I love that the launch and subsequent landing of a reused first stage is so unexciting that this article has no comments an hour in. It's truly impressive how quickly SpaceX went from experimental landings to boring and routine landings.
When technology like this reaches the point where it becomes unexciting for most people it's when I feel the most excited. It's no longer "one day into the future experiments" but "I now live in the future".
Well if we're searching for interest, a "first" for this one was that this was the first rocket that has landed on two different oceans. The first launch was from Vandenberg and landed in the Pacific. The second was from Cape Canaveral and landed in the Atlantic.
It's the first single orbital booster to have been launched from two sites actually, much less landed. The shuttle almost made it to a second launch site and would have been first here until they killed the Vandenberg pad after Challenger.
Landing the second stage is gonna be Hard. That's Hard in the sense that landing the first stage was Easy.
There were a lot of complex challenges about landing the first stage, but nothing that seemed impossible. Figuring out how to control a spent first stage with almost-empty fuel tanks while falling through the atmosphere at supersonic speed and firing a rocket backwards was surely tough. Getting the control systems right to land that stage lightly on a ship when you're almost out of fuel and have too much thrust to hover is also tough. There's no reason to think that either one should be insurmountable though. If you have the budget and the will to run some experiments and trash some hardware, you should be able to figure it out, and SpaceX had and did.
Now for the second stage, there's a fundamentally harder problem of how to slow down the second stage from orbital velocity without making it so heavy to defeat the purpose. I haven't heard any good ideas on that yet.
SpaceX has rather different economics from most of the rest of the aerospace industry - they aren't getting any super-lucrative Government contracts, and depend on making a profit on fixed-price launches to stay alive. They don't need a ton of good PR or political will, as they're depending on the size of their invoices for launches compared to the competition doing their work for them. If I was them, I'd focus like 90% of my spare engineering effort on optimizing the first-stage recovery and relaunch process as much as possible for now. They've proven it can work, and now they gotta make it fast and cheap. This will bring in boatloads of cash to get the company in better shape and help them corner the launch market. Once they've optimized the first-stage reuse process, then they can really focus effort on looking for a way to recover second stages.
They're looking at experimenting with that on the payload-less Falcon Heavy test flight. For operational use, the payload penalty of the extra mass on a second stage is sufficiently high that it seems likely that only on FH flights (and not even all of them) would they have the possibility.
It incredibly expensive, a satellite that could be lift by a Falcon 9 with a first stage only recovery would have to be lifted by a Falcon Heavy if you wanted to recover the second stage. Basically you'd need to almost double the unfueled weight of the second stage with aerodynamic devices that can withstand the re-entry plasma and the heat shield. And then add the extra weight for the de-orbit and re-entry burns. You would probably more than halve the payload capacity. Even at best is borders on not worth it.
Interestingly, now that SpaceX has the X-37 contract, there is the possibility of launching and recovering a re-used first stage and payload, but not the second stage! I guess this almost happened with the Dragon that contained a re-used pressure vessel, but not-quite.
The Apollo program was a money sink because it was an experimental project based entirely on untested technology and subjected to very tight time constraints, whose client was willing to paying a premium to get the results he ordered in record time.
SpaceX doesn't have to deal with many of those constraints, and the project needs to be profitable in order to get the program running. Consequently, while the Apollo program design in a 10-year timespan about four launch vehicles, rebuilt from scratch about two dozen launch vehicles and conducted over a dozen manned flight missions to the moon, after nearly two decades of existence SpaceX is being lauded for using a rocket more than once.
Requirements are different. Therefore, planning is different and results are also different.
I would guess each Apollo was a profit for Boeing, North American, and Douglas, too, but that doesn't matter.
SpaceX has indicated that it wants to be more than a way cheaper way to launch stuff into orbit. That means it needs to find sponsors willing to spend lots of money, and keep them interested for a long time. If new tricks like reusing a rocket soon become "meh", that means it needs many such tricks.
