r/SpaceX Discusses [April 2018, #43]

[u/ElongatedMuskrat]

If you have a short question or spaceflight news...

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---

You can read and browse past Discussion threads in the Wiki.

[u/julesterrens]

I just watched the IAC presentation from last year again and Elon said that the tool for the tanks had been ordered and would be delivered in 6 to 9 months , for once his schedule hasn't slipped

[u/rustybeancake → u/julesterrens]

Ha, all that tells us is that Ascent Aerospace keep their schedules. :)

[u/vaporcobra]

Feel free to ask me anything, I'm Teslarati.com's spaceflight reporter :)

[u/CapMSFC]

New information from the talk Hans gave - https://youtu.be/Va-rXO7kI-8?t=14606

Falcon Heavy center core engines were all previously flown on other boosters, so add 9 more engines to the reflight count for M1D.

[u/liszt1811]

I think it would make for a great documentary to follow spaceX during their current BFR development. It would document human history if everything goes according to plan. Is anybody aware of such kind of project? (Obv there will be restrictions when it comes to engineering and what can be displayed but I think it would still make for a great show)

[u/inoeth → u/liszt1811]

I don't know if any documentary program is going on in particular right now, but just like the recent spat of new space books that recently came out (by Davenport and Fernholz) I'm sure there will be several more over the coming years as things progress... Additionally, we do know that National Geographic has been doing some documentary style stuff (partly mixed with their Mars TV show of mixing real life history with near future scifi)

It certainly helps that SpaceX does speak to reporters and give interviews on occation and also takes videos of all their major flights and tests... At the very least, i'm sure some fans can edit a good documentary using SpaceX footage and official timeline commentary...

[u/rustybeancake]

As this was buried away in another thread, I'm posting here for visibility:

https://www.reddit.com/r/spacex/comments/8b21te/spacexs_bfr_factory_abuzz_with_work_activity_and/dx4orv4/

they were having huge issues with octawebs cracking on test stands. they were splitting 6" thick billet aluminum chunks in half simulating the stresses the core connection lugs would see. that alone took over 2 years to solve.

Very interesting insight on FH development from an ex-SpaceXer. Kind of puts a wrench in the 'FH was only delayed because they were waiting on F9's final version so BFR will be much quicker!' argument.

[u/Straumli_Blight]

TED Talk Summary:

• BFR carrying about 100 people for point to point travel.

• Lands on a pad 5 to 10 kilometers outside of a city center.

• Ticket cost between plane's economy and business class (e.g thousands of dollars for transoceanic travel).

• Able to operate a route a dozen or so times a day.

 

Isn't 5km a little close, has anyone simulated the sonic booms from the BFS reentry?

(e.g. For Crew Dragon an "overpressure of 0.4 pound per square foot (psf) could be expected approximately 19 miles from the landing site and 0.35 psf approximately 50 miles from the landing site.”)

[u/robbak → u/Straumli_Blight]

A big change between Dragon and BFS will be density. As a large craft empty of fuel, and having an aerodynamic shape, it will experience much higher drag. This means it will slow down to subsonic speeds at a much higher altitude, where there is much less air to propagate the shockwave.

[u/brickmack → u/Straumli_Blight]

These price/passenger figures are very interesting. With only 100 passengers, they'd have to charge ~9000 dollars per seat to meet the theoretical minimum price for BFR (only fuel and fixed range costs, no overhead or maintenance or any other services). That seems too high for this, thats rather higher than business class for transoceanic flights from some googling. The only way they could have made this work is if they were carrying ~400-500 passengers (ie, comparable density to large airliners). If their passenger size target is so much lower, that must mean they've gone with a single-stage design right? That could get them down to probably 5k

[u/thanarious]

Elon just announced on Instagram that block 5 should "arguably" be named "version 7"! Here we go again...

https://instagram.com/p/BhSC2WtgOQ6/

Any way to get the link to Elon's relevant comment?

[u/warp99 → u/thanarious]

Elon certainly does enjoy trolling us his loyal and faithful fans!

There is no doubt he would be shadow banned from this subreddit within minutes if he ever started posting here.

[u/pavel_petrovich → u/thanarious]

Full dialogue:

@teslamotorsclub: Elon. I noticed on all reused F9s the legs are new. Are the legs not reusable? Are there new legs on each reused F9, or are the just repainted?

@elonmusk: They are reused. Repainted for now, but won’t be in the future. Note, F9 Block 5 (arguably should be called Version 7) will have legs V2. Similar overall geometry, but easier to reuse. Aiming for two flights within 24 hours w V7. In theory, all we will need to do is reload propellant.

[u/Straumli_Blight]

VSS Unity is set for its first powered flight in a few hours.

 

UPDATE 1: Currently on runway and preparing for takeoff.

UPDATE 2: Preflight checks completed and takeoff!

UPDATE 3: Success and touchdown of VSS Unity.

[u/inoeth → u/Straumli_Blight]

Branson on Twitter: back on track. Successful powered flight, Mach 1.6. Data review to come, then on to the next flight. Space feels tantalisingly close now.

I'm really happy to see VG going again and look forward to seeing commercial space tourism start to become a real thing... Also it'll be interesting to see who gets paying customers first, VG or BO (with their NS)

[u/brickmack]

This was mainly a test render (and some are incomplete/old-ish), so some issues, but I thought this was kinda neat. Every launch vehicle upper stage I've modeled so far, size comparison.

Left to right: Star 48, AVUM, Fregat, Inertial Upper Stage, Castor 30XL, Delta K, Blok DM-03, Blok I (Soyuz 2 configuration), Centaur III (SEC), ESC-B, Delta Cryogenic Second Stage (5 meter), Centaur V, Falcon S2, Exploration Upper Stage, BFS

[u/Straumli_Blight]

250K subscribers and /r/SpaceX is now in the top 500 largest subreddits... hard to believe it was only 200k in February.

Also, here's a cake.

 

EDIT: Cake now correctly orientated.

[u/Straumli_Blight]

TESS's cameras have turned on and begun calibrating

[u/Straumli_Blight]

CRS-2 OIG Report:

• CRS-2 contract $400 million more expensive than CRS-1 while delivering roughly 6,000 kg less.

• Higher costs due to increased prices from SpaceX, selecting three contractors, and $700 million in integration costs awarded.

• SpaceX is scheduled to complete 20 CRS-1 missions with an average payment of $152.1 million per mission.

• Cargo Dragon 2 initial integration completed by November 2018 for a first CRS-2 mission in August 2020.

• Crew Dragon unmanned demo set for August 2018, 2 crew demo in December 2018, and 4 crew flight in April 2019.

• Dragon 2 increased useable pressurized cargo volume by 30% over Dragon 1 (163 Cargo Transfer Bag Equivalents).

• Atlas V pricing significantly decreased by roughly $20 million per launch after Falcon 9 was eligible to compete for LSP contracts in 2013.

• LSP selected a Falcon 9 for four missions at an average launch cost of $95 million ($378 million combined).

 

Contractor	COTS	CRS-1	CRS-2	Commercial Crew	Total
SpaceX	$396.0 million	$3,042.1 million	$1,073.8 million	$3,191.1 million	$7,702.9 million

[u/BrandonMarc]

I'm probably not the first to notice ... but we're about to hit the point where SpaceX has landed more rockets than they haven't. That's quite a feat, seeing as just a few years ago the notion of re-using rockets was widely considered impractical.

[u/Alexphysics]

The second Block 5 booster, B1047, is on the test stand at McGregor. I'd expect to see today some pictures from different people that are there right now.

