Xd the great Posted April 21, 2019 Share Posted April 21, 2019 22 minutes ago, Ignath said: said complete/near-complete loss of vehicle. N2O4 running over the length of the entire vehicle is gonna destroy everything. Quote Link to comment Share on other sites More sharing options...
StrandedonEarth Posted April 21, 2019 Share Posted April 21, 2019 Definitely not a good day for Dragon... Quote Link to comment Share on other sites More sharing options...
Arcturusvfx Posted April 21, 2019 Share Posted April 21, 2019 (edited) https://twitter.com/Astronut099/status/1119825093742530560 Edited April 21, 2019 by Arcturusvfx Quote Link to comment Share on other sites More sharing options...
.50calBMG Posted April 21, 2019 Share Posted April 21, 2019 Well, better to get the failures out when they are on the ground rather than in flight, I guess. Quote Link to comment Share on other sites More sharing options...
MinimumSky5 Posted April 21, 2019 Share Posted April 21, 2019 Is it just me, or did that explosion happen near the top of the capsule? Superdraco engine breaks off and shoots through the capsule like a bullet, exiting out of the docking ring? Quote Link to comment Share on other sites More sharing options...
Xd the great Posted April 21, 2019 Share Posted April 21, 2019 36 minutes ago, MinimumSky5 said: Is it just me, or did that explosion happen near the top of the capsule? Superdraco engine breaks off and shoots through the capsule like a bullet, exiting out of the docking ring? Next generation LES: Launches you through the capsule instad of launching the capsule through the sky. Quote Link to comment Share on other sites More sharing options...
Canopus Posted April 21, 2019 Share Posted April 21, 2019 Interesting that now both Boeing and SpaceX had a failure in their liquid propellant fueled LES system. Might have all went a little faster with the good old Solids. Quote Link to comment Share on other sites More sharing options...
tater Posted April 21, 2019 Share Posted April 21, 2019 Course this capsule also took a swim, maybe salt water got into someplace it shouldn't have. Quote Link to comment Share on other sites More sharing options...
sh1pman Posted April 21, 2019 Share Posted April 21, 2019 Its great that this happened during a static fire and not in a real abort event. Quote Link to comment Share on other sites More sharing options...
Canopus Posted April 21, 2019 Share Posted April 21, 2019 @sh1pman It’s great that no one was harmed, on the other hand, they had years of testing, this problem appearing now seems like it could be a big setback. Quote Link to comment Share on other sites More sharing options...
kerbiloid Posted April 21, 2019 Share Posted April 21, 2019 11 hours ago, Xd the great said: N2O4 running over the length of the entire vehicle is gonna destroy everything. Spoiler Quote Link to comment Share on other sites More sharing options...
StrandedonEarth Posted April 21, 2019 Share Posted April 21, 2019 8 hours ago, Arcturusvfx said: https://twitter.com/Astronut099/status/1119825093742530560 Wow. I guess I shouldn't have hid those Easter eggs there... To paraphrase one of the replies in that twitter, "Dragon is Dra-gone!" Quote Link to comment Share on other sites More sharing options...
kerbiloid Posted April 21, 2019 Share Posted April 21, 2019 (edited) Spoiler Dragons are for Targaryens only. Edited April 21, 2019 by kerbiloid Quote Link to comment Share on other sites More sharing options...
Cunjo Carl Posted April 21, 2019 Share Posted April 21, 2019 frames 1-3. Images taken from video posted by Astronut099 on Twitter, brought up here by @Arcturusvfx Hm. Bit of a hard start there. Was curious, so I plotted where the center of the explosion appeared to originate from. Quote Link to comment Share on other sites More sharing options...
magnemoe Posted April 21, 2019 Share Posted April 21, 2019 2 minutes ago, Cunjo Carl said: frames 1-3. Images taken from video posted by Astronut099 on Twitter, brought up here by @Arcturusvfx Hm. Bit of a hard start there. Was curious, so I plotted where the center of the explosion appeared to originate from. Hint, do not mess up the abort and self destruct systems. Quote Link to comment Share on other sites More sharing options...
StrandedonEarth Posted April 21, 2019 Share Posted April 21, 2019 13 minutes ago, magnemoe said: Hint, do not mess up the abort and self destruct systems. Same control panel designer? (Ronald Reagan's finger in screengrab from "Land of Confusion" by Genesis) Quote Link to comment Share on other sites More sharing options...
tater Posted April 21, 2019 Share Posted April 21, 2019 While Musk had said water didn't get in, what makes these Super Dracos different than all the others tested? Reentry? All it would take is a tiny expansion to make a leak someplace. You'd assume that before static firing these they'd pressure test them with something inert. Quote Link to comment Share on other sites More sharing options...
kerbiloid Posted April 21, 2019 Share Posted April 21, 2019 Spoiler Somebody said "Drakaris." Quote Link to comment Share on other sites More sharing options...