Haha, yeah, not really any big deal. I mean they're only the only company among all companies and/or nation states with launch capabilities who have ever done it in the history of space travel.
There are plenty of companies who are the only company that manage to do something ever in the history of something.
For example Boston Dynamics had an autonomous robotic mule that can travel pretty much through any terrain. How awesome is that? Yet, that doesn't make the evening news, does it?
In this case, SpaceX is a company that managed to reuse the same equipment to try to cut their operational costs. Well, that's neat and all, but do you understand why no one stays up late at night to watch this sort of stuff happen live? Or at all?
"no one" is a bit strong when Hacker News has multiple people who stay up late a night to watch this kind of stuff happen live -- see all of the complaints about Elon fanboys over the years?
They discarded the fuel tank, and the SRBs landing in the ocean required a dive team and significant refurbishment before they could be reused. Even the shuttle itself required significant refurbishment before it could be reused.
I mean yes it can be, but this isn't really an instance of that. What SpaceX has done is create a reusable booster which lands using retrograde rockets. This is a big deal because with retrograde rockets you can land the thing with precision and upright. Whereas with parachutes you'd end up having a high probability that the rocket would land in a precarious position because it's then at the mercy of the wind much more than the retrograde landing is.
It's kinda like well no Henry Ford didn't invent the car, but he made the car affordable. Heck he didn't even invent the assembly line but he sure did use it in a different way.
Elon is doing to the rocket industry what Ford did to the car industry. Making it more accessible.
What, exactly, do you think is a reusable rocket? You can't just land it, refuel, attach it to a second stage, and fire it up again. Everything has to be retested and tons of stuff replaced because the forces during launch, let alone reentry, are extreme. Until they have lots of data on failure modes in the reusable stage, they are probably ultraconservative with what parts they replace so I wouldn't be surprised if the cost of reuse is ~40-50% of the cost of a new one (on mobile so I'm too lazy to look up spaceX's official numbers).
SpaceX's stated goal is exactly that - turning spacecraft into something more like a commercial airliner. Quick inspection, refuel, send it up again within 24 hours.
The Shuttle threw away its fuel tank, dropped its SRBs into corrosive salt water, and needed all 35,000 tiles inspected every time. The SSMEs needed a full removal and rebuild.
SpaceX has deliberately gone with multiple, redundant, lower-performance engines that are easier to maintain and less sensitive to the forces of launch and re-entry. More like a Toyota Corolla versus the Space Shuttle's F1 racecar - and every generation of the Falcon (there've been five so far) incorporates lessons learned to make it more rapidly reusable.
> I mean they're only the only company among all companies and/or nation states with launch capabilities who have ever done it in the history of space travel.
That assumes all of them were trying to do it all this time, and were failing all the time, which is not true.
I mean, we had control systems in missiles that could track a jet that is doing evasive maneuverer while going as fast as a bullet..like what? half a century ago?
Seriously. i don't think landing a small rocket on a barge comes anywhere close to that...
Note the reusable part. That sort of tracking is much easier if you don't need to resuse the hardware afterwards.
Anyway, anyone else who wants to be able to compete with SpaceX on price is going to need to start doing this before too long, so we'll see how difficult it is.
> That sort of tracking is much easier if you don't need to resuse the hardware afterwards.
Says who?
Your tracking is either precise or it is not. What you are using the precision for is immaterial in this regard..
>anyone else who wants to be able to compete with SpaceX on price is going to need to start doing this before too long, so we'll see how difficult it is.
Wait a minute. Are you seriously calming that spacex is the only company that have landed a rocket successfully?
Imron said "compete with SpaceX". I don't follow developments real closely, so could easily have missed something. Can you point me to any other company which has landed a rocket after putting a payload in orbit? Because if they aren't deploying payloads, they aren't competing with SpaceX.
(Yes, NASA and Bezos have landed rockets, but only straight up & straight down. Nothing close to orbital velocity.)
