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SpaceX successfully launches and recovers second Falcon 9 in 48 hours (techcrunch.com)
507 points by janober on June 25, 2017 | hide | past | web | favorite | 201 comments

Incredible time-lapse of the landing, from Elon Musk's instagram: https://www.instagram.com/p/BVxysOlA04j/

The yawing motion at the beginning of the video is because they moved the drone ship to avoid stormy seas, so the stage had to thrust sideways to retarget. In calm weather SpaceX positions the ship right along the ballistic path, so the stage only needs to pitch up and "flip."

You can also see the grid fins "pulling up" through the atmosphere to bleed off as much speed as possible. I described the optimization a while back. https://news.ycombinator.com/item?id=14288431

Fantastic job to everyone at SpaceX!

That comment is worth a read, I had no clue they were actually generating lift on the body to reduce fuel/etc. Incredible stuff.

Thanks. I made a mistake in that comment, saying the lift/drag of the Shuttle was 1. The hypersonic L/D was 1, but during subsonic approach it was 4.5. In hindsight it kinda makes sense that wings do something. :)

The maneuver is more noticeable with the new titanium grid fins (needed because the old aluminum ones caught fire from aerodynamic heating). Not only are they larger, but they use a "sawtooth" leading edge that increases control authority. New: https://twitter.com/elonmusk/status/879065552060260352 Old: http://www.spaceflightinsider.com/wp-content/uploads/2015/12...

They also happen to be the largest titanium forgings in the world. https://forum.nasaspaceflight.com/index.php?topic=42544.340#...

Well, the plan is to use forging to make them, but the ones on this rocket were cast as a blank and machined. One presumes that they are still working on the forging system. https://twitter.com/elonmusk/status/878821062326198272

Saying in aviation: If you put a big enough engine on it, even a brick will fly.

In this case, it's "given enough initial velocity and control authority, even a brick will glide", but the spirit is the same.

I believe the proper term is "brick sthouse".

A few years back a group of engineers decided to prove this by attaching a number of solid fuel rocket engines to a port-a-potty and launched it to great applause.

In RC planes community it's quite common as well :) With modern brushless engines and LiPo batteries aerodynamics becomes optional.


The new and improved grid fins debuted on this flight allow them even greater capabilities in that regard (greater control authority means they can achieve a higher angle of attack).

It's sad to click on that video and see conspiracy theorists claiming that it's poor CG. Seems no matter how great your achievements there will always be people there to try to bring you down.

I love how Elon Musk feeds the trolls like saying launches are done at night because "it's much easier to do the CGI that way"


It always happens, but really, they're just trying to hook anyone they can. When it comes down to it, there is everyone, and they are the else.

There will always be some who slip between the fingers of education lifting us up.

By "pulling up" do you mean tilting? I read your other comment but had trouble understanding the effect. Do you think you could draw a quick diagram?

First off, the perspective is confusing. The camera is located on the right side of the rocket (I'm treating the zenith as "up" and the direction of flight as "forward"). So when it pulls to the left shortly after the engine shuts off, the vehicle is really pitching up while in a steep dive.

The goal of this maneuver to lengthen the descent path, which in the absence of an atmosphere would be a pure parabola (or more accurately, a suborbital ellipse). Passing through more air means shedding more velocity due to drag, and therefore less fuel is needed to land. Geometrically the best way to do that is to pitch "nose up."

No drawing skills except shitty MSPaint, but that's never stopped me before. https://i.imgur.com/VLYXDOf.jpg

This is becoming really astonishing. It's more and more fitting the quote “They did not know it was impossible so they did it”

I mean, the company was founded only 15 years ago, they started (with success) launching stuff into space only 10 years ago and now it feels like they are able to launch rockets into space every week. Reusable rockets should we add.

Musk very often sets impossible deadlines, but in this case, even if you take a step back, it's scary to make 10 years predictions based on this company track record !

>they started (with success) launching stuff into space only 10 years ago

They really didn't start off with success. Their first 3 launches (on the Falcon 1 platform) were failures. If I remember correctly it nearly bankrupt the company and Musk himself ended up pouring a ton of money into it to keep them afloat.

It was a pretty rocky start for them as a company, and in my mind that makes it an even cooler story. They started with nothing, failed their first 3 attempts at launches but just kept at it, and they are now consitered at the top of the field less than a decade later.

Yeah they actually started a bit sooner (2006) but the first 3 launches failed. And yeah - it makes it an even cooler story in my mind too.

It reminds me of how close to the edge Fedex was before the Vegas trip to save the company.


I mean, NASA helped them a ton based on their previous research to this point.

Going forward I'd expect some slowdown.

But yes, very impressive IMO that he won all the necessary investments and contracts. My bet is his buddy Theil (idk not really buddy, but collegue) helped out with that.

This--there's a reason they are headquartered where they are. What they've managed to accomplish in such a short time is amazing but let's not forget that it was massive US gov't investment in NASA and SpaceX's neighbors Raytheon, Northrop Grumman, Lockheed Martin, etc. that made this all possible.

The US military is currently spending $400m per launch with ULA. Now with SpaceX, they pay around $100m per launch.

Whatever investment the US government have given to SpaceX, they'll get it back very quickly now that competition exists in the launch market.

Isn't half of that 400 million a kind of retainer to keep ULA available? I thought they're still paying that, so it's not much cheaper yet. And they might still need to pay it to someone.

Yes it's a retainer but still a cost and hopefully ending shortly.

I think the point is that the 400-to-100 figure is not Apples to Apples. Imagine 20 years from now SpaceX' ITS has failed to finance and their Falcon Heavy is a loss leader because too few payloads need it and the rest has moved on to a new rocket. This is like the USGov paying them a few billions a year to keep Falcon Heavy around because it's the only rocket with some specific capabilities. IMO depending on the specifics this is not so unreasonable. It's still great that SpaceX has achieved a factor of 2 improvement already for the base price compared to ULA, which doesn't yet include reusability, but one shouldn't overstate how much ahead they are.

Going forward I'd expect some slowdown

Slowdown in funding or launch pace?

SpaceX is cutting launch costs significantly. I suspect that many satellite projects that weren't viable before will become viable now, thus increasing launch pace.

A quote from BulgariaSat (launched 2 days ago):

“People don’t realize that, for small countries and small companies like us, without SpaceX, there was no way we would ever be able to even think about space."

"With them, it was possible. We got a project. I think, in the future, it’s going to be even more affordable because of reusability.”

That's kind of odd, to me, since the Russians aren't that much more expensive than SpaceX, and the pricey bit is usually the payload.

The Russians are only at that price point due to the competition from SpaceX, but the big problem with Proton is the high insurance premiums due to their reliability issues.

Does anyone know what Proton insurance costs these days?

