In-Flight Abort Test Press Kit
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Submitted January 17, 2020 at 02:10PM by Straumli_Blight
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SpaceX on Twitter: Falcon 9 and Crew Dragon vertical ahead of tomorrow’s in-flight demonstration
https://twitter.com/SpaceX/status/1218153687429705730

Submitted January 17, 2020 at 02:09PM by xDeeKay
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<b>r/SpaceX In-Flight Abort Test Official Launch Discussion & Updates Thread</b>
<a href="/#%20MC%20//%20section%20intro">IntroductionWelcome, all the people of the subreddit! It is the mod team that is going to bring you live updates on the long awaited In-Flight Abort Test.Your host teamReddit usernameTwitter accountResponsibilitiesNumber of hosts<a href="/u/hitura-nobad">u/hitura-nobad<a href="https://twitter.com/HituraNobad">@HituraNobadMission updates, Community? Hostu/Nsooo<a href="https://twitter.com/TheRealNsooo">@TheRealNsoooThread format, Mission updates? HostAbout the missionSpaceX is going to simulate an abort around Max-Q, when Crew Dragon will use it's Superdraco engines to escape from the failing booster.The triple flown booster is going to be destroyed by aerodynamics.Scrub counterScrub dateCauseCountdown stoppedBackup dateNo scrubs!n/an/an/aLot of facts&#9745;&#65039; This will be the <strong>87th</strong> SpaceX launch.&#9745;&#65039; This will be the <strong>79th</strong> Falcon 9 launch.&#9745;&#65039; This will be the <strong>23rd</strong> Falcon 9 Block 5 launch.&#9745;&#65039; This will be the <strong>2nd</strong> SpaceX launch this year.&#9745;&#65039; This will be the <strong>2nd</strong> Falcon 9 launch this year.&#9745;&#65039; This will be the <strong>4th</strong> and last flight of the flight-proven Block 5 core B1046.&#9745;&#65039; This will be the heaviest payload launched on a <strong>suborbital trajectory</strong> by SpaceXVehicles usedTypeNameLocationFirst stageFalcon 9 v1.2 - Block 5 (Full Thrust) - B1056KSC, LC-39ASecond stageFalcon 9 v1.2 Block 5 (<em>No thrust this time</em>)KSC, LC-39A<em>Core data source: Core wiki by r/SpaceX</em><em>Ship data source: SpaceXFleet by u/Gavalar_</em>Live updates<a href="/#%20MC%20//%20section%20events">TimelineTimeUpdate<a href="/#%20MC%20//%20row%2029"> T-21:00:00Welcome everyone! Falcon 9 went vertical ahead of tomorrows launch attempt. Currently GO for launch!<a href="/#%20MC%20//%20section%20viewing">Mission's state&#9989; Currently <strong>GO</strong> for the launch attempt.Weather - Cape Canaveral, FloridaLaunch windowWeatherTemperatureProb. of rainProb. of weather scrubMain concernPrimary launch window<strong>&#127780;&#65039;</strong> <em>Partly Cloudy</em><strong>&#127777;&#65039;</strong> <em>No data</em><strong>&#128167;</strong> <em>No data</em><strong>&#128721;</strong> <em>10%</em><em>No data</em><em>Weather data source: Google Weather & 45th Space Wing.</em> <em>- The probability of a scrub due to weather does not includes the chance due to upper level winds, which are monitored by the SpaceX launch team itself using sounding balloons before launch.</em><a href="/#%20MC%20//%20section%20stats">Watching the launch liveLinkNote<a href="https://www.spacex.com/webcast">Official SpaceX Launch Webcast - embeddedstarting ~20 minutes before liftoff<a href="https://www.youtube.com/watch?v=sbXgZg9JmkI">Official SpaceX Launch Webcast - directstarting ~20 minutes before liftoff<a href="https://www.reddit.com/r/spacex/comments/ebfr9t/rspacex_jcsat18kacific1_official_launch/fb4kdie/">Webcast - relay<a href="/u/codav">u/codav<a href="/#%20MC%20//%20section%20mission">Useful Resources, Data, &#9835;, & FAQEssentialsLinkSource<a href="http://www.spacex.com/sites/spacex/files/in-flight_abort_test_press_kit.pdf">Press kit<a href="http://www.spacex.com">SpaceXLaunch weather forecast<a href="http://www.patrick.af.mil/About-Us/Weather/">45th Space Wing<a href="https://www.spacexfleet.com/next">SpaceX Fleet StatusSpaceXFleet.comSocial mediaLinkSource<a href="https://reddit.com/r/SpaceX">Reddit launch campaign thread<a href="/r/SpaceX">r/SpaceX<a href="https://twitter.com/rSpaceX">Subreddit Twitter<a href="/r/SpaceX">r/SpaceX<a href="https://twitter.com/SpaceX">SpaceX Twitter<a href="/r/SpaceX">r/SpaceX<a href="https://www.flickr.com/photos/spacex/">SpaceX Flickr<a href="/r/SpaceX">r/SpaceX<a href="https://twitter.com/elonmusk">Elon Twitter<a href="/r/SpaceX">r/SpaceX<a…