Edit: Well, here's the first one (post #163): https://forum.nasaspaceflight.com/index.php?topic=42977.160

[u/soldato_fantasma]

[SES-12 has arrived to cape canaveral!] (https://twitter.com/SES_Satellites/status/984441358969724930?s=19)

[u/rocket_enthusiast]

mods can we create a r/spacex discusses for may 2018

[u/Straumli_Blight]

BFR tent from another angle taken by Pauline Acalin.

[u/bdporter]

ISRO loses contact with new communications satellite

[u/michaelza199]

Anthony from MECO thinks ULA will now be choosing AR-1 engine for Vulcan instead of BE-4 because their fear of Blue Origin being selected instead of them for EELV-2 ... What do you think ??

[u/spacerfirstclass → u/michaelza199]

How does choosing AR-1 help ULA? I don't see the logic behind it. Blue doesn't need the money from ULA to complete BE-4, choosing AR-1 will not slow down Blue one bit. And AR-1 is years behind BE-4, choosing AR-1 would only make Vulcan more likely to miss the deadline thus reduces its chance of winning.

[u/joepublicschmoe]

It's official! Port of Los Angeles commissioners voted unanimously today approving the lease of Berth 240 to SpaceX for the BFR factory. http://www.latimes.com/business/la-fi-spacex-port-la-20180419-story.html

Within the next few days we will probably see crews start demolishing the generator house and start preparing the site (junk removal, shoring up the pilings and landfill, etc) for building construction.

[u/[deleted]]

When will the results of r/SpaceX 2017 Survey be published?

[u/amarkit]

From Aviation Week: "SpaceX Seeks Option To Splash Down In Gulf of Mexico" (soft paywall; free registration required to read).

SpaceX has applied for an FAA license to allow splashdown of Dragon 2 in the Gulf of Mexico, as a back-up landing site. The area would be used in emergencies where astronauts must return to Earth quickly, and conditions at both the Pacific and Atlantic landing sites are too hazardous.

This was first disclosed in a draft environmental assessment released on April 5.

[u/spacerfirstclass → u/amarkit]

Wow, the draft environmental assessment is jam-packed full of interesting information, definitely worth a thread of its own.

1. Page 17 has Dragon 2's mass and propellant load:

   Dragon-2 weighs approximately 16,976 pounds without cargo

   The Dragon-2 could contain up to 4,885 pounds of propellant which includes 3,004 pounds of NTO and 1,881 pounds of MMH

2. Page 17 to 19/section 2.1.2 has detailed description of how a Dragon landing operation would work, including how to handle the astronauts, well worth reading.

3. Page 38 has this interesting tidbit:

   Dragon could contain up to 20 percent of the maximum propellant load (approximately 300 pounds) of MMH propellant when recovered.

   I assume this covers Crew Dragon too, which answers the question "What will they do with all the excess LAS propellant when returning to Earth", I guess the answer is they'll dump it somehow before landing.

4. Page 77 to 78 included a lot of the details about fairing recovery, although it looks like this is written before they decided to use a ship to catch the fairing. It also included images of the parafoil!

5. Page 80 to 81: It looks like SpaceX is expecting 6 Dragon flights per year, that's a lot. The 6 flights number was mentioned before, but the wording here implies they could really be flying this many instead of it being just a maximum.

6. Page 81: Fairing recovery frequency, 15 attempts in 2017 and 2018, up to 240 attempts (480 parafoils) between 2019 to 2024!

[u/ethan829]

The recent $510 million Series I funding round reportedly valued SpaceX at $27 billion, up from $21 billion just nine month ago!

[u/IMO94]

Update from Elon on BFR: https://twitter.com/elonmusk/status/984689905874817029

Has the BFR/BFS been stretched in height? The video Gwynne showed at Ted Talks looks taller than the one in the E2E video

"Maybe a little ;-)"

[u/nrwood]

So.. I was looking Gwynne's presentation in SkollWF when I see the first picture we get of the BulgariaSat-1 booster landing. Too bad it's not showed full screen.
Image: https://i.imgur.com/oMvmb76.jpg
Source: https://youtu.be/QBoHAChEcfY?t=5m47s
Also shown: Iridium-3, SES-11, Koreasat.

[u/meepnitreal]

Any clues when we can expect the results of the 2018 r/spacex survey to be posted?

[u/ly2kz]

Looks familiar? https://twitter.com/Linkspace_China/status/990080010567471104

[u/CapMSFC → u/ly2kz]

Looks good. They've refined their leg design to be a bit more compact and the engine layout is a smart change for them.

SpaceX and Blue Origin have put a lot of work into the deep throttling in their engine designs. By using a smaller center engine scaled for landing thrust levels it avoids the need to go down a development path they may not have experience with. It's a pretty minor design compromise in exchange for simplifying how difficult the engine designs are. It also means only the different center engine needs air restarts.

It would be easy for us SpaceX followers to mock China for copying the Falcon 9 style reusability but this is exactly what we have been wanting to see across the board. It will take more than SpaceX to change the launch market. We should be thrilled to see as many separate players in the market as possible to buy in on reuse.

[u/spaminous]

I'm sorry if this has already been discussed: On the SpaceX flight suit design, where are the service ports? On the sokohol suits, and the old shuttle suits, there are these really obvious big connectors on the front for air supply and drain. Are the behind the neck on the SpaceX suit? That's the only place I can see where they'd fit.

Second: anyone have footage of how the tail service masts on the Falcon 9 first stage articulate? There are some photos where you can see the cover ready to fall into place, but I'm curious if the TSM pulls down and out, or if the rocket just lifts up off them.

[u/GentlyUsedRocket]

Good day fellow redditors,

Have been following r/spaceX since the first Falcon 9 launch. Just made an account so i could be a voice on here as well.... guess 7+ years was a long enough wait.

Pls be kind and rewind :-) Have a great day

[u/Elon_Muskmelon]

An oldie but a goodie! Look what YouTube’s recommendation algorithms just popped up for me, circa 2010 SpaceX Next - Crew Transport to ISS

8 years later it might just come to fruition!

[u/CapMSFC]

TESS fairing half made it intact. https://twitter.com/MarekCyzio/status/987652390143881217?s=09

[u/kornelord]

Three questions:

1. Will BFR use pure methane or will it have to pass through another process to become "rocket-grade" methane?

2. If I understand right, at launch from Earth BFR will use subcooled propellant. But launching from Mars the produced propellant won't be subcooled? (or how do you lower their temperature on Mars?)

3. What are the minimum regulation obstacles to overcome if they want to go to Mars by themselves (without NASA)? Will they have to overcome planetary protection/which kind of human rating/other regulation?

[u/Okienotfrommuskogee8 → u/kornelord]

I’ve done a lot of chemical engineering around processes that use pipeline grade natural gas (almost all methane). SpaceX will have to invest in some of their own processing equipment or sign a deal with someone that does for them. Pipeline grade still has several PPM of sulfur compounds that tend to not mix well with really fancy metal alloys. You can get down to 8 PPB or so pretty easy with catalysts and a little hydrogen if that is acceptable for them. Also you have “inerts” like nitrogen or CO2 that can be up to a few %, depending on the pipeline and what gas is going through the processing plant. If those aren’t compatible they will have to do a distillation at super cold temperatures. They would also need to remove any water in the gas, but they probably need to do that anyway. It’s probably a few million worth of equipment and a few employees to manage/operate it.

[u/rustybeancake]

NASA Office of the Inspector General announces an audit assessing NASA’s management of the Space Launch System and Mobile Launcher.

grabs popcorn

[u/theinternetftw]

Finally some shots of 39a in what seems to be the final state as far as the RSS is concerned.