Perhaps it was a combination of low price (even lower since they got a re-used first stage) as well as the option to go rather soon (again, due to the re-used first stage). Don't know how full other launch providers' manifests are at this point.

Slowdown in development pace I believe.

Not to take anything away at all, but a large part of the rocket development until now was based on an existing knowledge base from NASA.

Going forward, there's going to be more and more uncharted territory, so things will likely progressively slow down, relative to the astonishingly fast development pace up until this point.

That premise doesn't inherently follow at all. Quite the opposite.

The uncharted territory combined with Musk & Bezos being willing to do audacious things with billions of dollars, is why breakthroughs are about to accelerate again. With scale and greater R&D capabilities, SpaceX will (perhaps along with Blue Origin and others) be responsible for the next great leap forward in space technology - finally.

Whereas the US Government launch platforms, through NASA and ULA, had been extremely stagnant in several areas that SpaceX & Co are operating in, due to eg wild (but typical) Congressional incompetence (constantly shifting goals, setting up the context where ULA was granted a monopoly (again due to Congressional incompetence or worse)). The Space Shuttle was an absurd production in all regards, it set US launch progress back decades due to the hyper bloat / cost that was entirely unnecessary. The Shuttle was the space equivalent of the F35, a boondoggle that isn't really great at anything and costs several times what it should have. Now that the incompetent Congress is much further removed when it comes to deciding which way to go (how to get there, why, etc etc etc), space tech will accelerate again.

Consider the capability they had with Saturn V and Apollo. Also, compare how easy it was to make Skylab happen, compared to the ISS. With the Saturn V, a smaller people launcher and Apollo they could have done so much more.

Imagen the next Space station after Skylab, they could have launched 4 Saturn V and launch a Skylab size station each time, creating a vastly bigger station then ISS at a minimal cost.

Now they are recreating the capability with SLS and Orion at a cost that is so absurdly high that its hard to even wrap you head around the numbers, specially when compared what the pay for COTS and CommercialCrew.

Anyone who's in DC should check out the Skylab module in the Air & Space Museum. It's remarkable how big it is.

I have not seen it, but I think the internal volume is very impressive. Compared to the ISS that looks more connected mining shafts.

Yeah, I accept this argument, but I guess the point I was trying to make is that, as always, they're standing on the shoulders of giants, and Musk is the first to acknowledge the huge contribution from NASA towards their success.

I'm rooting for them though to keep doing what they're doing.

Not to take anything from NASA, but a large part of their rocket development was based on an existing knowledge base from the Nazis. NASA has done little to make successful reusable space technology, and abandoned any attempts with the SLS.

Liquid fuel rocket technology initially came from privately funded Goddard and the privately funded Society For Space Travel (VfR) that was later funded by the German Army Weapons Department.

See "V-2" by Walter Dornberger

The V2 had solved the major problems with scaling up a liquid fueled rocket, such as the turbo-pumps and the boundary layer cooling of the nozzle.

Well, Germans. I wouldn't necessarily call Wernher von Braun a Nazi.

He wasn't just a member of the NSDAP, he also joined the SS. He's on the record suggesting the use of forced labour of concentration camp prisoners to build his rockets. That's at least an 8/10 on the Nazi scale. Don't whitewash his past just because he went on to build the moon rocket.

It's also interesting to see how much more apologetic the English Wikipedia article on von Braun is compared to its German counterpart.

He _was_ a nazi party member. We don't know if he really _meant_ it though.

Well, the choice was basically,

* Become a member of the Nazi Party

* Death

After WWII he didn't:

* Commit Suicide

* Exile himself to South America

* Face trials for War Crimes

He did:

* Become a public figure used to sell the space program

* Help an Allied power with extremely advanced military and scientific intel

* Help put someone on the Moon in a completely unrealistic time frame

* Become privy to extremely top secret information

I'm going with, "not a Nazi" on this one, personally.

> Well, the choice was basically, > * Become a member of the Nazi Party > * Death

No it wasn't. This is what Nazi's say to excuse their decisions and behavior. There were millions of people in Germany in both industry and the military who were not Nazi's and survived just fine.

Note that unlike Von Braun many other Germany scientists and weapon designers were not members of the Nazi party (let alone enthusiastic members)

Becoming a Nazi and joining the party is what a person consciously did either because they believed in the ideology or they wanted to collaborate to further their careers.

Van Braun being washed of his Nazi part is a conscious part of a US government propaganda campaign as Von Braun having safe haven in the USA in the 1950s was very controversial at the time. It's as simple as the USA overlooking his Nazi past and excusing it (and actively covering it up) because the cold war necessitated it.

edit: forgot to mention, Von Braun wasn't just a member of the Nazi party - he was a member of the SS - there is zero feasible explanation for becoming an SS member. There is also the small matter of the war crimes he took part in with the enslaved labor at his factory in Peenemünde.

>Van Braun being washed of his Nazi part is a conscious part of a US government propaganda campaign as Von Braun having safe haven in the USA in the 1950s was very controversial at the time.

I honestly thought this was common knowledge amongst people who know who Von Braun was.

He was a Nazi collaborator and party member in full blood. As you noted, explaining his actions with the camps he ran would be an interesting exercise for any apologist.

> There were millions of people in Germany in both industry and the military who were not Nazi's and survived just fine

Well, let's talk about that. How many of those millions who were both in both industry and the military AND ALSO were rocket scientists?

> Note that unlike Von Braun many other Germany scientists and weapon designers were not members of the Nazi party (let alone enthusiastic members)

For example? I'm not here to post up your argument.

> Becoming a Nazi and joining the party is what a person consciously did either because they > believed in the ideology or they wanted to collaborate to further their careers.

It's not apocryphal to say that full German citizens not persecuted for the racial background joined the Nazi party to escape suspicion of infidelity to the Führer's master plan of Aryan takeover, especially if you were an intellectual. Let's bring up another member of the Nazi party: Oskar Schindler. Tell me your criticism of Mr. Schindler. Was he acting in a purely selfish way?

> There is also the small matter of the war crimes he took part in with the enslaved labor at his factory in Peenemünde.

OK, let's talk about another German with the scientific mind whose knowledge and genius was enough to kill thousands of people: Albert Einstein. Do we blame him for Hiroshima, Nagasaki, the Cold War, and the tens of thousands of live nuclear warheads? His choice was similar: Death (as a Jew in Germany), or help make the A Bomb. Should he have chosen, "Death"?

> For example? I'm not here to post up your argument.

Easy as looking at the other V programs. Fritz Gosslau was the designer of the V1 - not a Nazi. August Coenders was the chief designer of the V3 - also not a Nazi. Robert Lusser worked on engines - not a Nazi (ended up at NASA). Hans von Ohain, designer of the jet engine and worked on the ME232 - not a Nazi. Walter Thiel was the head of the research lab at Peenemünde - not a nazi. Klaus Riedel worked on the rocket with Von Braun - not a Nazi.

