Kryten Posted June 19, 2016 Share Posted June 19, 2016 3 minutes ago, LordFerret said: That capsule landing looked pretty hard. Retrorockets kick up a lot of dust, you see the same on Soyuz landings. Makes it look harder than it is. 14 minutes ago, YNM said: 2nd EDIT : really, capsules rocks that "hard" during parachuting ? Only happened because they were down one drogue as part of the test. Link to comment Share on other sites More sharing options...
Streetwind Posted June 19, 2016 Share Posted June 19, 2016 4 minutes ago, LordFerret said: That capsule landing looked pretty hard. The retrorockets kick up a lot of dust in the desert, but the actual touchdown is pretty gentle. Something like 2 mph, the casters said. Link to comment Share on other sites More sharing options...
PB666 Posted June 19, 2016 Share Posted June 19, 2016 (edited) 1 hour ago, Hysterrics said: http://spacex.yasiu.pl/ Looks like the frame eventually crumpled and much fell overboard or was push over board? If what i am seeing is correct , what a mess. Edited June 19, 2016 by PB666 Link to comment Share on other sites More sharing options...
wumpus Posted June 19, 2016 Share Posted June 19, 2016 On 6/17/2016 at 0:24 PM, Motokid600 said: I've been trying to wrap my head around this. Last night during EJ's stream a Space X employee stated that Falcon saw the low thrust on one of the radial engines and shut them both down early to prevent offset thrust forcing the center engine to do the rest of the work and due to gravity loses ran out of fuel a few feet above the ground. What I can't figure out is how that made for a hover. I would think two engines shutting down early would prevent Falcon from slowing down at all and crashing on the deck. A big red flag is that falcon 9 shouldn't be *able* to hover. If it actually hovered, that meant that an engine was throttled way out of spec (more likely it wasn't see below). To hover above the pad like that takes a bunch of failures: braking too hard with the three engines to stop the booster too high, followed by a single engine suddenly trying to throttle "too hard" (while merlins can restart, I'm reasonably sure they can't stop and restart with the millisecond timing required to land once the rocket stopped 10-20 m off the deck). I'm also pretty sure that it didn't "hover". What I suspect is what we are seeing and our eyes insist that it is "hovering" because they assume that anything "hovering" isn't 10 stories tall and falling at 9.8m/s**2). It came to a stop (or near stop, to the point that the TWR of a single merlin wouldn't let it land), and then a landing just wasn't going to happen. Link to comment Share on other sites More sharing options...
Robotengineer Posted June 19, 2016 Share Posted June 19, 2016 Shame on Blue Origin for using imperial units. Real rocket webcasts use metric. Link to comment Share on other sites More sharing options...
LordFerret Posted June 19, 2016 Share Posted June 19, 2016 1 hour ago, Kryten said: Retrorockets kick up a lot of dust, you see the same on Soyuz landings. Makes it look harder than it is. 1 hour ago, Streetwind said: The retrorockets kick up a lot of dust in the desert, but the actual touchdown is pretty gentle. Something like 2 mph, the casters said. Yes, I know that. I also heard the announcer's comment. I was watching the speed indicator (on the right side of the screen), expecting to see a sharp decrease in speed, but I didn't, hence my impression. They commented about a brief 5g pull, but that didn't have anything to do with the retros firing... so of course I'm wondering how many g's are pulled during retro firing. Any idea? Link to comment Share on other sites More sharing options...
Kryten Posted June 19, 2016 Share Posted June 19, 2016 If you look back the speed indicator had a lot of lag on it, I wouldn't read too much into the readings it gave, Link to comment Share on other sites More sharing options...