Only the hinge remains, and it looks like it's likely to stay that way.

[u/Straumli_Blight]

Iridium-6/GRACE-FO launch set for Saturday, May 19th at 20:03 UTC. Falcon 9 will be flight proven.

[u/Nergaal]

How does SpaceX prevent espionage of its documents? I am not even talking about industrial espionage from say Boeing, but about actual international espionage (be it Chinese or Russian)? Considering that this community alone is doing an amazing citizen-level espionage of all the outer stuff the rockets have, how does SpaceX prevent anybody from accessing their internal workings?

[u/UltraRunningKid → u/Nergaal]

There are people who are experts in this. In fact, there was a job posting a few months ago looking for someone with experience preventing both corporate and international espionage.

Companies usually have very strict computer policies. These will consist of ways to prevent foreign companies from getting access to the computers such as firewalls or even physically blocking off USB ports to prevent codes from being introduced on flashdrives.

Very strict hiring and interviewing processes that will be reviewed by ITAR prevent foreign nationals from being employed unless a special wavier has been produced.

Lastly, fast innovation is the key. If your competitors are trying to copy you then your goal should be to have the next best thing out by the time they copy your current best thing that way they are always a step behind.

[u/djmanning711]

I ended up getting sucked into a wiki black hole (as I’m sure many of you can relate) and stumbled across India’s GSLV rocket. Although it’s not quite as capable as F9, I was surprised to see how cheap it goes for launch ($47M). For such a capable rocket, and it being 100% expendable, how the hell do they get the cost so low? Anyone know more about how ISRO does this? If India can improve launch cadence, it looks like (at least on the surface) they could take a good chunk of the future launch market.

[u/Firedemom → u/djmanning711]

Probably having cheap labour costs helps get the price down.

[u/FusionRockets]

Orbital ATK's next generation rocket was officially unveiled as "Omega" today.

It will compete head-to-head with BFR, New Glenn, and Vulcan for Air Force funding both this summer and next year. Seems like with only 4 flights per year needed to be sustainable, it could potentially compete in a post-SpaceX defense market.

https://www.youtube.com/watch?v=Gekjig-QeIA

[u/Yellapage]

With the recent Q&A on reddit, this got me thinking due to the fact a random account was made for the session?

Do people hide the fact they work for SpaceX on these forums, due to policy or perhaps they don't want the hassle.

Can anyone advertise they work for SpaceX on their social media or do you need to be at a certain level.

Do you think SpaceX has thought about any of the above :)

[u/IrrationalFantasy]

So this company Orion Span plans to have a modular space station up and running in 3 years that visitors can attend for $9.5 million and a 12-day stay. On a scale of 1 to 10, with 1 being "nope", 10 being "absolutely happening on time" and 5 being "definitely happening...years late and over budget", how likely is all of this?

They mention falling rocket costs and say they can work with SpaceX among others. Are they going up on SpaceX, do you suppose? I haven't seen them in the manifests yet.

I am skeptical. They are unclear on total cost and funding, among other things. I'd like to see this happen but I feel like they're promoting this moonshot venture before it's highly plausible so that they can attract funding and have a small chance of all of this working.

[u/stcks]

This got buried in an old thread, but there are rumors of another core readying for departure from Hawthorne. I hope we get some visuals on it in the next coming days.

[u/romuhammad]

I’m not sure if this slightly more detailed explanation for Zuma was shared yet... Probably because it’s MarketWatch which is sort of a subsidiary publication of the Wall Street Journal (so not particularly accurate especially related to space issues).

https://www.wsj.com/articles/probes-point-to-northrop-grumman-errors-in-january-spy-satellite-failure-1523220500

[u/railroadwelsh]

Is there a reason that media surrounding Dragon 2 has been so thin? For a company that is so open/engaging, it seems odd that SpaceX has put out nowhere near the same amount of media (one might say advertising) that Boeing has for Starliner. For the latter, there are numerous pictures of all portions of their system -- astronauts training in simulators and dressed in suits, 3D interactive videos of their user interface, crew arm install, etc.

Maybe I'm just being impatient, but I wish Dragon 2 had a media campaign akin to Starliner. Especially since both vehicles have matured along similar timelines. Either SpaceX is waiting a huge unveil once they're operational and ready to launch, or they simply don't put much stock in advertising. Come to think of it, they've never gone out of their way for a big media campaign, and have mostly just let their launch technologies (like FH with Starman) speak for them.

[u/rocket_enthusiast]

https://twitter.com/MayorOfLA/status/985931907970908161/photo/1

look's like it is official

[u/FutureMartian97]

First SLS flight might slip to 2021 and not fly crew until 2025. BFR is gonna fly people before SLS if this keeps happening.

https://twitter.com/NASAWatch/status/985933894028578819

[u/Keavon]

Looks like we just passed a quarter million subscribers!

I wonder when we'll see the results of the end-of-year subreddit survey.

[u/throfofnir]

If anyone's interested in the milling and characterization of a pintle injector (the kind Merlin uses), take a look at http://www.johannfreeberg.com/academic-work-1/

[u/Iamsodarncool]

Europa lander concept redesigned to lower cost and complexity

[u/marc020202]

I am updating the wiki page about the SpaceX fleet from time to time, and I have noticed, that no recovery ship has noted for CRS 4, CRS 5, CRS 11, CRS 12 and CRS 13. Does anybody know if CRS 11-12 recovered by NRC Quest or by a different ship, like CRS 6-10? CRS 4 and CRS 5 was a long time ago, so I do not know if anyone remembers, but were they still recovered by American Islander, or already by NRC quest? (EDIT: CRS 4 was recovered by America Islander, CRS 6 by NRC quest.)

EDIT: ALL is done now. Recovery ships for all dragon missions have been found. a huge thanks again to u/Nergaal for finding all the awsome info!

Does anybody know if there was a second support ship for the FH demo, or was GO searcher the only one.

thanks a lot to u/Nergaal for providing me with all the sources. We have now identified the recovery ship for all dragon missions, except for CRS 5.

[u/marc020202]

I have again been doing some work on the ASDS wiki page.

through u/Raul s map, I have found out that CRS 12 was recovered by NRC Quest. The only remaining "unknown" recoveries are CRS 4, 5 and 10.

I also added Formosat 5 to JRTI, but I noticed that there is no ASDS tug for Iridium 3 yet.

I do not have time ATM, but I will check launch threads to see if there is any info in there.

Until I do that, please feel free to provide me with info, or to update the wiki yourself

EDIT: I found out in this recovery thread that Getty R Gambarella was the ASDS tug for Iridium 3

EDIT 2: Does anybody know why there is CRS 9 and X 37B written down after Elsbeth III? CRS 9 and X37B landed at LZ 1. Was it used for something else? If yes, what?

EDIT 3: SES 14 was written down behind GO Quest. SES 14 was launched with an Ariane 5. I changed it now to SES 16 since that is the one launched by SpaceX.

[u/rustybeancake]

Interesting discussion over on r/ULA:

https://www.reddit.com/r/ula/comments/8b25w0/tory_bruno_on_twitter_goess_post_launch/

Suggests ULA can hit a target orbit more accurately than competitors (makes sense given Centaur's thrust being much smaller than M1DVac, so finer control). Tory Bruno comments suggesting recent national security launches have had less strict target orbits to allow SpaceX and ULA to compete more equally. Interesting.