All of Von Braun's deputies also weren't Nazi's (at least in the research part, I think it is fair to say that his subordinates in the SS were Nazi's).

It would actually be easier to list those of the Wehrmacht and in science / industry who were Nazi's (or were sympathetic to them) - since most certainly were not. Most famously that would be Albert Spier, the Krupp family, Erich Schumann of the nuclear program, Göring, etc.

Most of the military high command weren't Nazi's (or technically, sympathetic to the Nazi's since it was illegal to be both in the military and a member of a political party). They despised Hitler, as they despised Bizmark before him - because the German military had always been famously independent of civilian leadership and its own organization. Hitler taking the reigns of military strategy was the antithesis of how these guys had been bought up and trained.

> Tell me your criticism of Mr. Schindler.

He was a Nazi, until he changed sides. He assisted the takeover of the Sudetenland with his spying.

Schindler regretted his actions and worked against the Nazi's. Von Braun never did that - he just tried to minimize his role. Plus even Schindler never joined the SS.

None of those designers had to join the Nazi party or SS because Von Braun did it for them. He was told he had to suck up to Himmler to protect the program. He was obviously ambitious and it suited his ambition well, but he was also protective of his team.

And Von Braun ended up being arrested by the Gestapo for perceived disloyalty. Hitler only approved his release after Speers entreaties that Von Braun was indespensable.

Stop using the greengrocer's apostrophe. The plural of Nazi is Nazis, with no apostrophe.

Acceptable uses of the apostrophe:

  glottal stops
  disambiguation in transliterations
Yes, I am aware of the moniker applied to those that nitpick grammatical errors.

>It's not apocryphal to say that full German citizens not persecuted for the racial background joined the Nazi party to escape suspicion of infidelity to the Führer's master plan of Aryan takeover, especially if you were an intellectual

This is simply false, as the other poster has given you many examples of. This is once again straight out of propaganda and an attempt to normalize Nazi war crimes.

>OK, let's talk about another German with the scientific mind whose knowledge and genius was enough to kill thousands of people: Albert Einstein. Do we blame him for Hiroshima, Nagasaki, the Cold War, and the tens of thousands of live nuclear warheads? His choice was similar: Death (as a Jew in Germany), or help make the A Bomb. Should he have chosen, "Death"?

Huh? What are you talking about? Albert Einstein was not forced to help J. Robert Oppenheimer. He returned to the US in 1933 and stayed there as a professor after his property was seized by the Nazis in Germany and they put a death mark on his head. Six years later in 1939 he agreed with Hungarian scientists to warn the US of German atomic weaponization research, and he himself made these choices, leaning on diplomatic favor to do so.

It was only a year before his death that he admitted it was a great mistake; but felt justified in the time he made the decision given the alternative of the Germans developing the weapon first.

I really have no idea where you are getting your alternative history facts, but they are not only incorrect but often run counter to what actually occurred.

> Albert Einstein. Do we blame him for Hiroshima, Nagasaki, the Cold War, and the tens of thousands of live nuclear warheads?

Well, no. He had nothing to do with any of those things, except for signing a letter that someone else wrote, telling Roosevelt about the possibilities of nuclear fission. He didn't discover fission, and was never part of the Manhattan Project, or post-war and cold war nuclear weapons research and development.

>Van Braun being washed of his Nazi part is a conscious part of a US government propaganda campaign as Von Braun having safe haven in the USA in the 1950s was very controversial at the time. It's as simple as the USA overlooking his Nazi past and excusing it (and actively covering it up) because the cold war necessitated it.

First I've ever heard of that. Do you have any proof of that? If it was very controversial, there's sure to be articles and discussions about it, right?

Two books cover it extensively, Apollo[0] and Red Moon Rising[1] - I can't remember the exact date, but at some point even Albert Einstein wrote a letter opposing Von Braun.

By the mid-50s his history had been all washed over and forgotten, and it wasn't until the 90s that the issue was broached again.

There is no reason for the coverup to continue today or for anybody to still believe it - there is a lot of testimony about Von Braun overseeing hangings and the deaths of thousands of slave workers. Had he not been useful for other purposes it is almost certain that he would have hung at Nuremberg.

[0] https://www.amazon.com/Apollo-Race-Moon-Charles-Murray/dp/06...

[1] https://www.amazon.com/Red-Moon-Rising-Sputnik-Rivalries/dp/...

That it's the first you've heard of it doesn't mean Google suddenly stopped working or that the GP is under any obligation to provide you with proof.

Aside from the serious history stuff that you haven't even tried to find, it was the topic of a song by Tom Lehrer, America's greatest political satirist:



Von Braun became an SS member when told he had to to protect the program. He was obviously ambitious and it suited his ambition well, but he was also protective of his team.

And Von Braun ended up being arrested by the Gestapo for perceived disloyalty. Hitler only approved his release after Speers entreaties that Von Braun was indespensable.

  >Well, the choice was basically,
  >  * Become a member of the Nazi Party
  >  * Death
That's not true. No more than 10% of the German populace were Nazi party members at any given time. In fact, it was illegal for soldiers to join political parties until after the war started, and even when they were allowed to join most of them didn't.

Of course joining the party is always your ticket to wealth and power in a totalitarian system, so it's not surprising an administrator like von Braun would be a party member even if he was completely disinterested in the party ideology. It's also not surprising he joined the SS when pressured directly by Himmler to do so. Himmler wasn't the kind of guy you said "no" to.

To all accounts he supported the party in the '30s because the Nazis were promising to reverse the injustices of the Treaty of Versailles. And he probably soured on the party by the time he was arrested and accused of sabotaging the program he was running (for which he could have been shot).

Clearly he knew what was going in in Mittelwerk. How much culpability you assign is an open question.

And it's not surprising he didn't off himself or hide after the war. He had something very valuable to offer whomever took him in, so that's not very dispositive as evidence of innocence.

The choice was becoming a member for cozing up with all the important decisionmakers of the time or giving up getting any of that incredibly fancy (at the time) rocketry research funded. He clearly loved his rockets, to the point where he did not mind becoming a nazi for them, or a yankee or whatever other affiliation that might have allowed him do do his research.

I think what you're saying is "because the choice was become a Nazi or death, he became a Nazi but was also not a Nazi"

Uh. Others below disagree with the "or death" part and back up with citations, but ignoring that, the statement is not particularly logical on its own terms.

Well he was arrested by the Nazis and could have been executed had Speer not interceded.

I'm sure that Nazis have arrested errant Nazis from time to time. Being arrested by a cop doesn't mean that you cannot be a cop yourself. And it seems like the Nazis paranoia levels were high: https://en.wikipedia.org/wiki/Wernher_von_Braun#Arrest_and_r...