<b>[Sources Required] What's preventing SpaceX from recovering B1046 in the In Flight Abort Test</b>
Elon <a href="https://twitter.com/elonmusk/status/1216148212085428224">said</a> that they've tried to find a way to recover the first stage but couldn't find any way to do it. Let's see why by trying to design a recovery trajectory.On T+1:33 Dragon aborts. The abort itself won't affect the Falcon 9 because Dragon will be lifted by the SuperDraco engines.But it exposes the second stage to the supersonic flow of air.Can the stack survive the supersonic flow or air?The force on the second stage before the abort:<code>Drag with Dragon = 0.5 * p * v^2 * Cd * Area = 0.5 * 0.04 * 666^2 * 0.25 * 10.8 = 24,000 N</code>[1] [2]<code>Dragon's weight = 9.8 * 9,525 = 152145 N</code> [3]=> Total force on stage 2 = drag + dragon's weight = <code>24000 N + 152145 N = 176,145 N</code><code>Drag without Dragon = 0.5 * p * v^2 * Cd * Area = 0.5 * 0.04008 * 666^2 * 0.8 * 10.8 = 76,800 N</code> [4]This means the total force on stage 2 after the abort will be half as much as it will with Dragon. This doesn't prove Falcon 9 will not be torn due to aerodynamic forces as the situation is FAR more complex than this simple force calculation. But what I can say is that <strong>Falcon 9 won't be crushed due to drag</strong>.Separation from Stage 2In order to simulate loss of thrust in case of a RUD, Stage 1 will shut off its engines. And only 3 engines are re ignitable, so it can't continue a normal ascent up to MECO like every flight (see "Trajectory after the abort" section). It also can't coast and do a normal landing burn because it has too much fuel (too heavy for the landing legs, wrong CoG) and has a second stage on top of it.Stage 1 has to separate from Stage 2 because it can't land with it (too heavy, ruins aerodynamics and moves the GoG too high), Stage 2 can't be separated on ascent because drag will cause it to slow down faster than stage 1.For example: If stage 1 were to separate from stage 2 right after Dragon's abort, it will headbutt the second stage <a href="https://www.youtube.com/watch?v=v0w9p3U8860&t=2m51s">Falcon 1 Flight 3 style</a> as the second stage decelerates 2.5 m/s2 faster than it.That means <strong>separation has to occur at, or close, to apogee</strong>. This is in addition to the fact the first stage is normally never exposed on ascent. And would probably require a nose cone if it were to be exposed.Trajectory after the abortAccording to FlightClub[2], on abort the first stage will contain 175 tons of propellant. An average landing burn requires ~15 tons of propellant. That means the booster needs to burn 150 tons of propellant in order to land.The Merlin 1D engine has a MFR of 279 kg/s. x3 engines = 837 kg/s.Total burn time = <code>150,000 [kg] / 873 [kg/s] = 171 seconds</code>Upper bound of gravity losses = <code>9.8 * 171 = 1675 m/s</code>Total burn delta v (with S2) = <code>282 * 9.8 * ln([22 + 116 + 150]/[116 + 22]) = 2033 m/s</code> [5]TWR = <code>3*845 [kN] / [9.8*(22,000 + 175,000 + 116,000)] = 0.82</code>This <strong>rules out any attempt to raise apogee</strong> in any major way. It's doubtful the booster can reorient itself engines first in the relatively dense atmosphere at ~50 km.The best approach seems to be a coast to apogee, stage separation the second stage and a continuous burn for the rest of the way.FlightClub[2] shows an apogee of 48 km.delta v (without stage 2) = <code>282 * 9.8 * ln([22 + 150]/22) = 5683 m/s</code>while it seems like the stage has enough performance to land, it would require major software and possible hardware changes. The stage would have to do an almost continuous burn from apogee to landing. The grid fins would have very limited control on the low speed flow, very high center of gravity and fuel sloshing. <strong>It's probably too much effort for SpaceX to try to recover B1046, even though it might be physically possible.</strong>[1] Density of air from: <a href="https://www.enginee…