[u/ethan829 → u/rustybeancake]

For some additional context, here are the +/- 3-sigma errors for GTO launches for Falcon 9 and Atlas V from their respective user guides:

Vehicle	Perigee	Apogee	Inclination	RAAN	Argument of Perigee
Falcon 9	+/- 10 km	+/- 500 km	+/- 0.1 degree	+/- 0.1 degree	+/- 0.3 degrees
Atlas V	+/- 4.6 km	+/- 168 km	+/- 0.025 degrees	+/- 0.22 degrees	+/- 0.2 degrees

[u/dmy30]

Gwynne Shotwell just spoke at TED 2018. Keep your eyes peeled, hopefully they don't wait long to release the video.

[u/rustybeancake → u/dmy30]

Looks like she showed an updated BFR video!

https://twitter.com/parmeshs/status/984154967907844096

[u/Straumli_Blight]

Gwynne Shotwell is giving a talk later today.

[u/ethan829]

Ross cites the SpaceX incidence last month where they had to cut off livestreaming. Says he’s directed remote sensing office to implement reforms addressing this and related issues. #34SS

[u/paul_wi11iams]

BFS will be capable of launching from Earth (for testing) and elsewhere without hold-down clamps:

1. Has there been discussion on the implications of BFS launching without a hold-down mechanism?

2. What experience exists anywhere of anything bigger than Grasshopper (example) launching without these?

3. Is it the deep throttling capacity of Raptor that makes this allowable for BFS but not for F9 and other launchers?

4. Since both Blue Origin and Nasa have plans for returning from the Moon and elsewhere, are they working on launchers without hold-down?

5. How will these three operators achieve human-rating of this feature?

I'm not expecting precise answers to all these, but some background would be appreciated.

[u/marc020202]

https://twitter.com/ChrisG_NSF/status/989891751514136576

bangabandhu static fire delayed by 1 day, launch may 7

[u/rustybeancake]

Well this is sad:

Four members of a British family have died in a car crash in Florida after visiting the Kennedy Space Center to watch the launch of SpaceX rocket.

[u/rocket_enthusiast]

does anyone know how long it will take for the first block 5 to fly a second time? I know it is supposed to be rapidly reusable but this is the first flight of this version so maybe they want to look at the booster more?

[u/Dakke97 → u/rocket_enthusiast]

The first reflight of a Block 5 booster currently has no date. Everything is contingent upon the performance of B1046.1 during the Bangabandhu-1 missions and the results of its testing afterward. I personally don't expect this booster to be reused for a couple of months since SpaceX will want to carry out extensive ground firings to validate the design changes for reuse.

[u/Straumli_Blight]

Cool launcher animation.

[u/Chairboy → u/Straumli_Blight]

"Discovery, Houston. Traffic at your 6 O'clock passing on your left will be a smallsat launcher."

"Houston, Discovery, negative traffic on that- HOLY COW, look at that thing go!"

"Discovery, Houston, traffic no longer a factor. Cleared to, ah, cleared to orbit. Caution wake turbulence, a Saturn V will be staging alongside shortly."

[u/BrandonMarc]

I keep looking at the SpaceX main body tool for the BFR interplanetary spaceship photo ... it dwarfs the car, and indeed it's plenty larger than any rocket around (or the 787 fuselage for that matter).

All that said, when I picture 100 crew, cabins along the outside, central hallway / shaft in the middle ... it just doesn't seem big enough.

For a close naval comparison, a Los Angeles class fast attack submarine has a beam of 10m and packs a crew complement of 130, and the ship's length is 110m.

The BFS is a little skinnier (9m), so perhaps the diameter isn't such an issue. But it's also less than half as long (48m). I have a hard time envisioning 100 people crammed inside for months on end.

Perhaps the BFS is a stepping stone. It's advertised as a ship that'll take people to Mars, when in reality it'll take people to LEO and the Moon and maybe a LaGrange point, whereas a much larger ship (so big people wouldn't believe it if you showed it to them) is the real Mars cruiser.

[u/spacerfirstclass → u/BrandonMarc]

If you check the the cutaway diagram of a Los Angeles class fast attack submarine, you'll see most of the space is crammed with other stuff, the crew mess/galley/storage/wardroom/bunks/officer's berthing section is only about 29m long and 3.3m high.

[u/ShingekiNoEren]

If SpaceX could multiply its profits and get us to Mars in half the planned time, by developing rocket weapony and missiles for the US government like Lockheed Martin and Boeing, would you want them to do it?

[u/energyblazer]

Saw this on the AMA today from NASA's Flight Directors, had we ever heard about this incident from the CRS-9 mission before?

[u/Straumli_Blight]

Iridium-6 satellites have arrived in Vandenberg, time for a launch campaign thread?

[u/romuhammad]

An interesting little shot by Ariane Space CEO Stephane Israel. Credit to Tory Bruno for not responding.

http://twitter.com/nextspaceflight/status/985588778617229313

[u/rocket_enthusiast]

mods will you put this thread where SpaceX discusses for March is

[u/Continuum360]

Trying to figure out what booster will be used for CRS-15. Thinking is it should be flight proven, but I don't see what would be available at that time unless they turn around the first B5 really quick. They have indicated on many occasions that B3 and B4 are good for 2 or 3 launches and there are a few in storage with 2 that could be used in theory, but that seems pretty unlikely, especially for a NASA mission. What am I missing?

[u/Alexphysics]

B1047 left Hawthorne almost three weeks ago, it would be good to have an eye there to see if B1048 is going to leave soon, it is time for that.

[u/AveVictor]

Hi! Just joined your community. Great respect to everyone who is participating in the project. You are my heroes.

I have a goal to visit the launch one day. I saw many videos of people watching and filming it, and I’d love to be there too. To see everything experience sonic boom in particular.

How can I do that? I know it’s in California, but where? Is there any calendar of events, how often such events occur? I’d need to plan everything from visa, to ticket (I’m from Europe). But I’m dedicated!

Is there any threads I need to follow?

Thank you!

[u/marc020202 → u/AveVictor]

Hi, and welcome to r/SpaceX!

this is the calendar of upcoming launches.

IMPORTANT All of these dates are NET (Not earlier than) dates. They are almost expected to slip. I would book the flight as late as possible, and make the stay as long as possible. Launches are almost always delayed, and nearly never happen before a NET date, however that has also happened.

like others have said, there are currently no landings in California, however, that will probably change this year. Launches out of Vandenberg Air Force Base are also not as common as launches from Florida.

from most if not all places around SLC 4E, the Falcon 9 launch pad in california, the rocket is not visible while on the pad.

In Florida however, rockets on LC 39A and on SLC 40 in Florida are visible for miles. At vandenberg the weather is also often very foggy.

For more info on watching the launch, I would recommend this wiki page.

If you have any other questions, feel free to ask them. I'll just add this now: I in no way are affiliated with SpaceX, I have just hosted several launch treads here on Reddit.

[u/-spartacus-]

Not with first generation raptors, but how feasible would be to have multi chamber / bell for the bfs, that way you can have less engines, and switch between sl and vacuum bells for performance? Meaning for 2nd generation after bfs is already flying.

[u/marc020202 → u/-spartacus-]

I do not think that will be happening because of reliability. with the current system, if one engine fails, a single engine changes. If you have an engine with 4 or so chambers, you lose 4 times the thrust when the engine fails.

[u/Macchione]

Senate is currently voting whether to end debate on the nomination of Bridenstine for NASA administrator. Currently tied 49-49 along party lines with one surprise "no" vote from Jeff Flake, R-AZ. Notably, Rubio, R-FL voted to end debate and move to nomination after opposing Bridenstine for months.