That's just evidence that he needed to be a party member and SS member to protect himself and his team. Because he wasn't more cooperative with Himmler, he got arrested under charges that Himmler trumped up.

To make a bad analogy: Werner von Braun running the US spaceprogram is about as controversial as making Osama Bin Laden the building inspector for NYC after 9/11.

I don't know if he aligned with the Nazi goals necessarily but he certainly loved his rockets enough to look over the fact that tens of thousands of forced laborers worked under terrible conditions for his toys and thousands of people died in Britain.

Thiel ousted Musk from Paypal, and even though they don't seem to be antagonostic these days, I don't see them doing each other a lot of favors.

I would disagree. Founders Fund (Peter Thiel one of 3 founding partners) was the first major outside funder of SpaceX with a $20 million investment after the 3rd Falcon 1 failure and before the successful fourth launch. This investment was critical and risky for Founders Fund. It would have allowed SpaceX try few more launches, if the fourth had failed.

SpaceX have several thousand of their own satellites to launch in the coming years, if anything it will speed up.

>I mean, NASA helped them a ton based on their previous research to this point.

I'm not sure that's true. What did NASA help them with, exactly?

IIRC NASA basically gave SpaceX the patents and designs for the turbopumps that the Merlin engine is built around. They also committed to some contracts very early and funded Dragon development at a time when no commercial operation would have trusted SpaceX with a contract of that size.


"The SpaceX turbopump was an entirely new, clean sheet design contracted to Barber-Nichols, Inc. in 2002 who performed all design, engineering analysis, and construction; the company had previously worked on turbopumps for the RS-88 (Bantam) and NASA Fastrac engine programs."

IIRC there was also at least one DoD contract in the Falcon 1 era that surely helped as well. I recall reading a few references to it and remarking how odd it was. Some real invisible hand stuff. Since then I've noticed one other project was sustained by military contracts. EMC2 (polywell fusion) got several years of support from the US Navy via small (few $million) contracts. Last I read, they had validated the physics and were looking for civilian investors to fund a large machine.

The US government has pots of money they use to buy flights on unproven rockets, that's how SpaceX got a contract for STP-2 as the 2nd flight of Falcon Heavy. Falcon 1's first two flights got some revenue from DARPA and the Air Force ORS, and flight 3 from NASA. (All failed.)


Sure, even Musk will admit SpaceX wouldn't have survived without financial help (in the form of contracts) and facilities use from NASA.

But in terms of actual technology... not the turbopumps, certainly, unless your logic is "the contractor SpaceX used to design its turbopump developed expertise on NASA (and other) contracts".

This is becoming really astonishing. It's more and more fitting the quote “They did not know it was impossible so they did it”

More like, they know it is possible so they did it.

Indeed, given how Musk operates, you're right. (however, there's no quote in that sense :) )

  Somebody had to, no one would
  SpaceX tried to do the best they could

>It feels like they are able to launch rockets into space every..

Not it doesn't. Stop trying to spread false impressions. This site is a discussion platform, not an advertising one...

They've been doing about 2 rockets a month now for the past 2 months, and there's [plenty of indication][1] that they're going to maintain that cadence well into August. The idea of them stepping that up to 1/week sounds pretty plausible to me, especially once they have a few more pads available to launch from.

[1]: https://spaceflightnow.com/launch-schedule/

Are you saying that his opinion was a false impression? Seemed like he was discussing the topic at hand.

Those are not mutually exclusive..

This perception will change the moment one of the rockets explodes, though. It's ~impossible to ride an explosion into space hundreds of times without a catastrophic failure, so I'm just hoping the consequences won't be too bad.

They've had many notable failures, from the first 3 attempts to launch a Falcon 1, to two different Falcon 9 failures -- including destruction of payload -- with major consequences and delays that resulted:



Each did diminish their reputation, but they have kept going. They can weather more failures, and every launch is still pretty nerve-wracking.

The stakes will be higher when they start carrying people, perhaps next year.


The crew escape system on the Dragon as described by your link is a huge advance over the Shuttle. So while a launch failure on a manned flight is likely inevitable, casualties are not.

All manned spacecraft in history had launch escape systems (or at least ejection seats, on Gemini and Vostok). Except for the Space Shuttle... The Dragon 2 system is a first though, in that it uses liquid propellants and is highly controllable - as opposed to throwaway solid rockets used everywhere else.

One of 'em already has. Look up Amos-6.

Right, and both of those had some consequences regarding PR.

I meant to call attention to the fact that we're doing manned missions soon. It's a bit different having an unmanned rocket explode.

Hopefully it won't matter at all. The world might be ready for a "Well, that sucked. Let's move on" type mindset.

Disclaimer: I work at SpaceX as a technician.

Certainly manned missions have an added element of concern due to the risk to human life, but even unmanned failures have consequences beyond bad PR for those involved in the launch. This isn't specific to SpaceX, I'm sure it's the same for anyone involved in the launch industry, and there's no way to sugar coat it, but its an extremely shitty feeling to work on a piece of flight hardware for weeks/months at a time, see it go through build, test, certification, and then see it fail during launch.

In many ways it's even worse when you realize that your rocket is carrying a payload that many other people worked just as hard on, often over even longer periods of time, and in the case of some scientific payloads may not have the ability to relaunch due to budget/time constraints, and they have entrusted you to get this payload to orbit and you have failed them. I wish I had a more sophisticated way of describing it, but its overall just a very shitty feeling.

Disclaimer: I build web apps that don't really mean much at the end of the day.

Not sure if this will help that shitty feeling when things go wrong, but SpaceX has given me an AMAZING feeling that I was a little worried humanity as a whole wouldn't feel again. All the hard work is appreciated!

I'm just a low level cog in the wheel here, but hearing things like that is certainly very nice.

I wouldn't sell yourself short though, rocket launches tend to make for good press, and often make the front page of HN, but anyone who works hard at a job is worthy of respect whether they're building web apps, or spaceships, or anything else.

I just want to add that there are a whole lot of us rooting for you and worrying every time you guys launch, and doing our best to share your pain after the failures. Low level cogs are still important and you're doing amazing stuff.

> I wish I had a more sophisticated way of describing it, but its overall just a very shitty feeling.

Maybe a song would do?

I mean, there is some relatively obscure but otherwise great music praising the dream of space and the work of people involved. See e.g.:

- https://youtu.be/6zotaRLROtw - A Toast For Unknown Heroes

- https://youtu.be/GbL3oNEDvJ0 - The Ballad of Apollo XIII

- https://youtu.be/ab_mH8R0KTM - One Way to Go (possibly the single work of art I ever found that plausibly praises capitalism)

(lyrics googlable by song title)

Also see pretty much all the work of Leslie Fish and Julia Ecklar.

