StrandedonEarth Posted September 7, 2017 Share Posted September 7, 2017 Congrats to SpaceX on another successful launch and recovery!! Quote Link to comment Share on other sites More sharing options...
Skylon Posted September 7, 2017 Author Share Posted September 7, 2017 I missed it (was during school here, half an hour too late for lunch) Quote Link to comment Share on other sites More sharing options...
KSK Posted September 7, 2017 Share Posted September 7, 2017 Lovely! Although you know you've watched too many of these when you see the grid fins deploy and think 'yup - those are the new titanium ones', before the commentator manages to get a word in. Quote Link to comment Share on other sites More sharing options...
StupidAndy Posted September 7, 2017 Share Posted September 7, 2017 1 hour ago, KSK said: Lovely! Although you know you've watched too many of these when you see the grid fins deploy and think 'yup - those are the new titanium ones', before the commentator manages to get a word in. those were the titanium ones? they looked normal...or maybe I am thinking the titanium ones look like the non-titanium ones Quote Link to comment Share on other sites More sharing options...
TheEpicSquared Posted September 7, 2017 Share Posted September 7, 2017 Looked like the normal ones to me too. I recognize the titanium ones with the new design at the top where it's attached to the body, it kind of looks like a pair of angry eyes (marked with a box in the picture below (the right side grid fin is the titanium one)) Quote Link to comment Share on other sites More sharing options...
sevenperforce Posted September 7, 2017 Share Posted September 7, 2017 The titanium ones are also significantly thicker. Quote Link to comment Share on other sites More sharing options...
StupidAndy Posted September 7, 2017 Share Posted September 7, 2017 (edited) I (un)officially now rename the grid fins the "angry eyes" grid fins! Edited September 7, 2017 by StupidAndy well i DONT work for spacex..so Quote Link to comment Share on other sites More sharing options...
Grand Ship Builder Posted September 8, 2017 Share Posted September 8, 2017 And the titanium fins are also darker! And 2 + 1 = yes. Quote Link to comment Share on other sites More sharing options...
Ultimate Steve Posted September 8, 2017 Share Posted September 8, 2017 Darn school internet filter, I missed this one. Quote Link to comment Share on other sites More sharing options...
Scotius Posted September 8, 2017 Share Posted September 8, 2017 I got a new computer...YAAAY! Oh no... i missed SpaceX launch because i was busy installing the system and all assorted doodads Oh well - YT to the rescue. Quote Link to comment Share on other sites More sharing options...
CatastrophicFailure Posted September 8, 2017 Share Posted September 8, 2017 I see on spaceflightnow that SES11 et al is now scheduled for October 2... still from 39A... Assuming the whole place doesn't wash away before then. Quote Link to comment Share on other sites More sharing options...
YNM Posted September 8, 2017 Share Posted September 8, 2017 One question : the last launch didn't show where the second stage gone to. Is it because of contract obligations or what ? Quote Link to comment Share on other sites More sharing options...
StarStreak2109 Posted September 8, 2017 Share Posted September 8, 2017 Classified payload. Quote Link to comment Share on other sites More sharing options...
Technical Ben Posted September 8, 2017 Share Posted September 8, 2017 (edited) On 04/09/2017 at 4:13 PM, Elthy said: The X-37B is a payload, not the second stage. BTW: What happened to the extra pictures Elon promised us? " More in days to follow. " doesnt sound like several weeks... Oh, I know it is... but some duck tape, and a LOT of craft glue and anything is possible. Oh, also I think I have those grid fins at home... we use them to mash potatoes! Edited September 8, 2017 by Technical Ben Quote Link to comment Share on other sites More sharing options...
magnemoe Posted September 8, 2017 Share Posted September 8, 2017 11 hours ago, sevenperforce said: The titanium ones are also significantly thicker. Don't think so, more about the angle of the photo, the titanium should be thinner as its an far stronger material. Look at the left edge as its straight on. Quote Link to comment Share on other sites More sharing options...