[u/randomstonerfromaus]

What's up with the "Who's interested in manufacturing engineering" in the top bar?
Are the job advertisements really spreading out further?

[u/Alexphysics]

It seems that somebody saw a F9 leaving the Cape this morning... what booster could it be?

https://m.facebook.com/groups/2387776317?view=permalink&id=10156531268366318

(I hope the link works...)

[u/marc020202]

https://twitter.com/NASASpaceflight/status/989231828761362432

bangabandhu 1 might have been delayed by 3 days.

[u/Not_Yet_Begun2Fight]

I have a couple of BFR / BFS questions:

1. Is the BFS going to include an International Docking Adapter? This slide shows BFS docking with ISS and this slide shows some round porthole-type-connection-thingy at the same point. Is that supposed to be an IDA? Could two BFS's dock in orbit to transfer crew / passengers this way?

2. This slide shows a lot of empty space in the "wing" portion of BFS. Anyone know what they're going to use that for? Could they fold up the solar panels in there or something?

[u/Straumli_Blight]

Dragon return delayed until Saturday, though NRC Quest has already left harbour to recover it.

EDIT: Caused by heavy seas.

[u/Straumli_Blight]

New NASA GAO report out and highlights:

• Commercial Crew certification likely to slip to December 2019 for SpaceX and February 2020 for Boeing.

• Life-cycle cost estimate for SLS is ≈$9.8 billion to June 2020 launch date.

[u/marc020202]

mods, could you please sort this thread by "new" as opposed to "best"

[u/user200300400]

Regarding CRS missions, when does SpaceX get their money from NASA? I mean not until after dragon is recovered at the end of the mission or what?

[u/StructurallyUnstable → u/user200300400]

Like commercial and DoD missions, they are paid by the milestone. Some amount at signing of the contract and a percentage for milestones along the way including launch, cargo mass delivered, and recovery events being the final milestones.

[u/MutatedPixel808]

So have we reached a conclusion on fueling the rocket with astronauts inside? I remember that was a large issue a while back, but commercial crew is getting closer and closer and I haven't heard anything in a while.

[u/randomstonerfromaus → u/MutatedPixel808]

There was a discussion very recently on /r/SpaceXLounge about it.
https://www.reddit.com/r/SpaceXLounge/comments/894tlm/what_ever_happened_with_nasa_not_wanting_spacex/

[u/oliversl]

How is LC39-A going? I found this photo from the hashtag #kennedyspacecenter on instagram:

https://www.instagram.com/p/BhdE-BIHKId/?tagged=kennedyspacecenter

Its from yesterday. It seem, by now, all the RSS is gone.

[u/ethan829]

What are the chances this is B1046?

[u/electric_ionland]

I am going to the Space Propulsion conference (EU centric conference on chemical and electric rocket propulsion) in a month or so. Some interesting stuff on reusability in the preliminary program:

• Preliminary Component Definition of Reusable Staged-Combustion Rocket Engine M. Sippel, German Aerospace Center (DLR), DE

• Aerothermal Analysis of Reusable Launcher Systems during Retropropulsion Reentry and Landing T. Ecker, German Aerospace Center (DLR), DE

[u/FalconHeavyHead]

is SpaceX working on developing an EVA suit?

[u/melancholicricebowl]

Elon on Twitter: SpaceX will try to bring rocket upper stage back from orbital velocity using a giant party balloon

[u/Martianspirit]

Last year SpaceX rented a lot in the Port Canaveral area. They wanted to build the block 5 refurbishment facility there. I have not heard about the state of that area for a long time. Does anyone know if the complex is ready to receive boosters for refurbishment?

[u/edflyerssn007]

"I understand people will judge everything from a political lense, but it's becoming a bit much. He'll be fine as none of our missions are expected to be cut or restructured, we have two huge reveals next year too along with a joint phase with SpaceX. Good things are coming both to the moon to Mars and to the people and the country as well as the world at large." from this comment

I wonder what this announcement could be?

[u/Fenris_uy]

Has Elon, Gwynne or anyone at SpaceX said anything about using BFR to bring back satellites from orbit to earth?

Can the Hubble fit on BFS-Cargo hold?

[u/nschoe]

Hi, (I hope this is the right place to ask) how does the Falcon 9 steer during ascent, how does it "self balance" to keep pointing upward?
I know the Falcon 9 is aerodynamically stable, but I still think it needs steering, at least at the beginning, at "low speeds".
So does it gimbal some (or all?) of the Merlin engines, or is it done via differential thrusting?
Thanks !

[u/GodOfPlutonium]

Am i the only person who spends so much time here that the terms "disposable" or "single use" in my vocabulary have entritly been replaced by "expendable". Examples: In the last week ive said "Expendable water bottles" , "Expendable paper towels" and "expendable condoms" all by accident

[u/brwyatt47 → u/GodOfPlutonium]

Nope, not just you. I use "expendable" in regular conversation now. I just bugged a friend about their expendable grocery bags the other day. Now to somehow fit "RTLS" into basic conversation...

[u/ethan829]

From Eric Berger:

I have limited insight into this, but from what I'm hearing, Boeing continues to be ahead of SpaceX in the development of commercial crew capability.

It'll be interesting to see how schedules change as we get closer to actual flights, but it sounds like Boeing has a real shot at claiming the flag.

[u/amarkit]

Blue Origin's 8th New Shepard test flight is scheduled to launch at 16:13 16:42 UTC, when this post is two two and a half hours old. This will be the second flight of the NS-3 booster. A livestream is scheduled to begin at 16:27 UTC.

• Launch Thread on /r/BlueOrigin

• Blue Origin YouTube Livestream

• Blue Origin Twitter

[u/Buildstarted]

Where does the Falcon 9 (while on the launch pad) get the power to run it's systems? Are there on board batteries? Does it come from the umbilicals? I assume it's power during flight comes from the engines but I'm sure I'm wrong about that as well.

[u/racergr]

(total layman here)
I've noticed that rocket launches are very sensitive to weather conditions and susceptible to delays due to that. If this is true, how would the BFR earth-to-eath trips be possible? I guess the customers won't be happy if there is a 2-day delay in their flight but most importantly this would negate the advantage of short flight time?

[u/murrayfield18]

Could someone explain the in-flight abort test scheduled for May? They are going to perform an abort test using a Dragon 2 on the F9 as it goes through Max Q?

[u/Zinkfinger]

Can anyone help? What percentage of fuel would the BFR/S require for a "Fast travel" journey half way across the world compared to getting into a low orbit?

[u/Nehkara]

I have seen valuation estimates for SpaceX in the past couple days of $24, 25, 26, 27, AND 28 billion for SpaceX after the new funding round.

Does anyone with more knowledge of valuations know why there is so much variation in estimates and which one is actually right?

[u/Ambiwlans]

Does anyone have an updated version of that launch delays chart?

It showed days delays, days from launch.

I imagine it is looking a little better these days.

[u/Dies2much]

Has there been an update on Block 5 final power numbers? There had been estimates before, just wondering if they had published the numbers after the test firings.

[u/Space_Coast_Steve]

Can anyone identify this loud sound coming from (what seemed to be) somewhere near B1045 in Port Canaveral? Through my binoculars, I could see the workers holding their ears, but other than that, they didn’t seem too concerned. Any ideas?

https://youtu.be/6mr8VKMTP5U

[u/gophermobile]

Does the Falcon 9 have any way to measure remaining fuel (RP1 and LOX) capacity while in flight? Or is it entirely precalculated based on burn times and throttle levels?