Note that the Falcon 9 first stage is not travelling at orbital velocity, or even that near it really. At separation time -- when it starts to slow down to re-enter -- "[f]or a reusable Falcon 9, [speed] is around Mach 6, depending on the mission." (Quoting Elon Musk, the SpaceX CEO, on Twitter.)
>Can you point me to any other company which has landed a rocket after putting a payload in orbit? Because if they aren't deploying payloads, they aren't competing with SpaceX.
Alright then. It might be true no one else had done this. but take a look at this, which might explain why no one else is doing it..
If you rewatch the live stream, at 31:45 or so the rocket starts hitting the atmosphere at 6500 km/h, or nearly 2 km/s. The grid fin, used to help steer through the atmosphere is burning, and then the video from that rocket cut out.
At that point I simply presumed it was over for it, yet somehow it still managed to land. They'll probably use it again. We live in a crazy, amazing world.
> The grid fin, used to help steer through the atmosphere is burning
They're using ablative paint, so that's somewhat intended. It's needed because the current fins are made of aluminium, they intend to replace them with titanium ones in the future which will have improved reusability.
There's a decent chance that they might not. They've been making more and more improvements to Falcon 9 in later blocks. In particular there's been an effort to improve reusability of the later designs. Currently SpaceX is having more and more used Falcon 9s piling up. Who knows for sure, but at the moment they have no shortage of reused rockets and it's preferable to them to start using the later designs.
If they're faced with a low probability landing scenario, such as the fastest re-entry velocity to date, and they need to "test" their control algorithms, which first stage would they choose? A near end-of-life used booster or a late block booster from which they would hope to get another several good launches? - assuming all others characteristics support the current launch parameters.
They're amazingly deliberate in how they mingle bleeding edge R&D and commercial activity. Something that fascinates me. And rockets.
If you watched live the video of the landing was very patchy. In fact there was just one frame before the rocket landed and it showed the empty barge deck but a huge depression in the surface of the ocean on the other side of the barge and there was an instant and loud in take of breath by the SpaceX crowd.
It really didn't look good, either the rocket had gone into the ocean there or the rocket somehow had hovered over that spot far from its expected landing zone. The video stopped again for what seemed like a long time might have been 30 seconds the next single frame showed the rocket far off center on the barge deck and there was a huge cheer from the SpaceX crew. It must have been a very close call.
I too found that particular set of frames quite interesting. So the last telemetry had stage 1 at 5700 km/sec and 22.3 km in altitude (so about 13 seconds from impact). The landing burn starts and at 24:55 "something" impacts the water really hard next to the barge. The announcer calls "landing burn has started" but you don't see any change in the telemetry (altitude or velocity) so its safe to say the downlink is still not functioning at that point). Then at 25:41 (about a minute later) we see the stage sitting on the drone ship. So once again I'm really surprised they haven't figured done something to stabilize video. Even it it were a 'drone dinghy' 500 yards off to the side holding a steady lock on a satellite or an aerial drone.
The other interesting bit is at 23:42 where we see one of the grid fins in the process of burning off the side of the rocket. Then we lose downlink video from that point on with the stage. It is flying at nearly 4,000 mph at an altitude of 87,000 feet. The SR-71 goes half that fast at that altitude and experiences significant heating on its skin, since drag is proportional to the square of the velocity you're taking 4x the heating.
It has to be a very fine line between burning these things up vs landing them. And clearly the more 'abuse' they will tolerate during re-entry the more fuel you can use toward lift mass. Still, I'm always surprised that they don't use more rocket power to slow down while above 100,000' to avoid the high speed re-entry and then use streamers or drogue chutes rather than RP1 to slow down in the thicker atmosphere.
From what I picked up, their fuel budget for the landing was borderline, as this satellite mission didn't leave them much. This means, they had to go in very fast, and also use a 3 engine landing burn instead of the usual 1 engine. So it was more a test whether they still can land the rocket rather than a proper landing. For that, it performed well.
