Delay Posted May 31, 2020 Share Posted May 31, 2020 And there's the answer to my question from yesterday: Dragon is a very smooth vehicle during liftoff! Quote Link to comment Share on other sites More sharing options...
YNM Posted May 31, 2020 Share Posted May 31, 2020 (edited) 37 minutes ago, Delay said: You can't operate space stations with 90s tech forever. Fingers crossed man ! Soyuz controls of the current MS era looks pretty good as well. Capacitive sensors - the technology behind touchscreens - are actually pretty resilient; screens could be cracked but the risks can be evaluated well. 23 minutes ago, Delay said: And there's the answer to my question from yesterday: Dragon is a very smooth vehicle during liftoff! They say it's more "alive" - probably from the two peak-g. Edited May 31, 2020 by YNM Quote Link to comment Share on other sites More sharing options...
Delay Posted May 31, 2020 Share Posted May 31, 2020 9 minutes ago, YNM said: They says it's more "alive" Not surprising, it's a Dragon after all. The lack of SRBs does make for a smoother ride, however. Of course you have two bumps - MECO and S2 ignition. Quote Link to comment Share on other sites More sharing options...
Nothalogh Posted May 31, 2020 Share Posted May 31, 2020 Does anybody know what pants the DM2 crew are wearing when not in their suits? Quote Link to comment Share on other sites More sharing options...
Nothalogh Posted May 31, 2020 Share Posted May 31, 2020 1 hour ago, YNM said: They say it's more "alive" - probably from the two peak-g. Higher upper stage TWR than Shuttle, this is probably more comparable to Gemini on a Titan Quote Link to comment Share on other sites More sharing options...
Shpaget Posted May 31, 2020 Share Posted May 31, 2020 So Shuttle was quite shaky in early stages, but once the SRBs burn out, it's fairly smooth, compared to F9 which is not quite as shaky, but shaky all the way? Could it be down to pure mass; higher mass of Shuttle dampening vibrations? 1 hour ago, Nothalogh said: Does anybody know what pants the DM2 crew are wearing when not in their suits? Here's the answer from an ISS astronaut: https://www.quora.com/Where-can-I-buy-clothes-like-the-ISS-astronauts-wear NASA attached the velcros, but it's basically this: https://www.cabelas.com/product/Clothing/Mens-Casual-Clothing/Mens-Casual-Pants/Mens-Cargo-Pants|/pc/104797080/c/104746680/sc/104262480/i/104076180/Cabelas-Legendary-7-Pocket- Hiker-Pants/1323177.uts?destination=/category/Mens-Cargo-Pants/104076180.uts Sold out, of course. Quote Link to comment Share on other sites More sharing options...
magnemoe Posted May 31, 2020 Share Posted May 31, 2020 2 hours ago, Delay said: Not surprising, it's a Dragon after all. The lack of SRBs does make for a smoother ride, however. Of course you have two bumps - MECO and S2 ignition. Yes also the shuttle has weird aerodynamic during launch. Basically all the not to do stuff for an KSP rocket Don't know about Soyuz but its an old design pretty sure falcon 9 has better engine control. Quote Link to comment Share on other sites More sharing options...
YNM Posted May 31, 2020 Share Posted May 31, 2020 1 hour ago, Nothalogh said: Higher upper stage TWR than Shuttle, this is probably more comparable to Gemini on a Titan I was actually wondering about that short >4g moments, but I guess it's fine. Quote Link to comment Share on other sites More sharing options...
StrandedonEarth Posted May 31, 2020 Share Posted May 31, 2020 Quote Link to comment Share on other sites More sharing options...
EchoLima Posted May 31, 2020 Share Posted May 31, 2020 Here's my version of the launch: Quote Link to comment Share on other sites More sharing options...
Jacke Posted May 31, 2020 Share Posted May 31, 2020 (edited) 10 hours ago, sh1pman said: If only you guys could see the crazy ****storm happening right now in Russian social media after this launch and Elon’s comment about trampoline. People from all political sides bashing Rogozin and Roscosmos for incompetence. My entire feed turned into space experts’ battleground. Looks like Elon has much more support here than I thought. What's this about "trampoline" ? I'm assuming it's not this. I'm no great fan of Elon and he has said some very stupid things in the past. He has gotten better at not screwing up, so I'll give him the benefit of the doubt until I hear otherwise. 6 hours ago, Delay said: We all missed this, didn't we? I definitely want to see that suit! Sigh, always "The Fruit of the Month". Did you ever stop to think that big Kerbal helmet might be functional? How do you think they fix things in space and usually so quickly? They beat their heads on it. Huge helmet => frustrating part => problem solved! Edited May 31, 2020 by Jacke Quote Link to comment Share on other sites More sharing options...
Spaceception Posted May 31, 2020 Share Posted May 31, 2020 8 minutes ago, Jacke said: What's this about "trampoline" ? I'm assuming it's not this. I'm no great fan of Elon and he has said some very stupid things in the past. He has gotten better at not screwing up, so I'll give him the benefit of the doubt until I hear otherwise. It was a reference to this From 2014 Quote Link to comment Share on other sites More sharing options...