I feel that now might be a time to start developing songs for the coming second Space Age - and hopefully to reinforce the dream this way. If anyone here does music / songwriting (or knows someone who does), I urge you to try (or suggest it). We need it :).


Also, to lighten the mood:

  (This verse is dedicated to the management of Morton Thiokol.)

  So first let's pray to Vulcan, ugly god of forge and flame,
  And also wise Minerva, now we glorify your name,
  May you aid our ship's designers now and find it in your hearts
  To please help the lowest bidders who've constructed all her parts!

  So pray to great green Mother Earth and the grim old god of Space,
  And the gods of flame and metal whom we've summoned to this place.
  Oh you gods of flight and physics, now you have us in your care;
  We hope that you will listen to a rocket rider's prayer.
https://www.youtube.com/watch?v=3WLE6FpAcVs ;).

How much refurbishing goes into preparing a previously used rocket before it is reused?

What technological breakthrough of recent times has made this sort of quick inspection and reuse possible, that was not possible earlier?

I don't mean to be evasive, but there are a couple of reasons why I'm uncomfortable answering such direct questions that may involve internal procedures:

1. I'm not nearly knowledgable enough about the overall refurb process to give you an in depth answer. The best answer I could probably point you towards is this article[1] quoting our President Gwynne Shotwell. It won't give you the specifics you're looking for, but it will give you an idea of the costs in relation to a new build. Seeing as labor is a fairly large cost component of the rocket overall, this gives you some idea of the potential extent of refurbishment vs building a new rocket.

2. Even if I did have the requisite knowledge to answer your question, those kinds of internal procedures aren't something I could share. My apologies.

As to what breakthroughs make this sort of inspection and reuse possible, and I'm not saying this to be pithy, the biggest component is simply that the stage lands on a solid base rather than being dunked, or slammed into to be more accurate, highly corrosive salt water. Reusability isn't so much a function of any huge advancement in inspection so much as the ability to execute a controlled landing of the first stage. Although there are quite a few advancements in metallurgy and materials science, not to mention NDT procedures, that do increase the life span of components.

I know this probably does a very poor job of answering your questions but it's the best I can do.


> so much as the ability to execute a controlled landing of the first stage...

Pardon me if I am wrong here. But it seems to me that you are suggesting that most of the damage that a rocket sustains, that makes it not fit for reuse, does not happen during the launch and re-entry, but during landing and salt water?

But if that is so, why was this the case with space shuttles?

> Although the Space Shuttle Main Engines (SSME) were reusable and going to be used on the SLS rocket, NASA doesn't plan to reuse them. The refurbishing and recertification costs make reuse more expensive than manufacturing new engines.


Apologies again for not understanding, but I’m unsure exactly what you’re asking with the question why was this the case with space shuttles.

With regards to the SSME, the SSME is an engineering marvel, but it is significantly more complex than the Merlins you’ll find on Falcon, both in initial build as well as refurb. I know a few techs here who used to work on them at Rocketdyne. Raptor will be more analogous to the SSME but there have been significant advancements in metallurgy and materials science since the introduction of the SSME, which should hopefully lead to easier reuse. Also, it should be noted that the SSME were in fact refurbed and reused when they were part of the Shuttle program.

As to your quote from Quora, I find it somewhat ambiguous. Again, the SSME was routinely refurbed and reflown as part of the Shuttle Orbiter. I’m no expert on the SLS program, although I do keep up with things space related, but I’ve yet to see any cost breakdowns of refurb vs new build in regards to SSME specifically. That quote makes it unclear to me whether NASA found that reusing the SSME as part of the SLS program is cost prohibitive, or whether making the first stage of the SLS reusable, which happens to use the SSME, is cost prohibitive. It should be noted that the SSME and RS-25 are largely the same engine, and later flights of SLS will switch to a cheaper non-reusable version of the RS-25. In any case, the first stage of the SLS is going to end up in a giant pond of salt water, along with the attached SSME/RS-25s. SLS was never designed for propulsive landing, and can not be made to do so now, so those engines are ending up in the ocean no matter what. Perhaps the poster means that NASA found the refurb costs of the SSME to be prohibitive after they have been dunked in salt water, again, since this is the only possible outcome with SLS. Obviously if the first stage of SLS landed on solid ground, or a ship at sea, the refrub cost of the SSME would be completely different.

I think we don't yet know what the rebuilding of the production line for the RS-25 will cost. They did promise quite a bit of cost saving because they need not be reusable anymore but as you probably know better then I setting up a completely new rocket engine production will not be cheap.

What damages a rocket depends on the rocket.

For the SSMEs, it was just plain use which damaged them. The SSMEs were engineering marvels, but the ludicrous nature of the Shuttle demanded extreme performance, which meant that they ran on razor thin margins. By the time they finished a ~8 minute burn, they had taken enough of a beating to need a lot of refurbishment. SpaceX's Merlins, on the other hand, are much lower performance and built more for robustness.

Think of it like an F1 race car, which needs a lot of work after every race and a new engine several times a season, versus a daily driver which can probably go 50,000 miles without ever opening the hood. (Not that this is recommended.)

But what specific thing does the SSME's had to do that Merlins doesn't?

In your race car example, you can differentiate it from a daily driver that the F1 car has to endure tremendous accelerations, cornering and down forces acting on it and an engine that reaches insane rpm's that puts tremendous amount of stress on all the critical engine components..

Can you differentiate between these rocket engines in that way?

Sorry I'm typing from mobile so my posts may be even less informative than usual.

The main thing that the SSME has to do that's different from the Merlins is quite simply generate more thrust and a higher specific impulse. The SSME is a much higher performing engine. It achieves this performance through fuel choice and design, namely by using liquid oxygen/liquid hydrogen vs using RP-1(which is basically kerosene) and by being a staged combustion rather than gas gen cycle engine. While it has much higher performance than Merlin, that performance comes at significantly greater overall complexity, particularly in the turbomachinery and pre-burner components.

The SSME also has to run from sea level all the way into space, whereas the Merlin is able to have one design optimized for sea level and a second design optimized for space.

The difference in efficiency is striking. The SSME's specific impulse (the closest equivalent to MPG in a car) is 452 in vacuum and 366 at sea level. Merlin's is 311/282 for the sea level version, and 348 for the vacuum version.

Of course, this is not a criticism of Merlin, just a comparison. By being less efficient, they're able to optimize for other stuff like cheapness and robustness.

I think after the landing the reentry is probably the most problematic. If you can prevent them from burning up and you can land them (and one is implied by the other) you are on a good road.

I think the Space Shuttle engines would have been capable of more direct relights. They test fired them quite a bit and the were reusable. NASA was just taking a now risk approach and did not really push the technology forward.