Yup. And Elon had queued up that exact talking point roughly 3 hours before the launch. However, having watched this company for a while and Elon in particular, he is much more nuanced in what he says. All through SpaceX's life they have leveraged the customers expectations in order to do their own R&D on the customer's nickel. So when they weren't bringing back rockets they charged for the cost of the rocket and then on the now 'waste' rocket invested in using it to test recovery systems of various kinds. Losing the test vehicles is not a problem its cost was covered by the launch. Now that they have some pretty good understanding of recovery, they use 'flight proven' boosters as their test vehicles, bringing them in under different flight regimes using different recovery parameters. I really think it is a brilliant strategy and one that I admire. What I think about is if I was working for them the even more stuff I'd be doing to get even more data from the tests. (like a better video recovery system, which truth be told they very well may have, after all they are under no obligation to show us and their potential competitors what they are trying to improve and what they don't know)
I can't tell by your wording, and I was similarly confused about their video recovery system, so maybe this will be helpful for you.
The only thing SpaceX hasn't invested in is a better downlink. The video is fully recorded and stored on OCISLY, so they will analyze and post later.
The rocket merely interrupts the realtime feed.
Which leads me to believe SpaceX just doesn't care about a robust realtime feed since they can analyze offline -- or they just don't care about one for the public.
Given that the downlink is reasonably stable when OCISLY is just sitting there (with our without a booster sitting on it) I'd love to see them back up on the locally recorded video and then send it via the downlink once the link has restabilized. We're talking about 18 seconds of video here, not hours :-)
I would be interested to hear how SpaceX internally views sharing video with the public. I could imagine a range of feelings from "why waste time showing them" to "an essential part of our marketing and outreach." I personally see it as fascinating stuff that touches on so many interesting questions about rocket design, future space feasibility, and the design limits around cost optimization.
> The video is fully recorded and stored on OCISLY, so they will analyze and post later.
Can you link to any posted-later videos of landings? They pretty consistently either drop frames or cut out entirely on the live stream around the moment of touchdown, so it'd be great to see decent quality footage of some landings.
I mean, it's not like a really robust realtime feed would be much help for them anyway. As far as I know the rocket is completely autonomous, so even if something was going wrong during the landing a higher-quality feed would just give them higher-quality reasons to tear their hair out etc.
I disagree with this. Having diagnosed a number of problems in nominally 'autonomous' robots through the use of video. There are also instances of many issues being diagnosed by video, consider the loss of protection tiles on Columbia which was diagnosed (or at least confirmed) by watching video of the lift-off.
That said, SpaceX has a phenomenal number of video feeds and I really enjoy them. Early in the Falcon 9 project we would see on the web cast a cut to a video shot with no explanation of what it was, but we know now that they were looking a fuel settling and other effects during re-entry.
And yes, given that you can learn a lot from said videos about how it is done, and there is at least one high profile (Blue Origin) and a no doubt a number of low profile efforts on going to duplicate what SpaceX can do, there is some competitive advantage from not sharing all the video they have.
I'm not saying that video wouldn't be helpful, just that realtime video wouldn't be helpful. They surely record the video for later analysis as others have mentioned.
Unless they want to, you know, analyse the landing before they launch another rocket two days later :-) . But of course that doesn't require realtime, just the ability to download via satellite while drone ship is on the move.
Even the lightest wind is also hell on a targeted landing. Our model rocket experiments clearly demonstrate a significant force is applied with even the lightest winds which ends up putting the rocket far off course when choosing landing zones.
We have actually been precalculating trajectories, and have used trial balloons to measure wind speed and direction immediately prior to launches, combined with planned pre-flight path alterations in an effort to land rockets with parachutes more accurately into a targeted area or small designated area.