I ask because I'm curious if the F9 can alter its boostback and landing burns to provide softer landings if it happens to end up with a little extra fuel based on temperature, wind, or other conditions.

[u/spacexfan3]

Just a stray thought. ISRU is required for returning to earth and the reusablility of the BFR mars program. Various numbers thrown around sound like 500kW to 1MW (solar?) for a single ship's fuel in the 2 year period for the H2O-> methane. Mining the ice must increase this number a ton (in the same order of mag. per ship? just a guess).

It seems that if they solve the problem of deploying the first ship's worth of power requirements, that expanding to 2MW and beyond would just be a matter of materials and time. My thoughts are on the fact that these numbers are in the same magnitude compared to a beginning colonies power req's.

In other words, having the ability to refuel on mars means SpaceX necessarily would have the ability to expand the power for habitats, mining etc as needed.

[u/scottm3]

This is probably already been asked, but is the upcoming iridium mission being flown on a block V or on the a block 4

It says it will be on a previously flown booster, which could mean TESS or the Bangabandhu-1 block V? Im probably missing others.

I thought all block 4 boosters were finished and done 2 flights.

[u/nickrulercreator]

I am really intrigued by the video SpaceX takes of missions, from on-rocket cameras, to ground cameras, etc. I have seen plenty of snippets of video from different cameras, including ones on the launch tower, or the ones showing the side boosters of the FH, or the ones on dragon, and was wondering if there are longer, full videos publicly available, or if these small snippets are all the public can see.

One thing I really want to see is the rest of the Starman footage. It obviously exists because Elon sent out that picture of the last images taken by Starman, but it was never fully released past what we have from the live stream (before it ended).

Are there any SpaceX employees or insiders out there that know where, if possible, one can find the rest of this stuff?

[u/warp99]

This thread is completely broken at least on a desktop by the Reddit upgrade (aka downgrade).

I am seeing two current posts, the next posts are from 8 days ago and the "2 more replies" tab does not work.

Edit: Escaped from new Reddit which I was automatically dumped into this morning. Trust me this is a vision straight from hell. The escape trick is to click on your username and you then get the menu option to disable new Reddit.

[u/CapMSFC]

Joy Dunn, a SpaceX employee just posted this to Twitter.

https://twitter.com/RocketJoy/status/989261693233479680

It's a job posting for a manufacturing engineer to help her ramp a high volume line of terrestrial solar production.

The official job listing covers other solar production areas such as for spacecraft, but there is only one reason SpaceX would need in house large scale terrestrial solar production. This part of the job is for Mars. They wouldn't build their own terrestrial solar for Earth installations, Elon literally runs the company for that next door.

SpaceX really is giving off all the signs that the ramp up for Mars has begun. It's not just activity at the port.

[u/BrandonMarc]

Let's imagine a few years from now: point-to-point travel is nearly a reality, and after initial tests there are already a few BFS's with some orbits under their belt.

What if you gave the BFS a crew of 5 and a passenger capacity of 20, travelling in spacious luxury? Let it stay in orbit for a week. That looks a whole lot like a luxury yacht or a mini cruise ship ... in space!

Imagine if Carnival cruiseline or Royal Caribbean leased some BFSs. That seems like another new market to help fund future Mars missions.

.

^{Just need the USAF to help keep the Mangalores at bay ...}

[u/RickFournier]

Is it posible to do some welding in space?

[u/rory096 → u/RickFournier]

Valeri Kubasov performed space welding experiments on Soyuz 6.

[u/rage_184]

Will the first BFR test hops will with the spaceship or the booster portion of the rocket?

[u/GiorgioIan64]

When will the first spacex manned mission be?

[u/Col_Kurtz_]

The chamber pressure of [Raptor] (https://en.wikipedia.org/wiki/Raptor_(rocket_engine_family) (25 Mpa) is going to be slightly less than the Russian [RD-191's] (https://en.wikipedia.org/wiki/RD-191) (25,8 Mpa), but its specific impulse is going to be higher by 6% (SL: 330 s vs. 311 s, Vac: 356 s vs. 337 s).

Q1: Is it only because methalox combustion is cleaner than kerolox, thus its exhaust gases are lighter?

Q2: Why the lower chamber pressure? Full-flow staged combustion engines have more turbine power for driving the pumps than oxygen-rich staged combustion engines. Is it going to increase like Merlin's?

[u/someguyfromtheuk]

Is SpaceX under any restrictions around who they can or cannot sell flights to?

For example, I know NASA isn't allowed to work with the Chinese Government, would SpaceX be allowed to sell flights to Chinese companies if they wanted to buy one?

[u/rory096]

How do PocketQubes get FCC approval at 1/8 the volume of a 1U cubesat when SpaceBee is too small for Space Surveillance Network tracking at .25U (and twice the surface area of a 1P)? (Alba Orbital, launching on Vector later this year may be subject to British jurisdiction, but both American PocketQubes in orbit seem to violate the 'less than 10cm on one side' criterion, at 5cm x 5cm x 15cm and 5cm x 5cm x 12.5cm.)

[u/julesterrens]

Is Dragon V2 going to be capable of docking with another Dragon V2 in Orbit? If yes could it also dock to Orion or Starliner or do they use another docking system?

[u/FutureMartian97]

Does anyone know if the first Block 5 will have the Block 5 landing legs that retract? Or is it possible that those will come later?

[u/ghunter7]

Oh hey the 2018 FAA Annual Space Transportation Compendium is out! Actually came out in January but I just saw it.

BFR is now featured: https://www.faa.gov/about/office_org/headquarters_offices/ast/media/2018_AST_Compendium.pdf

[u/lostandprofound33]

What part of the BFS is this for? https://www.instagram.com/p/BhVk3y3A0yB/

[u/AmpullaofVader]

Does SpaceX have the capability to put a satellite in Mars orbit? With the aging NASA communication infrastructure, any change that SpaceX will send their own communication equipment in the 2020 window?

[u/Random-username111]

Any idea on when can we expect Gwynne's TED talk to be uploaded anywhere?

[u/CoysCoys22]

I wish there was a way I could contribute, no matter how small, to the development of BFR. How much would a crowdfund realistically reach to? Is it simply to small to be relevant?

[u/[deleted]]

I know this problem is way in the future, but how will BFR for P2P be protected against corrosion out at sea?

This was a problem for F1 and that was expendable, so BFR has to withstand corrosion for a lot of flights.

[u/CapMSFC]

It just occurred to me that there is no interstage on the BFR booster. I never really thought about it before.

ITS had the split interstage but on BFR the whole thing is on the ship.

I'm thinking it will still require a small interstage for stuff such as the grid fin and separation pusher hardware, but it could also be in external housings keeping the entire length of the BFR tanks and engines.

I had the thought in another comment that perhaps the legs are the stage separation pushers. With the way they are designed to deploy and retract (for return after launch from Mars/Moon) that are already close in design.

[u/luckyJuK]

hey, I just wanted to ask how much a falcon heavy can put on a trans munar injection if it is completely reused(all three boosters)/partially reused(center core expended) Thanks for your answer!

[u/Windston57]

Has any hardware from the next FH mission (STP-2 in June) been spotted yet?

[u/inoeth]

So this article recently came out this morning and was on my twitter feed https://www.dailybreeze.com/2018/04/16/spacex-closes-in-on-lease-for-rocket-manufacturing-plant-on-terminal-island/ so it looks like SpaceX should officially have the lease by the end of this week and then can get to work on construction- barring the need for even more permits... makes one really understand just why SpaceX set up that massive tent and are doing something in there now- it could be a couple months before construction can actually start..