Boeing has just received a contract for a first stage with wings that should fly 10 times in 10 days and it essentially uses a SSME. So they seem to believe that they don't need to do that much to make it work.

When the inevitable human fatalities are realised, we will see that everyone involved had done their best: SpaceX doing everything they can to make their rockets more reliable, a launch escape system that works all the way to orbit, and dozens of successful launches on the same hardware.

> When the inevitable human fatalities are realised, we will see that everyone involved had done their best:

Have you seen the movie called "the challenger disaster". If not, you should see it. It might helps to gain a bit of perspective about these things.

I don't always have the best reading comprehension but this seems somewhat cryptic. I don't have time to watch a movie at the moment but what was the perspective you gained from it?

Also, I'm always a sucker for a good space related movie, was it any good? I'm not sure which one you're talking about but these are the two I was able to find:

https://en.wikipedia.org/wiki/The_Challenger https://en.wikipedia.org/wiki/Challenger_(1990_film)


The Challenger Disaster(2013) : Factual drama exploring the truth behind the space shuttle Challenger's 1986 disintegration.

Your comment reminded, specifically this part " When the inevitable human fatalities are realized, we will see that everyone involved had done their best:" reminded me of the speech given by someone in charge of the investigation at the start of it..

>I appreciate you all coming together at short notice. We have a huge, vital task ahead of us, upon which might depend the future of manned space flight in this country. Now, I intend for this investigation to follow an orderly and proper procedure. We are not going to conduct it in a manner that is in any way unfairly critical of NASA. Because we believe, and certainly I believe, that NASA has done an excellent job. And I believe that the American people think so too. Anyone?

Of course, it turned out to be not so pretty...

So this exchange is veering dangerously close to me going full on SpaceX shill mode, which I have no desire to do, one for the good of the HN community as I don't think that would be appreciated here, but also for the simple fact that I'm off the clock right now and Elon will need to increase my pay if he intents me to run PR on my off hours.

Thank you for clarifying your previous post as this is what I was thinking you meant, but I didn't want to say anything without being sure. With that being said, and at the risk of sounding overly defensive, I do find it somewhat unkind to call into question the ethics and professionalism of those who work at SpaceX based on a movie about a completely different set of organizations and corporations. This of course isn't to say that there aren't valuable lessons to be learned from those past events, or that we are somehow immune from making similar mistakes, but implying that if such an event befell a SpaceX launch it would immediately be due to a lack of people giving it their best seems somewhat premature.

I do have a well read and marked up copy of both the Rogers Commission Report as well as the CAIB report on my bookshelf, so I can assure you that I and many others do take the lessons learned from those events very seriously. Thanks for the movie recommendation, I'll add it to my to-watch list.

An explosion on a manned flight shouldn't result in anything more than some bruised and disappointed astronauts.

> The world might be ready for a "Well, that sucked. Let's move on" type mindset....

"Well, that sucked (that people are dead)?, but let us move on (like nothing has ever happened?)", is that the mindset you want the world to adopt?

Pretty much, yeah. Exactly what mindset do you want the world to adopt?

We don't want to be careless with human lives, but it's also not helpful to play a finger-pointing blame game every time there's an accident.

>but it's also not helpful to play a finger-pointing blame game every time there's an accident..

It sure is helpful if it can prevent loss of human life in the future, even it slows down the "progress" a bit and some company loses some of its valuation and business...

Is this not what happened with the Apollo and Shuttle programmes? I'm not saying loss of human life is acceptable but the astronauts know the risks when they sign up.

>but the astronauts know the risks when they sign up.

You should see this movie


Two of them. AMOS-6 and CRS-7.

Exactly this.

Funny that very few people see this and instead are already cheering them for doing the "impossible"...

What is it exactly that very few people see considering that SpaceX has already had multiple failed launches?

Per Elon's tweet those grid fins were much better behaved than previous versions. Nothing got hot enough to start showing up in the visible spectrum (good). And what was interesting for me was the lack of gunk landing on the camera. (presumably from the fact that the covering of the fins wasn't burning off like it had in previous flights). What is particularly impressive for me is the slow and steady progress on the 'landed' F9's. The first one successfully landed looked really beat up, and the next couple marginally less so, Friday's went through a part of flight regime that SpaceX had deemed "un-recoverable" and an this one came through looking quite good. Still feels like science fiction to me ...

> Nothing got hot enough to start showing up in the visible spectrum (good).

The new grid fins undergo the same amount of heating, they're just better able to cope with the heat. The reduced heat in this case was due to the much lower energy entry profile (the partial boostback burn killed a large chunk of the stage's velocity prior to reentry, combined with the fact that it was a lower energy orbit in the first place).

Thanks Josh. I went back and reviewed the Iridium 1 footage and saw that even the Aluminum fins had no trouble with this particular launch and recovery option. I am looking forward to seeing the first GTO launch with a booster that has them.

Those fins are awesome:


Cast and cut titanium. They are about 4x5 feet and some of the largest (if not the largest) titanium castings in the world.

Titanium is an amazing material that is super hard to work with (special furnaces), and has its own sets of risks (titanium fire any one). I would love to see what goes into making those things because it simply has to be impressive.

I'm curious why they didn't go the laser-sintered 3D printed route. For low volume items like these I'd imagine that the cost of the moulds and machining would be prohibitively expensive, and printing would let them try some different designs as they lead up to a Block-5 design freeze.

There are a few reasons I could think of:

1 - Most industrial DMLS/EBM systems have a build envelope far too small for this. A system like the Norsk Merke IV might have the required size, but parts built that that process still require post-machining. 2 - Tolerances. Casting -> Machining still offers greater control over the final geometry than additive processes, especially at that scale. 3 - Casting is a bit more design-agnostic than additive processes. 4 - QC processes for casting + machining are far more defined than for additive processes.

None of these are insurmountable challenges, so I'm sure in the future a laser-sintered/EBM/plasma-deposition process will be used or at least heavily-considered.

What would be the advantage? "3D printing" is great for geometries and structures that don't lend themselves well to traditional CNC milling, but a grid fin is a really straightforward part.

As I understand it (and I am not an expert I just enjoy the field) sintered materials retain some degree of porosity (and loose some strength due to this and how the particles are adhered).

This is OK for the average power drill in your house. It isn't critical, and they can compensate for the porosity with extra materials.

If we were replacing a steel part with at TI one, then sintering might make sense, the extra strength, and lowered weight would compensate for the differences in materials.

SpaceX is using laser sintering (generally Inconel) for a wide range of components, including pieces of the engines that flew today.

They make extensive use of laser sintering in the SuperDraco engine (including the combustion chamber, which experiences tremendously high temperatures and pressures).

That being said, laser sintering is great for parts with weird geometries and structures that are hard to machine. A grid fin is really straightforward from a milling perspective, and would take advantage of the strengths of laser sintering.