Nibb31 Posted September 8, 2017 Share Posted September 8, 2017 The whole point of a grid fin is that it has to be thick, otherwise it's not a fin. Quote Link to comment Share on other sites More sharing options...
magnemoe Posted September 8, 2017 Share Posted September 8, 2017 36 minutes ago, Nibb31 said: The whole point of a grid fin is that it has to be thick, otherwise it's not a fin. fin need to be of some size yes, however the material thinness is unimportant, you can make them of sheet metal if it can handle the load.https://en.wikipedia.org/wiki/Grid_fin#/media/File:MOAB_grid_fins.jpg Yes the falcon 9 ones need to handle reentry heat so they need to be far more sturdy. the raised cross sections is probably for better supersonic handling. Main surprise is how thin they are. Quote Link to comment Share on other sites More sharing options...
cubinator Posted September 8, 2017 Share Posted September 8, 2017 3 hours ago, Technical Ben said: Oh, also I think I have those grid fins at home... we use them to mash potatoes! Those are some big potatoes... Quote Link to comment Share on other sites More sharing options...
sevenperforce Posted September 8, 2017 Share Posted September 8, 2017 4 hours ago, magnemoe said: Don't think so, more about the angle of the photo, the titanium should be thinner as its an far stronger material. Look at the left edge as its straight on. I meant thickness of the airfoil structure, not thickness of the titanium metal pieces. Thicker = protrudes farther from the edge of the stage. The mini-airfoils have a longer chord length. The titanium airfoils are not only longer, catching a greater cross-sectional area of the airstream, but they are also "thicker" and thus provide a longer path for air to flow through, increasing the amount of lift they can effect. Quote Link to comment Share on other sites More sharing options...
magnemoe Posted September 8, 2017 Share Posted September 8, 2017 12 minutes ago, sevenperforce said: I meant thickness of the airfoil structure, not thickness of the titanium metal pieces. Thicker = protrudes farther from the edge of the stage. The mini-airfoils have a longer chord length. The titanium airfoils are not only longer, catching a greater cross-sectional area of the airstream, but they are also "thicker" and thus provide a longer path for air to flow through, increasing the amount of lift they can effect. Understand, easy to get confused here also because of language, thinness I think of as width mostly, with your thickness would be my depth. The titanium also has an structure there the intersections has points. has not seen this on other grind fins. Quote Link to comment Share on other sites More sharing options...
monophonic Posted September 8, 2017 Share Posted September 8, 2017 1 hour ago, cubinator said: Those are some big potatoes... Are those anti-pidgeon spikes attached on a strip to the grid fin? Quote Link to comment Share on other sites More sharing options...
Racescort666 Posted September 8, 2017 Share Posted September 8, 2017 It's entirely possible that they increased the size to handle the heat as well (just spit balling here). More mass = more heat capacity = less degradation from heating. I'm sure the increased temperature limit of the titanium doesn't hurt either. Quote Link to comment Share on other sites More sharing options...
sevenperforce Posted September 8, 2017 Share Posted September 8, 2017 19 minutes ago, magnemoe said: Understand, easy to get confused here also because of language, thinness I think of as width mostly, with your thickness would be my depth. The titanium also has an structure there the intersections has points. has not seen this on other grind fins. Ah, gotcha. We should standardize. Quote Link to comment Share on other sites More sharing options...
YNM Posted September 8, 2017 Share Posted September 8, 2017 (edited) Yeah, it should be depth. The point of grid fins are to minimise weight and increasing area, so thinness of the materials isn't a problem - in fact you want it - but you want some, or a lot, of depth. Anyway, I think SpaceX have found a neat way to distract people from noting where classified payloads go. Would it make them more favorable from DoD ? Edited September 8, 2017 by YNM Quote Link to comment Share on other sites More sharing options...
sevenperforce Posted September 8, 2017 Share Posted September 8, 2017 30 minutes ago, YNM said: Anyway, I think SpaceX have found a neat way to distract people from noting where classified payloads go. Would it make them more favorable from DoD ? I'm sure there are lots of space jockeys out there tracking the X-37B now. Aaaaaand based on discussions over at the NSF forums, these are the aluminum grid fins, not the titanium ones after all. Looks like the commentator misspoke. Surprised, because I thought this was supposed to be a Block 4 rocket. Maybe they just had extra aluminum grid fins and wanted to burn through them (literally?) on low-stress launches like this one? Quote Link to comment Share on other sites More sharing options...
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