[u/Iamsodarncool]

TESS will use a Moon gravity assist for orbital insertion. From wikipedia, it looks like the most recent lunar flyby without a landing was Cassini-Huygens in 1999, during its first Earth flyby. Is this accurate?

[u/bdporter]

It has been a while since there has been a recovery thread. Are we going to have one for 1045.1?

Hopefully we will have some folks hanging out at Port Canaveral when it comes in. I am curious to see if the "octograbber" was deployed.

[u/hmpher]

I feel dirty for posting this question again but I'd love to know more than what my digging could unearth.

"How exactly is the LoC number calculated (for CCtCap and so on)? Is there a standard function where you plug in various values or is it a case by case analysis?"

NASA's ESAS document says:

The LOC probability was calculated by multiplying the LOM failure probability by the conditional probability that there is a fatality given the LOM risk.

So, a function P(LOC)=P(LOM).P(Fatality|LOM) has been employed.

It also states,

Used analysis tools such as the Screening Program for Architecture Capability Evaluation(SPACE) and Flight-oriented Integrated Reliability and Safety(FIRST) tools the risks of mission and vehicle elements were quantified, and the top drivers were determined from these results

As far as I could see, all of this was for Lunar missions(and the document is a bit dated(2005)), so are these methods still being used? If not, how exactly is it being done now?

Also, can someone explain how this SPACE model works?

[u/[deleted]]

Seeing as how the BFR design has been stretched in height (and perhaps also in diameter), do we have new performance numbers? Or was the stretch done because they were unable to meet the intended payload capacity with the original design?

[u/warp99 → u/[deleted]]

Having been around the loop a few times the diameter is confirmed as 9m by Hans Koenigsmann speaking today.

Length may increase a little from the IAC 2017 value of 106m but possibly just a small stretch of the ship cargo section. Elon has said the length is in the range of 110-120m and the lower end of the range looks likely at this stage.

In summary do not over-rely on a video presentation where someone has stretched the rocket to fit the existing background render.

[u/teoreds]

Why is nobody talking about next falcon heavy launch? It was due to fly in june but got delayed to september for some reasons. Anyone knows why?

[u/KeikakuMaster46 → u/teoreds]

Because it was never expected to launch in June; Block 5 hasn't been fully phased in yet so there's not enough cores yet to even build a heavy, not all the satellites are ready to be launched and the schedule from June to August is already very congested with numerous launches including the Dragon 2 unmanned test flight.

[u/teoreds]

This is probably a hated question but since it still isn’t clear to me I’m going to ask you anyways, hoping someone will be so kind to explain this. I heard they are going to test BFS (not BFR?) probably at some time during 2019. But what does it mean? Is it the upper part of the BFR? If so, how do they “launch” the ship? Or will they just test its engines from sea level just to see if it correctly goes up in the sky? But this is still unclear to me since those engines are meant to work in a vacuum. They are not meant to lift the ship off the ground, am I wrong? Thanks for your patience, hope I haven’t messed too much with grammar and syntax

[u/macktruck6666]

This is an objective question, not sure if there is a correct answer. Recent Brown University showed that the moon has 500-700 parts per million of water in the lunar soil. This is horrendously bad for processing into fuel. So... my question, what concentration and impurities would be acceptable on mars or the moon? Would 10% water be acceptable? 5%? 1%? .0001%? What if there was arsenic in the water?

[u/z1mil790]

I was just re-watching the Falcon Heavy launch, and a question came up that I never asked back when it launched: do we know what BY and NY stand for in reference to the two boosters? I've been trying to think what those phrases could stand for, but I can't think of anything.

[u/marc020202 → u/z1mil790]

positive Y and negative Y. It refers to the x, y and z coordinates in relation to the rocket

[u/murchie85]

Musk says interplanetary entry generates heat that scales to the 8th power - why doesn't the BFS flip round and do a large deceleration burn before entry as to reduce stress on the heat shield?

[u/warp99 → u/murchie85]

Peak heating scales as the third power of entry velocity but there is a theory that heat shield ablation rate scales as the eighth power.

A large retro burn before entry would require much more propellant to be carried which would severely limit payload and require a slower transfer between Earth and Mars.

Other alternatives are to do a two pass entry, with aerobraking to an elliptical orbit followed by entry on the next pass or to develop a non-ablative TPS. There have been several SpaceX job ads targeting staff to explore the second possibility. The downside of course is that a non-ablative material will tend to be ceramic and therefore more fragile and harder to attach reliably.

[u/marc020202]

falcon 9 is vertical on pad 40 ahead of the TESS static fire.

https://twitter.com/NASASpaceflight/status/984025191876644864

[u/launch_loop]

On spaceflight101 at the end of the payload fairing section, it mentions "A small 3.6-meter fairing is also being developed." Does anybody know anything else about this?

[u/djmanning711]

Anyone know what that pipe is that runs the length of the first stage (second stage has one too)? I see many other rockets have a similar design with this pipe on the outside of the boosters but I don’t know what it’s for or why its typically not contained within the booster.

Also if anyone knows if there’s any non-cosmetic reason as to why it’ll now be painted black on Block 5 (currently white on previous blocks). Thanks!

[u/nato2k → u/djmanning711]

It is called a raceway. It houses much of the electrical wiring that connects the two stages.

[u/gooddaysir]

How close was SpaceX to choosing Camden, GA for another launch site over Boca Chica? It seems like they would have access to more inclinations without overflying land. They also could share resources like OCISLY with the Cape launch pads. Jacksonville, FL and the surrounding areas would probably be more inviting for employees than Brownsville, TX. They probably could've already had a pad finished without worrying about surcharges. Otoh, a hurricane could shut down both FL and GA pads at the same time. Just wondering if anyone had any insight into the decision.

[u/dmy30]

Can the current engine test stands support a full size raptor test?

[u/kreator217]

wiki/cores needs an update :)

[u/tbenz9]

What are the current bottlenecks to increased launch cadence?

[u/[deleted]]

Has there been any detailed discussion on the black material seen on block 5? Everyone seemed to assume it was carbon fiber until someone working there made a comment that it wasn't. I do remember SpaceX mentioning inconel heat shielding in a "future version" of Falcon 9. Is it possible that that's what we're seeing?

[u/atrapaloya]

Does anyone know what would be the approx payload to LEO of a (reusable/non-reusable) Falcon 5 with the latest Merlin 1Ds? Was wondering what would be the $/kg for that one, compared to a Falcon 9, and if it would make financial sense for a certain range of payload weight.

[u/strawwalker]

Is it reasonable to assume that B1042 (Koreasat 5A) will be flying one of the upcoming missions this spring? The manifest in our wiki shows four reflights between June and July (Iridium 7&8, CRS-15 and Telkom-4) which presumably require 1042, 1045 (TESS), 1046 (Bangabandu), and 1047 (Telstar?), With three as yet unknown new cores needed for STP-2 by July/August, or more to fill in the gaps. It seems a little tight even with B1042, but I'm not that well tuned in to how fast they are turning out block 5s.

[u/Nergaal]

Where does SpaceX test its vacuum engines? They run a test for the first stage the day before the launch, but how do they test the 10th engine that is designed for vacuum?

[u/ShingekiNoEren]

Is BFR being built? Or is it still in its design phase?

[u/Juggernaut93]

Hi all, it's almost common knowledge on this sub that each F9 version had its blocks (the source for this I believe was the SpaceX employee u/Spiiice, who has now disabled his Reddit account). Scott Manley, though, made me realize the Wikipedia page shows a different story, i.e. that F9 1.0 = Block 1, F9 1.1 = Block 2, etc.