The launch on Friday used the old fins. During re-entry, one set was glowing from the heat. I really thought it was going to cause a landing failure.

They have always done that. Up until this launch the grid fins were coated with an ablative material that was designed to burn off.

That was just the paint burning off, I think.

Yeah, it's normal for the aluminum + ablative paint version to look Really Alarming during a hot landing.

not as big of a mold, but here: https://www.youtube.com/watch?v=WXFRRg8YMT0, they cast a bunch of titanium hammers at the same time

Nice. SpaceX is finally getting their launch rate up.

As a business, that's been SpaceX's biggest problem. Customers like the pricing but not the long delays. Finally, SpaceX seems to be getting past that.

Getting pad time at Canaveral is a bottleneck. SpaceX is still building their own launch site at Brownsville,, TX, but that's going slowly.[1] All SpaceX has there right now is some fill that's settling (the location is on sand maybe 2m above sea level) and a dish antenna. Next to be built, the fire station. First launch is now supposed to be no earlier than 2018.

[1] http://www.krgv.com/story/35550679/3m-road-project-underway-...

Today's launch wasn't from Canaveral. It was a polar orbit launch, so it went from Vandenberg near LA.

It's still around a two-week turnaround to get a launch pad ready in Canaveral.

Why? Because the exhaust fire burns everything in its path down to the core?

Not down to the core, but part of the process is a couple of days of inspection to figure out which parts need replacing.

If they achieve this launch rate through the rest of the year they should hit about 20 launches.

I like how SpaceX has a "pricing" section on its webpage as if space flight was something mundane and pedestrian like an oil change in your car or something.

Someone a while ago wrote a blog post comparing the pricing sections on various startup websites and how some startups don't have actual prices on the site, and made a comment about how if SpaceX can put a pricing section on their site, your startup can surely manage it too.

Your startup can, but should you? Your competition wants to know what you charge so they can undercut you - or if they choose not to undercut you know how much they have to spin that they are better to account for the higher costs. Either way the competition will use your pricing information against you.

Now there are other considerations. SpaceX has a number of good PR reasons to want to be upfront about their costs (their competition is regularly accused of cheating the government every election cycle). If you sell retail your customers will ignore you if you don't have pricing information.

It's not just competition. In most markets, your customer's willingness to pay follows a power law: you'll have one customer who's willing & able to pay an exorbitant amount, your next biggest might pay 50% less, and so on down, until you get to the mass market who all want your product for $99.99. Companies that operate at the head of the distribution (i.e. most B2B companies) want to be able to practice price discrimination, and charge that one whale what they're actually willing to pay. Otherwise, they could be leaving a significant amount of money on the table.

The competition aspect is pretty commonly worked around - basically every B2B company I know has no compunctions against calling up a competitor, posing as a potential customer, and getting a price quote for competitive research. Or if they have slightly more compunctions, they'll call up a market research firm, hand over some money, and the market research firm will call up all the competitors in the industry, pose as a potential customer, and sell that information back to all the competitors in the market.

I suspect that SpaceX's published price tag is really there to motivate the employees. It's a reminder that Elon's goal is to make spaceflight a mass-market product that an ordinary middle-class citizen can afford, and so he wants that number to go down over time. In many B2B markets without price transparency, there's a tendency towards lazyness on the engineering side; when your revenue comes from how effective your salespeople are at jacking up the price, there's little incentive to focus on small efficiencies that keep the overall price down. Elon wants to keep the focus on small efficiencies so that the price gets low enough that it becomes an everyday thing.

My take is that if your competition is trying to undercut you then either you charge too much, or they don't have a lot to offer aside from a low price.

I used to work for a company that had a single product and sure we've lost a few customers to our competitors because of our pricing, but judging by what they chose instead I don't envy them.


(Granted, SpaceX did it first)

I watched the three promo movies on their website; it's interesting how much they focus on the "cheaper price tag != better" angle, by highlighting savings coming from better reliability ratings (= better insurance) and more reliable launch schedules. Feels like an obvious dig at SpaceX ;).

You have to sell what you have, and that's what they've got.

ULA's insurance rates are not significantly different from SpaceX, btw.

It may be not that long before we see: "Create an account to reserve your spot for our space tours!" followed by a form to fill in your information and a Checkout with PayPal button. Reserving a spot for a space tour. No big deal.

Take TLE of all Irridium-NEXT satelites... http://celestrak.com/NORAD/elements/iridium-NEXT.txt

... and import it to Stellarium http://www.stellarium.org/wiki/index.php/Satellites_plugin

P.S.: Stellarium 0.16.0 released few days ago! https://sourceforge.net/p/stellarium/news/2017/06/stellarium...

Any idea how I could get a copy of Stellarium 0.16.0 compiled for Raspberry Pi?

Did anyone else notice that the engines shut off while the rocket was still a small ways up, after which it fell quite heavily onto the landing legs?

Yes. Probably due to pitching drone ship deck due to heavy seas, the stage reached zero vertical velocity above the deck and had to shut down. Even at the lowest throttle setting the first stage still has a TWR > 1 and cannot hover without accelerating upwards again, so calculating the "suicide burn" timing is really crucial.

edit Corrected "TWR > 0" to "TWR > 1".

Is that TWR (Thrust to Weight Ratio) for when all 9 Merlin engines are lit? Landing burn today had 3 lit if I recall correctly.

No, that's for a single engine. At landing, the first stage is nearly empty, and thus very light. Even the single center engine alone, throttled as low as it will go (40% or something like that, I don't think we have the exact number for the Merlin-D), produces too much thrust to be able to hover. The Grasshopper and F9R testing vehicles carried extra ballast to be able to hover and descend under thrust without cutting their engines.

That's pretty cool. Makes sense, especially with stage 1 being so light on re-entry that a single engine would have a TWR > 1.

The landing burn actually used one engine initially, then three, then one again for the last bit. It doesn't burn three all the way through the landing burn.

Might be an artifact of the weather conditions, which was said to be less than ideal.


Probable wind gust right before landing.

He's talking about friday's landing that came down very hard and used up pretty much all the emergency crush core in the legs, because it came down on the side of the ship, then overcorrected to the other side, then corrected again and touched down (speculation, but pretty obvious when you look at the scorch marks on the ship)

Yesterday's "jump" for the last few feet was probably due to the ship going up and down with the waves and the rocket not expecting it

they call it a "hover-slam" landing

The idea of the hoverslam is to arrive at zero vertical velocity at exactly zero altitude. This is complicated, but can be done fairly reliably when "zero altitude" is stationary - on land landings or drone ship in calm seas. In heavy seas as today, the drone ship deck is pitching up and down, and it's really hard to predict the altitude it will be at the exact moment of touchdown. If I had to guess, I'd say the calculations are done against the highest possible or average position of the deck, and during today's landing it was at its lowest point at the moment of arrival, causing the stage to drop the last meter or so. This is what the crush cores in the landing legs are for :)

I wonder if they will build more stable landing platforms. If you look at oil drilling rigs, they stay calm even in relatively heavy waters.