Xd the great Posted May 31, 2020 Share Posted May 31, 2020 Does crew dragon have any toilets? I mean, wearing the same diaper for 19 hours/2 days is... uncomfortable. Quote Link to comment Share on other sites More sharing options...
Dirkidirk Posted June 1, 2020 Share Posted June 1, 2020 11 minutes ago, Xd the great said: Does crew dragon have any toilets? yes. 11 minutes ago, Xd the great said: wearing the same diaper for 19 hours/2 days is... uncomfortable. yes... Quote Link to comment Share on other sites More sharing options...
Nothalogh Posted June 1, 2020 Share Posted June 1, 2020 15 minutes ago, Xd the great said: Does crew dragon have any toilets? Yes, there was a whole discussion on the livestream of using an extra bottle of water when they flush it. Quote Link to comment Share on other sites More sharing options...
RealKerbal3x Posted June 1, 2020 Share Posted June 1, 2020 SN5 gets ready, a new test stand arrives, and the SpaceX team remove some shrapnel! Quote Link to comment Share on other sites More sharing options...
sh1pman Posted June 1, 2020 Share Posted June 1, 2020 19 hours ago, Nothalogh said: Why, and for what purpose? Rogozin sometimes talks too much. That, and the general lack of innovation in Russian space industry for the past 30 years. Crew Dragon launch further illustrated this growing lag. Quote Link to comment Share on other sites More sharing options...
Lukaszenko Posted June 1, 2020 Share Posted June 1, 2020 (edited) Man of many talents! Edited June 1, 2020 by Lukaszenko Quote Link to comment Share on other sites More sharing options...
RealKerbal3x Posted June 1, 2020 Share Posted June 1, 2020 SpaceX uploaded the full video of the Demo-2 launch, if you wanted to watch it again: Quote Link to comment Share on other sites More sharing options...
sevenperforce Posted June 1, 2020 Share Posted June 1, 2020 22 hours ago, YNM said: Pretty sure they do on the ISS as well ! As long as you can generate enough suction, you can still drink well from an enclosed bottle. Or you can just squeeze it. Only thing easier to drink from would be a flattenable pouch. Quote Link to comment Share on other sites More sharing options...
RealKerbal3x Posted June 1, 2020 Share Posted June 1, 2020 8 minutes ago, sevenperforce said: Or you can just squeeze it. Only thing easier to drink from would be a flattenable pouch. I think they normally use pouches for drinks on ISS for that reason. It's the easiest thing to drink from in microgravity. Quote Link to comment Share on other sites More sharing options...
sevenperforce Posted June 1, 2020 Share Posted June 1, 2020 (edited) 20 hours ago, Nothalogh said: Higher upper stage TWR than Shuttle, this is probably more comparable to Gemini on a Titan Minimum throttle on the Soyuz-FG's RD-0110 upper stage engine is 90.5% of its 298 kN, or 269.69 kN, which is a burnout acceleration of 2.89 gees (7.1 tonne payload, 2.4 tonne upper stage). Merlin 1D Vac can throttle down to about 2.45 gees at burnout with the higher mass of Dragon. I did a frame-by-frame count of velocity just before first-stage burnout, around T+02:26, and got 23.9 m/s2 or 2.44 gees. The Shuttle limited its burnout thrust to 3 gees. EDIT: See below; S2 burnout was nearly 4 gees. Edited June 1, 2020 by sevenperforce Quote Link to comment Share on other sites More sharing options...
tater Posted June 1, 2020 Share Posted June 1, 2020 Quote Link to comment Share on other sites More sharing options...
sevenperforce Posted June 1, 2020 Share Posted June 1, 2020 (edited) I just did a frame-by-frame count of the end of the second-stage burn, from T+08:49 to T+08:50, and got a whopping 39.2 m/s2 just before SECO. That's almost four gees. So evidently they did not downthrottle very far...especially given that we know they had ample residuals. If we assume an 18-tonne burnout mass (12 tonnes of capsule, 4 tonnes of dry mass, 2 tonnes of props) then that is 705.6 kN, which is about 75.5% full thrust. Edited June 1, 2020 by sevenperforce Quote Link to comment Share on other sites More sharing options...
cubinator Posted June 1, 2020 Share Posted June 1, 2020 Just now, sevenperforce said: I just did a frame-by-frame count of the end of the second-stage burn, from T+08:49 to T+08:50, and got a whopping 39.2 m/s2 just before SECO. That's almost four gees. So evidently they did not downthrottle very far...especially given that we know they had ample residuals. If we assume an 18-tonne burnout mass (12 tonnes of capsule, 4 tonnes of dry mass, 2 tonnes of props) then that is 705.6 kN, which is about 75.5% full thrust. I recall the astronauts themselves saying they got about 4.8 gees. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.