedure once it's down would be interesting. Link to comment Share on other sites More sharing options...
Motokid600 Posted November 23, 2014 Share Posted November 23, 2014 Are they actually putting a payload into orbit or is his solely just a demonstration? Because I can't imagine SpaceX waiting on good sea conditions. Because they practicality never are... The sea is rough 90% of the time so are they really going to wait for calm seas before the launch? If so that Dec16 date has a good chance of being delayed... Link to comment Share on other sites More sharing options...
B787_300 Posted November 23, 2014 Share Posted November 23, 2014 Granted the barge is unmanned or at least minimally manned, so more than likely there will be a boat close by that will have a crew on that will board the barge and tie down the rocket in some fashion for transport to shore. Link to comment Share on other sites More sharing options...
How2FoldSoup Posted November 23, 2014 Share Posted November 23, 2014 Are they actually putting a payload into orbit or is his solely just a demonstration? Because I can't imagine SpaceX waiting on good sea conditions. Because they practicality never are... The sea is rough 90% of the time so are they really going to wait for calm seas before the launch? If so that Dec16 date has a good chance of being delayed...The barge is equipped with stabilizing thrusters to keep it in place with an error of only 3 meters. It's designed from the same technology drilling barges and oil platforms use to keep in place. It'll be rough, but it's a pretty big barge and it will definitely keep stay where it needs to be. How flat it will be depends on just how bad the weather is on the launch day. They are launching CRS-5 if I remember correctly which is the 5th resupply mission to the ISS. Link to comment Share on other sites More sharing options...
B787_300 Posted November 23, 2014 Share Posted November 23, 2014 Also the barge has been confirmed to have some sort of wave damping system on it, which i bet can decrease the apparent wave height by ~2m Link to comment Share on other sites More sharing options...
How2FoldSoup Posted November 23, 2014 Share Posted November 23, 2014 Also the barge has been confirmed to have some sort of wave damping system on it, which i bet can decrease the apparent wave height by ~2mI didn't think about it but that seems about right. Oil rig transfer boats(I think it was these) and other yachts have pretty cool systems that dampen waves. I forget exactly how it works, it's been awhile since I've read about it, but they can make 5foot swells seem like perfectly calm. It's pretty amazing. It works by moving ballast around I think, I could be completely wrong though. Link to comment Share on other sites More sharing options...
Motokid600 Posted November 23, 2014 Share Posted November 23, 2014 2m? Wow.. I suppose the hope then is for no excessively rough seas. I hope we get good footage. It'll be quite the sight. Link to comment Share on other sites More sharing options...
RocketPilot573 Posted November 23, 2014 Share Posted November 23, 2014 Now THIS should be interesting. I hope they will have an aircraft around or a boat that can take HD video of the descent. Link to comment Share on other sites More sharing options...
Airlock Posted November 23, 2014 Share Posted November 23, 2014 From Elon: https://twitter.com/elonmusk/status/536263260056850432"Base is 300 ft by 100 ft, with wings that extend width to 170 ft. Will allow refuel & rocket flyback in future."They want to launch from the barge??? Link to comment Share on other sites More sharing options...
Rakaydos Posted November 23, 2014 Share Posted November 23, 2014 From Elon: https://twitter.com/elonmusk/status/536263260056850432"Base is 300 ft by 100 ft, with wings that extend width to 170 ft. Will allow refuel & rocket flyback in future."They want to launch from the barge???Not the WHOLE rocket... just the flyback stage. They land it, put 5 bucks in the tank, and it flys back to the launchpad Link to comment Share on other sites More sharing options...
PakledHostage Posted November 23, 2014 Share Posted November 23, 2014 Also the barge has been confirmed to have some sort of wave damping system on it, which i bet can decrease the apparent wave height by ~2mI can't think of a way to "reduce the apparent wave height" without pumping water ballast back and forth in floating pontoons to increase/decrease their buoyancy as the waves pass. SpaceX's barge appears to have only one hull so this wouldnt be an option. At best, they could stabilize how much the barge rolls and pitches due to the waves while floating up and down in them and holding position to within 3 metres.The amount of up/down motion would then depend on the wave length (i.e. short wavelength waves that are freshly being churned up or are running against a current vs. long rollers left over from a distant storm.)As for conditions at sea, you can view them online on NOAA's marine forecast web page. The forecasts and current conditions are updated a couple of times a day. I've posted an example below. Florida is in the lower left, the UK is in the upper right. Contours are the mean significant wave height in metres. Mean significant wave height is the average of the largest third of waves. That means that ~83% of waves are smaller than the given height while ~17% are bigger. Link to comment Share on other sites More sharing options...
Motokid600 Posted November 23, 2014 Share Posted November 23, 2014 Not the WHOLE rocket... just the flyback stage. They land it, put 5 bucks in the tank, and it flys back to the launchpadStill though that's incredible. Is that really cheaper then just tugging the barge back to shore? Itd be quicker that's for sure... And time is money I suppose. Link to comment Share on other sites More sharing options...