But oil rigs aren't easily movable, and they will want to get the rocket back to land. I suppose they could crane it across onto a drone ship barge, but landing directly on the barge in the first place seems to be working out ok so far and saves a huge amount of extra cost, time and trouble.

I believe oil rigs are heavily anchored. I believe the barge either has no anchors, or less (or less massive ones.)

It's not about having anchors, it's about not being affected by the top layer of water which moves up and down due to waves. If you submerge (your center of gravity) just a few meters under the surface, you'll suddenly be much more stable and much less affected by the waves. Oil rigs, just like ice bergs, have a large part that is submerged and invisible on the surface. Look at this for example: https://s-media-cache-ak0.pinimg.com/736x/73/64/d6/7364d6da3...

The problem with a rig is all that vertical structure. It limits where the vessel can be towed to for offloading. To get this rocket off, they need a regular commercial dock.

I'm pretty sure they already flood the ballast tanks for stability.

An even better example of this: https://en.wikipedia.org/wiki/RP_FLIP

That's presumably part of the reason that Blue is planning on using a much heavier ship.

And the second launch with the updated grid fins made out of titanium alloy. Elon Musk said it went well and they want to reuse them indefinitely.

This was the first launch of the titanium fins. The BulgariaSat booster from two days ago was an older block 3 first stage with the "original" aluminum fins. They did glow quite a bit during the very hot re-entry, visible on the last few video frames before the feed cut out: https://youtu.be/Y8mLi-rRTh8?t=1405

That was probably not just glow. That was the shielding material actually burning.

Yes, you're correct. Elon stated in a tweet earlier today that the aluminum fins had burned up their ablative coating on every flight.

I misphrased it. I meant the second launch of the weekend. Not the second launch of the fins.

Your wording makes it sound like there have been two launches with the new grid fins. For clarification, I believe you meant the second of this weekend's launches was the first to use the new grid fins.

To deploy 10 satellites, does the rocket do a series of burns, or do the satellites have enough propulsion to deploy themselves to separate orbits?

The satellites do it themselves. The deployments from second stage are staggered with pauses of 100 seconds between each to allow them to safely drift apart from the initial separation jolt. After that, the sats do their own thing.

The deployment from the dispenser just puts the satellites in the same orbit with a little bit of offset between them, enough for comfort. The satellites then raise their orbits just a hair using their own propulsion and then use phasing to adjust their positioning so that they are equidistant along the orbit. That part takes a long time (hours) but it doesn't require a lot of propulsive capabilities so the satellites do it themselves.

The required propulsion is minimal. They're all going into the same orbit, just spaced around it. A tiny speed difference is enough to do that, since it adds up over time.

Looking forward to articles complaining about SpaceX launching too often. :)

I had always hoped that they would use giant versions of these pin toys to land rockets.


Some mornings when I am unable to get out of bed, such news act as an Adrenaline shot for me. I kick myself out of the black hole and go ahead to launch my rockets (metaphorical).

If Elon can, I need to, as his protege (again metaphorical)

The frequency is quite staggering. Will Musks replace Hertz?

This was only possible since the two launches were on different pads. Otherwise they're on a good path of having one launch every two weeks this year.

And they have quite aggressive goals of 24 hour turnaround on the same pad with the same first stage eventually.

It seems like most missions don't have the fuel budget to return to LZ, so they're going to have to buy a lot more drone ships!

There has been talk of the droneships refueling the landed stages and then them taking off and flying back to the LZ.

It's sounds crazy to me, but so did a rocket launching, splitting in half, then landing 1/2 on a barge in the ocean to be reused while the other half goes to a GTO orbit.

Once Falcon Heavy is flying you could upgrade those flights to FH with a flight profile where you can land all cores on land. The only difference would be more fuel used (which is cheap) and threefold increased risk of stuff going wrong in the first two minutes. May depend on how important it is to get those cores back immediately. Upgrading otherwise expendable flights to FH is already planned as well.

The upgrades of Block 5 later this year will improve reusability and performance, though, so more missions can be RTLS.

If the payload is small enough (compared to FH), will it be possible to SSTO? Then you could park in LEO, and return to LZ when it's clear!

Edit: no. Falcon Heavy has more than one stage.

But it's having goals like that, that gets you there. Remember when the others made fun of re-usable 1st stages? :D

Next year they should be going from two launch facilities to four, though, so if each one takes two weeks to turn around, they could still conceivably maintain an every 3-4-day cadence.

As in our entire development team turned over at 1/2 Musks rate?


Sounds like you got a ragging Elon

Does anyone know why a side-view of the actual touchdown (like they usually release after) hasn't been posted by SpaceX yet?

I'm wondering what would be the flight time for a transcontinental flight on a SpaceX falcon9?

How about London to NY?

wondering if all this tech is only for rockets or he has a plan to build the next generation of "airplanes" for traveling.

I guess from Elon's POV travelling long distances is already fairly efficient with airplanes for people and ships for cargo. As evident from projects like Hyperloop and The Boring Company he tends to tackle the shorter distances where things like trucks, cars, or planes are rather wasteful (and trains seem to be not good enough, but maybe that's also due to the US' bad train infrastructure with virtually no high-speed rail at all).

So, no, I don't see anything like that coming. Based purely on speculation and observation, of course.

> US' bad train infrastructure with virtually no high-speed rail at all

The US has the best train infrastructure in the world. What is lacking is passenger rail, which gives the false impressions that the infrastructure is bad. Trains are not a very good fit for moving people for the most part. Other countries have stretched those limits to the max which means that they can give the impressions of good train infrastructure.

I'm reading his autobiography right now. Fascinating life of both the man and his companies if you are interested: https://www.amazon.com/Elon-Musk-SpaceX-Fantastic-Future/dp/...

That's a biography, not autobiography. And Musk ended up refuting some aspects of the book.

As someone who read the book, do you know which parts he refuted?

Primarily the child care / miss the birth of a son quote, and the fact he called himself a Samurai.


So basically very little.

There seems to be a reason that more companies are not attempting to reuse rockets [1]

So considering that, SpaceX has not proved anything, yet. Because the impossible or hard part is not launching and landing rockets. Hard part is to do it..

1. With same or more reliability than using completely new rockets.

2. Launch with enough frequency to justify the reusing procedure..

So yea. A couple of launches and reuses does not prove anything. It is a start, sure. But they have not yet proved others who didn't attempt this yet..

[1] https://news.ycombinator.com/item?id=14626183

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