Cunjo Carl Posted April 21, 2019 Share Posted April 21, 2019 11 hours ago, tater said: Course this capsule also took a swim, maybe salt water got into someplace it shouldn't have. Seems like a distinct possibility. MMH seems to be catalytic decomposed by low levels of chlorides of Ni and Fe, the components of the inconel the superdracos are printed from, and likely materials used in valves and pipes as well. From: Survey- Monomethylhydrazine Propellant/Material Compatibility- DTIC " Small amounts (0.003M) of disolved nickel and iron increased the decomposition rate of MMH by a factor of 10 at 100'C. ""...the addition of 1 percent NH4Cl increased the rate of MMH decomposition at 200"C in Pyrex by a factor of 100 - a more pronounced effect than that observed with hydrazine." Though inconel is corrosion resistant, it's definitely not corrosion proof- especially in the face of sea water and salty breeze. Given this, I could totally imagine corroded metal surfaces kicking off a thermal runaway shortly after the lines were pressurized, but _before_ the MMH started flowing. This would make the most sense for an exposed valve surface like a face-shutoff valve used on the pintle injector in the Merlins. Any idea if this same system is used on the Dracos? It'd sure make sense to use it here, where simplicity and speed of startup are the top priorities. Quote Link to comment Share on other sites More sharing options...
Cuky Posted April 21, 2019 Share Posted April 21, 2019 1 hour ago, tater said: While Musk had said water didn't get in, what makes these Super Dracos different than all the others tested? Reentry? All it would take is a tiny expansion to make a leak someplace. You'd assume that before static firing these they'd pressure test them with something inert. Well, they had few successful tests on that same day before that last one where things went boom Quote Link to comment Share on other sites More sharing options...
tater Posted April 21, 2019 Share Posted April 21, 2019 Just now, Cuky said: Well, they had few successful tests on that same day before that last one where things went boom I read they had tested the Dracos, but it was unclear if they had yet tested the Super Dracos. Quote Link to comment Share on other sites More sharing options...
Xd the great Posted April 22, 2019 Share Posted April 22, 2019 6 hours ago, tater said: While Musk had said water didn't get in, what makes these Super Dracos different than all the others tested? Reentry? All it would take is a tiny expansion to make a leak someplace. You'd assume that before static firing these they'd pressure test them with something inert. Maybe the inert test broke it... Quote Link to comment Share on other sites More sharing options...
Xd the great Posted April 22, 2019 Share Posted April 22, 2019 5 hours ago, Cunjo Carl said: Seems like a distinct possibility. MMH seems to be catalytic decomposed by low levels of chlorides of Ni and Fe, the components of the inconel the superdracos are printed from, and likely materials used in valves and pipes as well. From: Survey- Monomethylhydrazine Propellant/Material Compatibility- DTIC " Small amounts (0.003M) of disolved nickel and iron increased the decomposition rate of MMH by a factor of 10 at 100'C. ""...the addition of 1 percent NH4Cl increased the rate of MMH decomposition at 200"C in Pyrex by a factor of 100 - a more pronounced effect than that observed with hydrazine." Though inconel is corrosion resistant, it's definitely not corrosion proof- especially in the face of sea water and salty breeze. Given this, I could totally imagine corroded metal surfaces kicking off a thermal runaway shortly after the lines were pressurized, but _before_ the MMH started flowing. This would make the most sense for an exposed valve surface like a face-shutoff valve used on the pintle injector in the Merlins. Any idea if this same system is used on the Dracos? It'd sure make sense to use it here, where simplicity and speed of startup are the top priorities. Yep, if i remember correctly it is a pintle injector. Also, 3D printed, so that might be a problem. Quote Link to comment Share on other sites More sharing options...
SpacePigeon Posted April 22, 2019 Share Posted April 22, 2019 Looking at the link from @Arcturusvfx, it seems that SpaceX hasn't cleaned the capsule. With this, I decided to compare images to the landed Dragon 2 from DM1. Spoiler This frame from the Dragon landing shows one side of the Dragon being significantly darkened along with no hatches or windows. Spoiler While this picture shows the hatch side being much lighter. Now the capsule here has a lighter side facing the camera and the burnt parts here matching the burnt parts on the recovery image of the hatch side. My opinion is that the explosion didn't come from the SuperDracos. The explosion isn't centered on any engine pod (being centered at the area below and right of the hatch) and that the Dragon 2 is supposed to be able to operate after a catastrophic engine failure. (Scott Manley's take: https://twitter.com/DJSnM/status/1119860405461864448) The muffled audio also sounds like someone counting down with the explosion occurring after 9. Ignition would be later on and on the Dragon abort test, the sound suppression system would've started. I found an interesting picture for the internals. Dragon without a shell (from SpaceX's insta, https://www.instagram.com/p/BucYA72AYJ1/): Spoiler ll Quote Link to comment Share on other sites More sharing options...
kerbiloid Posted April 22, 2019 Share Posted April 22, 2019 Should the visible center of the hot gas cloud match the visible projection of the center of the explosion process? We can see where the gas cloud breaks out through the weakest place of the hull, but not where the explosive has exploded. Quote Link to comment Share on other sites More sharing options...
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