@elonmusk: Needs to be such that anyone can go [to Mars] if they want, with loans available for those who don’t have money
https://twitter.com/elonmusk/status/1217991853615677440

Submitted January 17, 2020 at 05:43PM by CProphet
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Updated 2019 SLS & Falcon 9 Cost Infographic
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Submitted January 17, 2020 at 06:45PM by DoYouWonda
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[German] "Raumzeit" Podcast with Hans Koenigsmann
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Submitted January 17, 2020 at 12:42PM by toothstone64
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r/SpaceX In-Flight Abort Test Media Thread [Videos, Images, GIFs, Articles go here!]
It's that time again, as per usual, we like to keep things as tight as possible, so if you have content you created to share, whether that be images of the launch, videos, GIF's, etc, they go here.Hosted ThreadIf you want your submission to be added to the table make sure to ping us!ImagesPhotographLinkSpaceXhttps://www.spacex.com/sites/spacex/files/ifa_vertnight0116_dsc_0044.jpgNASAWill be available at https://www.flickr.com/photos/nasahqphoto/VideosCreatorLinkSpaceXhttps://www.youtube.com/watch?v=mhrkdHshb3ENASAhttps://www.youtube.com/watch?v=ARIZnaMXTEUArticlesSourceLinkAs usual, our standard media thread rules apply:All top level comments must consist of an image, video, GIF, tweet or article.If you're an amateur photographer, submit your content here. Professional photographers with subreddit accreditation can continue to submit to the front page, we also make exceptions for outstanding amateur content!Those in the aerospace industry (with subreddit accreditation) can likewise continue to post content on the front page.Mainstream media articles should be submitted here. Quality articles from dedicated spaceflight outlets may be submitted to the front page.Direct all questions to the live launch thread.

Submitted January 17, 2020 at 11:35PM by ElongatedMuskrat
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@jeff_foust: SpaceX’s Benji Reed - the Crew Dragon for the Demo-2 crewed test flight should be completed and delivered to Cape Canaveral by the end of this month.
https://twitter.com/jeff_foust/status/1218244571353710594

Submitted January 17, 2020 at 10:10PM by CProphet
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SpaceX standing down for today’s IFA test launch due to sustained winds and rough seas in recovery area. Window reopens tomorrow 1/19/2020 for a six-hour window starting at 8am.
https://twitter.com/spacex/status/1218473546772430848?s=21