PB666 Posted June 19, 2016 Share Posted June 19, 2016 12 minutes ago, wumpus said: A big red flag is that falcon 9 shouldn't be *able* to hover. If it actually hovered, that meant that an engine was throttled way out of spec (more likely it wasn't see below). To hover above the pad like that takes a bunch of failures: braking too hard with the three engines to stop the booster too high, followed by a single engine suddenly trying to throttle "too hard" (while merlins can restart, I'm reasonably sure they can't stop and restart with the millisecond timing required to land once the rocket stopped 10-20 m off the deck). I'm also pretty sure that it didn't "hover". What I suspect is what we are seeing and our eyes insist that it is "hovering" because they assume that anything "hovering" isn't 10 stories tall and falling at 9.8m/s**2). It came to a stop (or near stop, to the point that the TWR of a single merlin wouldn't let it land), and then a landing just wasn't going to happen. You make the assumption that any engine had sufficent oxygen, they might have all been starving when it hit the deck. There is a dception because of the hieght of the rocket and distance. But its not efficient for a rocket to decellerate an then slow the deceleration so far above the ground, the wave heght on a bad day is about 3 meters, ive been oout in squals with 5m waves, if you add another meter variance per tides it means that they where about 10 to 50 meters two high before the switched deceleration modes. Lets say they were 10 meters too high when their engines began failing, and that they were are say 2 meters per second with only 0.75g*m, d = v0t + 0.5at^2 that gives an impact in about 2.2 seconds traveling at 7.5 meters per second. Link to comment Share on other sites More sharing options...
PB666 Posted June 19, 2016 Share Posted June 19, 2016 17 minutes ago, Robotengineer said: Shame on Blue Origin for using imperial units. Real rocket webcasts use metric. Yeah those data reporting units may or may not catch the deceleration. For the SX telemetry i caught periods up to about a quarter second where the feed had basically stopped. Link to comment Share on other sites More sharing options...
wumpus Posted June 19, 2016 Share Posted June 19, 2016 1 minute ago, PB666 said: You make the assumption that any engine had sufficent oxygen, they might have all been starving when it hit the deck. Unless things have drastically changed, they only land on a single engine. Had they failed to shut two down due to starvation (and insufficient thrust), that may have been the reason that three starving engines were still firing. After a string of soft landings, it looks like they have wave issues mostly under control (everyone involved in Navy aviation is laughing at me, but boosters are more expendable then Navy aircraft & flight crews). Still, this one looks like it was doomed in the air, even if the Sea is certain to take its share of boosters. Link to comment Share on other sites More sharing options...
PB666 Posted June 19, 2016 Share Posted June 19, 2016 1 hour ago, wumpus said: Unless things have drastically changed, they only land on a single engine. Had they failed to shut two down due to starvation (and insufficient thrust), that may have been the reason that three starving engines were still firing. After a string of soft landings, it looks like they have wave issues mostly under control (everyone involved in Navy aviation is laughing at me, but boosters are more expendable then Navy aircraft & flight crews). Still, this one looks like it was doomed in the air, even if the Sea is certain to take its share of boosters. No boosters, jet engines and afterburners. The keep a stock of retired aircraft which they ca borrow parts from. Link to comment Share on other sites More sharing options...
softweir Posted June 19, 2016 Share Posted June 19, 2016 1 hour ago, PB666 said: No boosters, jet engines and afterburners. The keep a stock of retired aircraft which they ca borrow parts from. He was back to talking about SpaceX when he said boosters. That's a bad habit, having multi-topic sentences! It leads to confusion. Link to comment Share on other sites More sharing options...
Mitchz95 Posted June 19, 2016 Share Posted June 19, 2016 4 hours ago, YNM said: EDIT 2 : More research, ESA astronauts described Soyuz landings like "roller coaster". So I guess this is normal. Guess that's why SpaceX wanted powered landings. Chris Hadfield described Soyuz landings as "fifteen explosions followed by a car crash". Link to comment Share on other sites More sharing options...
Motokid600 Posted June 19, 2016 Share Posted June 19, 2016 I can't make out a single piece. Link to comment Share on other sites More sharing options...
CatastrophicFailure Posted June 19, 2016 Share Posted June 19, 2016 18 minutes ago, Motokid600 said: I can't make out a single piece. That'll buff right out... Link to comment Share on other sites More sharing options...
wumpus Posted June 20, 2016 Share Posted June 20, 2016 9 hours ago, YNM said: Hmm, but Apollo, Orion and Soyuz doesn't rock that hard... EDIT : Ah, explained by Kryten. EDIT 2 : More research, ESA astronauts described Soyuz landings like "roller coaster". So I guess this is normal. Guess that's why SpaceX wanted powered landings. Except that Dragon (the bit for live crew inside) splashes down after a parachute descent. No idea if that changes with the crewed variety (they do that with the cargo variety (1.0), the manned 2.0 should have small changes), but I doubt it. SpaceX only seems to use powered landings for the unmanned booster. Link to comment Share on other sites More sharing options...