Not just SpaceX, everything Elon is doing is centered around mars. Yes some of these are a stretch, a big stretch even. Ok a ludicrous stretch. Anyways by company.
SpaceX-pushing rocket tech makes mars a more targetable endevour.
Tesla- better solar panels and better batteries mean you can consume and store more power on be red planet.
Open AI- it's going to be very important to be able to prefab critical systems before any astronauts get there. AI can help there.
Boring Company- Where do you build a home in a place with almost no atmosphere to shield you from radiation? Underground. What's nice and cylindrical and would fit nicely in a tube atop a rocket? Bore segments. Also TBC's bores are being designed with a smaller diameter than your typical bore. Elon says it's so cars can fit in them to revolutionize the LA commute, I see something that can be moduralized and put on top of a heavy lift rocket and used to prefab Martian living quarters.
You have to replace the shock adsorber anyway, the chutes could be as well detachable and replaceable with a ready to go packed one, while the spents are sent back for repacking
From my understanding, the type of parachutes necessary for this, and the associated hardware needed for their safe deployment, are quite heavy and complicated.
I think chutes big enough to save a worthwhile amount of landing fuel would make the vehicle too vulnerable to unpredictable lateral translation due to wind and variable aero braking. That would necessitate using more fuel or bigger and heavier control surfaces to correct for lateral motion. It just doesn't work out.
Also the braking burn just above the atmosphere is already a long high thrust burn. They run three engines for quite awhile at a time when the vehicle has more fuel in it than during landing, which is a single engine burn. Extending that three engine burn significantly would require a lot of extra fuel and as we can see from this landing it isn't needed.
I read that for reusable rocket any chutes increased the start mass and the initial drag to the point making the whole setup infeasible.
Witness Russia tries to design such things. Since about 1985 I read articles about adding small wings and chutes to the first stage of various proposed rockets. Nothing came from that so far.
Me too. And we were talking about the slow obscuring of the video and one thought was that it was stuff coming off the rocket covering the lens but a better explanation is that the lens or other material protecting the camera from the outside was melting. If that is the case we'll need sapphire lens covers for future video streams.
Serious question, and maybe this is more for r/askengineers, but why was so much failure tolerated to successfully land a rocket upright? Is it feasible to land a rocket on its side?
Take a soda can, glue a lead weight to the bottom. Now scale it up to 15 stories tall. You have roughly the design of the Falcon 9 first stage.
As mentioned, it's designed to take stress in one direction, when empty the vast majority of the weight is in the engines, which will make it want to fall bottom first anyway.
It's not designed as a lifting body, so doing things like attaching wings would require additional reenforcement. For each 5KG you add for landing/recovery equipment/structure, you take 1KG off the maximum payload
The upright landing, landing legs, and grid fins is the most efficient trade-off they've been able to come up with so far.
These rockets are designed to handle longitudinal stress, not transverse stress. Making a rocket able to survive hitting the ground sideways would add way too much weight.
They've stated in the past that the reused rockets are offered at a 10% discount, of a launch price of around 60 million. But that's expected to widen considerably, for now there's basically no competition and they're still ramping up production and launch capabilities (and are wanting to recoup their investment).
Don't forget that customers get bumped used in the schedule by quite a bit by agreeing to ride a re used rocket. The extra income from having a sat in space early is much more valuable.
At the moment people are wary of putting payload on a reused rocket. There will soon come a tipping point of being wary of using a rocket that hasn't been flown before.
But that will take a long time, even with new Falcon 9 rockets, SpaceX is an order of magnitude less reliable than Ariane, for now. At exactly the same price.
Long term, the only viable competitors of SpaceX include Ariane and Blue Origin.
Ariane is already not competitive at the moment, and the reliable is not that different. Look at the insurance premium and its clear that the estimated reliability is not that large. They have massively exhilarated Ariane 6 because they know they simply can not compete with the Ariane 5.
