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.
[EDIT] fixed typo
When Apollo got boring, they lost funding. SpaceX has a waiting list of customers.
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.
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.
Apollo 11 was a huge event, but by Apollo 13 none of the networks carried it.
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?
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, isn't it the oldest trick in the pr/advertisement process. To create an impression without actually claiming anything.
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.
(X) reusable vector
(_) non reusable vector
Technicalities of the hows doesn't change that reusing stuff was already done extensively
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.
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...
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.
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?
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..
> Rocket is extra toasty and hit the deck hard (used almost all of the emergency crush core), but otherwise good
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.
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.
> Flying with larger & significantly upgraded hypersonic grid fins. Single piece cast & cut titanium. Can take reentry heat with no shielding.
They're amazingly deliberate in how they mingle bleeding edge R&D and commercial activity. Something that fascinates me. And rockets.
2nd Thought: By that time, space would already be too junked. Better to use public transport.
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.
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.
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.
So time will tell. :)
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.
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 still want to see them though.
Chutes have to be repacked, means it's a no-go. Powered landing is where it's at for true reusability.
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.
Every single thing they're doing in this program is prep for Mars.
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.
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.
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.
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.
Long term, the only viable competitors of SpaceX include Ariane and Blue Origin.
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.
Blue Origin prices are unknown so far.
Around 60 vs. 62 million.
And you get an order of magnitude better reliability.
This might change in the next years, but for now, it's not changing.
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.
That's not true, usually a day or two after the landing Elon or SpaceX post the footage to Instagram and then later to YouTube.
The man in charge of this (/u/bencredible on reddit) has also explicitly stated that it's not intentional.
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.
Maybe you haven't seen some of the earlier ones that had RUD. Take this 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.
Adding a successful one. See how the rocket comes in, pointing away from the barge and then straightens up.
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.
It's not about withholding the footage, it's about releasing it in a controlled fashion.
Now do it on a boat, trying to compensate for waves and exhaust gases from a 27.4 tonne rocket.