CatastrophicFailure Posted June 20, 2016 Share Posted June 20, 2016 So... did anyone notice that a certain ahem competitor of SpaceX has jumped on the live webcast bandwagon? Link to comment Share on other sites More sharing options...
magnemoe Posted June 20, 2016 Share Posted June 20, 2016 42 minutes ago, wumpus said: Except that Dragon (the bit for live crew inside) splashes down after a parachute descent. No idea if that changes with the crewed variety (they do that with the cargo variety (1.0), the manned 2.0 should have small changes), but I doubt it. SpaceX only seems to use powered landings for the unmanned booster. Think dragon 2 will do ground landing with parachutes and engines to land soft. Link to comment Share on other sites More sharing options...
Arcturusvfx Posted June 20, 2016 Share Posted June 20, 2016 those legs look as if they were sheared in half....wow. Link to comment Share on other sites More sharing options...
CptRichardson Posted June 20, 2016 Share Posted June 20, 2016 (edited) 24 minutes ago, Arcturusvfx said: those legs look as if they were sheared in half....wow. Major fire. Aluminum burns. More interesting is the revelations of what else the rocket is made of. I'm actually rather interested in the way the remaining skin flaps like that. It seems to be some sort of carbon fiber layer or something? Doesn't seem to actually be much metal in it. Metal frame, possibly aluminum or titanium, and what looks to be carbon fiber or some other kind of synthetic skin instead of a sheet metal skin. Might explain how it's so light and has such a high payload fraction. Edited June 20, 2016 by CptRichardson Link to comment Share on other sites More sharing options...
PB666 Posted June 20, 2016 Share Posted June 20, 2016 24 minutes ago, Arcturusvfx said: those legs look as if they were sheared in half....wow. It think its rather obvious that the heat warped the structural and it crumpled over, given that rocket was upright for a considerable period and burning. Link to comment Share on other sites More sharing options...
kerbiloid Posted June 20, 2016 Share Posted June 20, 2016 1 hour ago, magnemoe said: Think dragon 2 will do ground landing with parachutes and engines to land soft. Afaik, NASA requirement is to land by chutes. Probably, this means — to splash (i.e. to can do it by chutes only). Of course, they can use engines to soften, but if splashing — it makes not much sense, while if landing — it means significant change of contract conditions. Link to comment Share on other sites More sharing options...
Wingman703 Posted June 20, 2016 Share Posted June 20, 2016 4 hours ago, CatastrophicFailure said: So... did anyone notice that a certain ahem competitor of SpaceX has jumped on the live webcast bandwagon? SpaceX is not exactly the pioneer of live launch broadcasts. I remember seeing shuttle launches live on TV. Link to comment Share on other sites More sharing options...
magnemoe Posted June 20, 2016 Share Posted June 20, 2016 5 hours ago, kerbiloid said: Afaik, NASA requirement is to land by chutes. Probably, this means — to splash (i.e. to can do it by chutes only). Of course, they can use engines to soften, but if splashing — it makes not much sense, while if landing — it means significant change of contract conditions. Chutes does not imply splashdown, only that nasa don't want an powered landing. However I have no idea how detailed the contract is Link to comment Share on other sites More sharing options...
Streetwind Posted June 20, 2016 Share Posted June 20, 2016 (edited) 7 hours ago, CatastrophicFailure said: So... did anyone notice that a certain ahem competitor of SpaceX has jumped on the live webcast bandwagon? 3 hours ago, Wingman703 said: SpaceX is not exactly the pioneer of live launch broadcasts. I remember seeing shuttle launches live on TV. That, and they are also not competitors. Neither company offers anything the other company currently offers. Which may change in the future with Blue Origin's planned orbital launcher But right now these two are not even in the same market. Edited June 20, 2016 by Streetwind Link to comment Share on other sites More sharing options...
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