Submitted January 18, 2020 at 11:13AM by tbcheese
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NASA says early March dm2 possible
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Submitted January 18, 2020 at 12:21PM by deadman1204
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Here's why Falcon 9/Heavy 2nd stage is an engineering marvel.
First where did this rant comes from? The trigger is this tweet from someone who has no idea how rocket equation works: https://twitter.com/LCS_Big_Mike/status/1217990754771095561This was also briefly discussed on SpaceXMasterrace here It looks to me that there's a misconception that Falcon 2nd stage is "bad", but is it? A straight forward comparison would tell you otherwise:F9/H 2nd Stage (S2)Centuar III (used on Atlas V)Stage Empty Mass (t)~52Stage Propellant Mass (t)~11120.8Stage Total Mass (t)~11622.8Isp (s)348450Delta-V without payload (m/s)1072210732Delta-V with 1t payload (m/s)101309133Delta-V with 5t payload (m/s)85026081Delta-V with 10t payload (m/s)72584434(Disclaimer: SpaceX doesn't disclose the exact 2nd stage empty or propellant mass, so the numbers here is an estimate, but I think it's a conservative estimate. Source is spacelaunchreport.com: Falcon 9, Atlas V) As you can see, while empty the F9 S2 has basically the same delta-v as the Centuar upper stage on Atlas V, once you start to add payload, the delta-v provided by F9 S2 quickly surpassed Centuar.This is very remarkable since Centuar is using RL10, a hydrolox engine which has much higher Isp than F9 S2's Merlin Vacuum engine, and Centuar uses a pressure stabilized propellant tank which is very mass efficient (but couldn't support itself without pressurization).So how did SpaceX do this? The general answer is that F9 S2 is simply more mass efficient, as measured by Propellant mass fraction (PMF), which is the ratio between the propellant mass and the initial mass of the vehicle. In rocket equation, PMF has the same importance as Isp, but rookies usually focused on Isp and ignores PMF, which is a big mistake.F9 S2's PMF is 95.7% while Centuar's PMF is 91.2%, this is a huge difference when it comes to rocket equation. This means given the same metric ton of vehicle structure, F9 S2 can take a lot more propellant, and thus provide more delta-v. A simple division would show for each metric ton of vehicle structure, F9 S2 can take 22 metric tons of propellant, while Centuar can only take 10.4 metric tons of propellant.The exact method SpaceX used to achieve this remarkable PMF is not spelled out, it's their secret sauce after all, but my guess is it's a combination of:Merlin's superior Thrust-to-weight ratio (TWR)Semi pressure stabilized propellant tank (can support its own weight when unpressurized but need pressure to handle flight load)Sub-cooled propellantCooled Helium storage using COPV inside LOX tank This mass efficient 2nd stage is what's allowing SpaceX to put 5 to 6 metric tons to Geostationary transfer orbit (GTO) using a two stage all kerolox launch vehicle, no other launch vehicle in human history can do this. So next time someone mentions F9 S2 is trash or bad, explain PMF to them and see them squirm.

Submitted January 18, 2020 at 06:17PM by spacerfirstclass
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Starman is at its farthest point from Earth in its orbit.
Today is the farthest that a Tesla has ever been from the earth, till 2022 at least. It's current location is 217,118,543 miles (349,418,532 km, 2.336 AU, 19.43 light minutes) away, on an orbit around the sun that extends beyond the orbit of Mars. https://www.whereisroadster.com/

Submitted January 17, 2020 at 07:59PM by Zero_Waist
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The new trajectory to Mars. The Low-Energy-Transfer. This is exactly the right terrain for SpaceX ...isn't it?
Is SpaceX also discussing the possibility of a new shorter route to Mars?In 2014 Francesco Toputto and Edward Belbruno construct a new type of transfer from the Earth to Mars, which ends in ballistic capture. (https://arxiv.org/abs/1410.8856) It is called the Low-Energy-Transfer (https://en.wikipedia.org/wiki/Low-energy_transfer)Their work caused quite a stir. It would be the alternative to the Hohmann transfer. The short time window, the extreme deceleration manoeuvre, the high propellant velocities... all this would be obsolete after the route Toputto and Belbruno have calculated.The flight duration would be only slightly longer and above all a regular shuttle service to Mars could be established.It would be interesting if flight tests would be started at least once. So far I could not find any further public reports about this. Neither from NASA, ESA nor from SpaceX. The new trajectory was already described in 2014. This is exactly the right terrain for SpaceX ...isn't it?

Submitted January 18, 2020 at 09:57PM by nochnDing
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New T-0 of 10:00 a.m. EST to optimize for decreasing winds in the recovery area
https://twitter.com/SpaceX/status/1218865768428974081?s=19

Submitted January 19, 2020 at 01:09PM by UrbanArcologist
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SpaceX on Twitter: "Now targeting 10:30 a.m. EST; teams are continuing to track weather in the recovery area"
https://twitter.com/SpaceX/status/1218898186162466818?s=19

Submitted January 19, 2020 at 03:09PM by OhBuggery
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Dragon has separated from Falcon 9 and its SuperDraco engines have completed their burn https://t.co/tDhogz1qQ9
https://twitter.com/SpaceX/status/1218919149079908353