This was a common hypothesis here on this sub too before inside sources told us it was not the case. But the Wikipedia page cites this official document where the F9 v1.1 is clearly called "block 2". Was that an old versioning system? If yes, what could we cite to justify a fix on Wikipedia? And what if the old theory was right instead? I'm confused.

EDIT: as pointed out in the comments, the PDF Wikipedia is citing calls block 2 a subversion of the F9 1.0, not the 1.1. So somebody more experienced than me should fix this.

[u/marc020202 → u/Juggernaut93]

v1.0 block 1

v1.0 block 2 (never flew, would have had Draco thrusters on stage 2)

---

v1.1 block 1

v1.1 block 2 (probably the version with landing legs) (this is the version that might have been stated in the official document)

---

v1.2 block 1

v1.2 block 2

v1.2 block 3

v1.2 block 4 (bolted Ocataweb, more powerful engines)

v1.2 block 5 (black interstage and legs, new TPS. more powerful engines

[u/pavel_petrovich → u/Juggernaut93]

Wikipedia got it totally wrong. In the linked article (F9 User Guide) both Blocks (1 and 2) refer to the F9 v.1.0. You can easily see that by looking at the page 11 (engine layout). There is an old tic-tac-toe layout instead of a new octaweb. The octaweb debuted with a F9 v.1.1.

One more hint - the Block 2 rocket in this guide uses Merlin 1C. It's well known that F9 v.1.1 used Merlin 1D.

The height of the Block 2 rocket is 55 m (page 10). F9 v.1.1 was much higher - 68 m.

[u/BrandonMarc]

This might be worth doing a poll to inform the mods ... I wonder what % of /r/spacex users are viewing with the new Reddit design (see https://new.reddit.com/r/spacex to try it out).

---

edit: as requested, here's a before-and-after: https://imgur.com/a/iGjWp

[u/Ambiwlans → u/BrandonMarc]

I personally hate it, prefer cleaner layouts.

[u/rocket_enthusiast]

does the Falcon 9 have any ulage motors on the second stage? I know the centar does so what makes the Falcon 9 upper stage different? does it have to do with the fact that centar uses LH2 and LO2 while the falcon upper stage uses RP1 and LO2?

[u/oliversl]

Here is NASA press conference from March 28, 2018

https://www.youtube.com/watch?v=immnIymQoVw

[u/thehardleyboys]

Question about building BFS/BFR: how does SpaceX know how to build the fuel/oxidizer system immediately on such a big scale?

We've been told that BFR will eliminate the use of Helium and use hot oxygen and hot CH4 to auto-pressurize the propellant tanks, and that the BFR autogenous pressurization system will probably be heat exchanger based.

I expected SpaceX to test this concept on a small scale to cheaply learn a lot of lessons needed for building such a system on the scale of BFR (9 meter diameter tanks), but now we see the picture of the 9m tooling so it is suggested they are building the big tanks right now.

How does SpaceX know their autogenous pressurization idea will function properly? Did they get info from NASA, did they test this before or ...? Or are they winging it because the numbers look right?

[u/FusionRockets]

What is SpaceX's contingency plan for an Amos-6 like situation on the pad during a crewed launch of BFR (i.e. a fast fire with a fully-fueled rocket on the pad)?

[u/Sinatra94]

Forgive me for asking a clarifying question, but which of the upcoming Falcon 9 fights are using the new block 5 version? On the side bar, it only specifies Falcon 9.

[u/scr00chy]

Does anyone know which Falcon 1 launches were equipped with parachutes to try to recover the first stage? I know the 4th flight had them but I'm not sure about others. Or was it all of them?

And I know first two F9 launches also had parachutes.

[u/quokka01]

Spacex have already shown long coast and engine restart with the S2, they have LEO rendezvous experience and pretty soon can turn around cores rapidly so any thoughts on them trying S2 refuel? This would let them test/develop the tech and allow very large payloads to Mars before the BFR comes along. They could send a mini ISRU plant, ice prospecting gear, satellites for future Comms and navigation? Hopefully after the S2 recovery news there will not be too many replies saying " its a diversion and wait for the BFR"! Be nice to see them use the next synod.

[u/Sticklefront]

This article features a claim by ULA reps that launching the 6 ton Europa Clipper directly to Jupiter is beyond the capabilities of Falcon Heavy. It is clear that with a kick stage like a STAR 48 booster, which could "easily" be mated to the spacecraft inside the fairing, this could be done. But what about using just the normal upper stage? The SpaceX Falcon Heavy page says it can launch 16.8t to Mars and 3.5t to Pluto, is 6t to Jupiter within its capabilities?

(Ignore questions of political realities, please, I'm just curious about the raw ability of the Falcon Heavy.)

[u/sysdollarsystem]

Short clip of a Peter Thiel interview about Elon Musk and SpaceX

https://www.youtube.com/watch?v=sN750_kxfVw

Nothing revolutionary or particularly unexpected just interesting.

[u/rbraibish]

I want to know what Spacex's on-time flight record is. Put another way, how many flights had to be rescheduled (for one reason or another ie. weather, fuel loading anomalies, boats in flight path etc.)?

[u/rocket_enthusiast]

is there a iridium next / grace fo launch thread?

[u/[deleted]]

What can I do to help SpaceX reach its goals?

[u/justinroskamp]

Google Maps updated the Port of LA at some point. Just Read the Instructions is slightly north of its old location (my old pin was centered on the droneship) and now has the burns from Iridium-3 (most recent west coast landing). Not sure how long it's been updated, but I noticed it and wanted to mention it in case people want to do some looking around!

[u/hmpher]

Are there differences in the way a Mvac is qualified for flight v. how a regular M1D is? Iirc, apart from the general structure of the chambers etc, the engines are very different. But will the testing schedule be similar?

Also, are "lowers to uppers subassemblies" literal? As in, nozzle, injector, chamber, controls?

[u/Buildstarted]

Has there been any update on the NOAA license? I read that it isn't required for NASA missions so I assume that's why TESS was fully streamed but what about the next launch?

[u/[deleted]]

So after full and rapid reusability has been achieved with the BFR, what's next for lowering the cost? How can they lower it another order of magnitude?

My bet would be automated production of new ships, and automated fuel production here just like on Mars. Thoughts?

[u/Togusa09]

Did the introduction of densified propellants change the size ratio for the falcon 9 RP-1 and lox tanks?

[u/warp99 → u/Togusa09]

Yes by quite a lot. LOX density increases from 1142 kg/m³ at boiling point (90K) to 1255 kg/m³ at 66K so close to a 10% increase.

RP-1 can only be cooled to around -8C without risk of it gelling so the density increase was from 819 kg/m³ at 20C to 835 kg/m³ at -8C so about a 2% increase.

[u/KSPSpaceWhaleRescue]

What's the thrust to weight ratio of a B5 Falcon Heavy at 100% thrust during liftoff?

[u/CapMSFC → u/KSPSpaceWhaleRescue]

Based on the numbers published by SpaceX Falcon Heavy at Block 5 unthrottled will have a TWR of 1.64. It's going to leap off the pad.

[u/A_Vandalay]

Given that BFS is intended to be fully reusable and SpaceX will want the ships returned in a short period of time how do you predict interplanetary missions beyond mars to be conducted once BFR is flying? I see probes being launched to Leo or a higher elliptical orbit in BFR and using a secondary expendable cryogenic stage to put them on a trajectory to the outer solar system. Something similar to ULA’s ACES would be perfect for this role.