B787_300 Posted November 23, 2014 Share Posted November 23, 2014 PakledHostage you can dampen out the motion by using vertical motors, hydraulically lifting and lowering the deck, having extendable fins like on cruise ships, partially submerging the hull to reduce the freeboard, etc. There are a bunch of differernt ways all with their own drawbacks Link to comment Share on other sites More sharing options...
magnemoe Posted November 24, 2014 Share Posted November 24, 2014 Still though that's incredible. Is that really cheaper then just tugging the barge back to shore? Itd be quicker that's for sure... And time is money I suppose.Main problem with an relaunch is reliability and chance of fail during the return flight, it would not cost much outside that. Problem with towing the barge is that you expose the rocket of sea spray.I thought that flyback would be interesting for Russia as they fly over land, you can have an small base for the rocket to land, here you could do an better inspection than on the barge, rocket would also be to large to transport cheaply on roads. Link to comment Share on other sites More sharing options...
PakledHostage Posted November 24, 2014 Share Posted November 24, 2014 you can dampen out the motion by using vertical motors, hydraulically lifting and lowering the deck, having extendable fins like on cruise ships, partially submerging the hull to reduce the freeboard, etc. Right, but I really doubt vanes are used or are even practical in this case. The vanes on cruise ships work because the ship moves through the water. They work like wings to apply a righting force that ramps out roll. The SpaceX platform is stationary. The deck may have hydraulic actuators to lift and lower it (that's a good thought BTW), but it isn't clear from the limited info we have that it has that capability.My point stands. You can relatively "easily" damp out pitch and roll oscillations, but vertical motion is much harder on a monohulled barge. Link to comment Share on other sites More sharing options...
Airlock Posted November 24, 2014 Share Posted November 24, 2014 Not the WHOLE rocket... just the flyback stage. They land it, put 5 bucks in the tank, and it flys back to the launchpadOh, no no no, I understand that (although I can envision a sea-launch architecture for future BFR/MCT flights).I'm just concerned flying first stages back from the barge will cut down on the number of times they can be reused. Link to comment Share on other sites More sharing options...
Brotoro Posted November 24, 2014 Share Posted November 24, 2014 They really want to land on barges as a long-term solution? I thought they were only going to do this until they convinced the powers-that-be that they are able to reliably plop the stage down onto a chosen landing spot. In which case I wouldn't think it would even matter (for that purpose) if the stage fell over later due to the shifting deck. Link to comment Share on other sites More sharing options...
Airlock Posted November 24, 2014 Share Posted November 24, 2014 They really want to land on barges as a long-term solution? I thought they were only going to do this until they convinced the powers-that-be that they are able to reliably plop the stage down onto a chosen landing spot. In which case I wouldn't think it would even matter (for that purpose) if the stage fell over later due to the shifting deck.I assume they're still planning to RTLS eventually. However, landing on a platform at sea may allow for larger payloads on the F9, as well as FH central core recovery. Link to comment Share on other sites More sharing options...
Rakaydos Posted November 24, 2014 Share Posted November 24, 2014 I think it's more a matter of "The goverment is making us use a barge at the beginning... what can we use a barge for later on?" and building the barge from the outset for still hypothetical advanced missions. Link to comment Share on other sites More sharing options...
DaveofDefeat Posted November 24, 2014 Share Posted November 24, 2014 If this was going to be for anything but the short term, wouldn't it make more sense to build a semi submersible? Link to comment Share on other sites More sharing options...
Aethon Posted November 26, 2014 Author Share Posted November 26, 2014 Sunny day. Keepin' the, clouds away. On my way, to where there is, no, air!Got your ticket? Eight days 'till go time.http://www.nasa.gov/content/sesame-street-characters-on-board-with-orion/index.html#.VHYClTHF-Yd Link to comment Share on other sites More sharing options...
Voyager55 Posted November 26, 2014 Share Posted November 26, 2014 I always assumed the Orion was meant to be docked with transit modules, such as a centrifuge or a torpor compartment. Link to comment Share on other sites More sharing options...
Nibb31 Posted November 26, 2014 Share Posted November 26, 2014 I always assumed the Orion was meant to be docked with transit modules, such as a centrifuge or a torpor compartment.No idea where you picked that up from. NASA isn't building any transit modules because Congress isn't funding any expedition missions. And centrifuges and "torpor" modules belong in science fiction. Link to comment Share on other sites More sharing options...
Bill Phil Posted November 27, 2014 Share Posted November 27, 2014 Orion hasn't been just a constellation in a while, remember NPP Orion, back in the 1960s? Hmm, if they had an Orion NPP as a payload... Now THAT would be interesting! Link to comment Share on other sites More sharing options...
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