Also Ariane is only a viable competitor because they don't need to compete on cost. If Arianespace had to finance the Ariane 6 by themselves they would not be close to competing with SpaceX.
Interestingly enough, if you look at the Ariane manifest you can see that they're having a hard time finding satellites to fly in the "lower berth". Meanwhile, SpaceX's comsat launches are mostly heavier sats that won't fit into the "lower berth".
Yes, it’s especially interesting how basically all of the smaller satellite launches have moved to the – at the moment – more expensive and less reliable SpaceX, leaving Ariane without small satellites to launch.
I'm curious if that discount offsets the increased insurance premiums on the payload(s). Given the increased risk (2/2 successful launches doesn't mean much in the bigger scheme of things) it seems to me that insurance providers wouldn't be keen on insuring such payloads when it's already the riskiest part of the payload's lifetime (with an average 7% failure rate).
SES said the insurance of SES-10 cost the same as on a never flown booster. The Falcon 9 (all versions) is currently 33.5/36, and as long as SpaceX never repeat the same cause for the loss of payload, the insurers don't mind flight proven boosters.
It's a shame SpaceX never/rarely releases any of the onboard footage from the droneship. I understand that the live connection cuts out when a rocket comes down with it's engines on full thrust pointed right down at the ship, but surely the cameras on the ship store the footage.
Since the landing was a particularly difficult and rough one, I'd love to see HD footage of the rocket coming in and landing on the deck of the ship.
Not always, but I would say in cases like this when it's interesting (hot landing) Elon normally does come through with the goods on Instagram/Twitter.
"Seems that @SpaceX often suspiciously "looses" the live video feed of landings until after success/internal review. https://youtu.be/Y8mLi-rRTh8?t=1520 "
Or you know... maintaining a high bandwidth satellite link on a barge in the ocean with three rocket engines pounding down on it is difficult and not particularly high priority. They have never not shared footage afterwards, and we've got footage all the way down live once or twice (not with a three engine landing burn mind you, since this is the first time they tried that).
The man in charge of this (/u/bencredible on reddit) has also explicitly stated that it's not intentional.
It's always been the dodgiest landings that "accidentally" lose video coverage for the longest. I don't believe this explanation, even if it's the official account. No big criticism though; I'm super happy that they do the launch webcasts. Super exciting to watch.
The barge are in the middle of the ocean and need a satellite link to communicate. Satellite antennas need good alignment and it's logical that the worst landings would also be the ones which perturbate the alignment the most, causing the longest video feed loss. There's an explanation that does not involve nefarious intent.
> It's always been the dodgiest landings that "accidentally" lose video coverage for the longest.
A dodgy SpaceX landing means a) ship and b) three engine burn.
The ship feeds have always been sensitive to vibration - they've cut out every single time - and three engines makes significantly more vibration.
You can conspiracy theorize if you want, but it's a bit like complaining that there are more photos of the outside of the White House than the inside of the President's secret bunker.
>It's always been the dodgiest landings that "accidentally" lose video coverage for the longest.
Maybe you haven't seen some of the earlier ones that had RUD. Take this[1] one for instance from the SpaceX channel. Looks like they stopped using helicopters to stream the landing. Makes sense, because once you have all the kinks worked out, you no longer need redundant instrumentation.
In those cases the helicopter recording is by NASA since those are CRS flights. The commercial customers don't particularly care about the landing (apart from cost reductions), or at least not that much, and SpaceX themselves only have the barge and support ships out on the ocean.
It does look like there's a "PR filter" in the video stream and it kicks in when the landing looks iff-ish.
This makes perfect sense too if you think about it. If they were to crash yesterday and there were a video cap to go with it, it would've been all over news in no time. But with no visuals the news like this are far less likely to be reported, leave alone to go viral.
This is tinfoil hat nonsense. The feed goes out for a couple of seconds due to the vibrations caused by the incoming 10-story booster retropropulsing its way to the deck. It always comes back after the rocket has shutdown.
