That was what killed the Apollo program. People are so quick to adopt new things as ordinary, once they drove around on the moon with a dune buggy, only an accident could have held an audience.
that's what people don't realize though. It isn't about an audience. It's about humanity and us furthering our understanding and exploring the universe
Thanks for taking the time to simulate it for us. There are tons of videos explaining it but this so much better. Also It's craxy living in this technology driven time when someone at home can produce 3 full 3d simulations, create a 30 minute video explaining the failure and then publishing it to a free "television" service for anyone to view it a day or so after the event. Amazing.
I was soooo impressed with what that machine did. It fell from space, had the fin lock up but still managed just before touchdown to stop its rotation, straighten itself out and if there had been solid ground under it I think it might have landed. Those legs came down and it tried it's best to stay up, even on the water! I felt bad for it. They have got to get an "A" for effort and engineering. OK. I guess all you guys nit picking my comment work for SpaceX as engineers who are saying it wouldn't have landed. That wasn't my point. Did you see that thing standing straight up in the water?? It was a relatively controlled landing by a crippled vehicle that fell from space! I'm no less impressed. It was an awesome effort by man/woman and machine! Well done.
It's still rotating quite a bit though, and I'm not sure if it was completely straight. Just a bit of rotation could be enough for the landing legs to break and cause the rocket to fall and go kaboom.
@@Tchofi I had thought just maybe it could have landed. But great point, a bit of rotation would make the landing "feet" catch, kinda stumble sideways, tip it over. Had never considered this - another factor SpaceX has to be nearly perfect on for a successful landing.
It must suck to work for Space Ex if you are a rocket. You get fired on the first day of work and, assuming you do everything right, they make you come back to work *AFTER* being fired. I don't blame this guy for landing in the water. My boss fires me, I ain't coming back.
it's funny, i always thought this was more of a hobby/side-project for you. So i always took the videos for granted. But then i realized how much work you actually put in to your videos, your website, the livestreams and everything else. And yet you still have time to design merch, answer comments, and you even have time to make music! So I just wanted to say THANK YOU for the hard work, and continuing to inspire and educate people from all around the world. Waching your launch livestreams has become almost a routine by now. I even watched the last one with my entire family. Too bad that the first launch they saw didn't include a perfect landing, but hey it was still interesting. SO THANK YOU FOR EVERYTING!!!
A few notes: Yes! Russia doesn’t really use flight termination systems as I mention in that “biggest booms” video! Also, despite just talking about the Falcon Heavy Center core in my last video, I totally forgot we already have seen an engine (or two or three maybe) fail to light!!! I still would love to hear more info on that! And here's the Mission in Kerbal so you can play along too! - steamcommunity.com/sharedfiles/filedetails/?id=1587695886
Hey tim. In one of the debriefing where elon said that Block 5 is now forzen for certification, he also said that non significant changes are allowed. With the addition for a redundant hydraulic pump i would assume it would go to Nasa for their decision on whether it counts as significant or not as it's addition wouldn't have any affect on the vehicle for the primary mission. Nasa's investment in Spacex shows to willingness to innovate and adapt and i'm sure they don't mind the cast savings either.
Everyday Astronaut Hey Tim is it possible that I could message you on Reddit? I'd love to get into a discussion with you about the Falcon 9/Heavy, a little about how they work, and the future of them (how are they gonna get phased out by the BFR) or things like that related to SpaceX
Interesting. This “failure” actually validated the computer control system and how robust it is. See kids, failure isn’t a bad thing. “Successful failure”
@@jmonsted except no. Failure is when you start learning what's best and what's worst you don't keep doing the worst thing from that failure. Just my opinion, don't need to get buthurt
I'm gonna be working on the Blue Origins BE-4 manufacturing factory, and it looks absolutely amazing. Mr. Bezos himself even is excited about it, and if you would like id love to show you around once we start construction. I know this isnt related to the water landing, but its just a thing that I feel like you would be interested.
Thank you for sharing this with us Tim. I just wanted to say that your new album is great, I've played it through many times now. It's a good album to work to, and gets people asking what I'm listening to when I have visitors. Keep up the spectacular work!
Tim, that was the best video I think you've ever done. You're SO GOOD at explaining stuff and it helps me understand how it all works. Keep doing what you're doing my friend! :)
@Felipe Lavratti The first rule of Fight Club is: You do not talk about Fight Club. The second rule of Fight Club is: You do not talk about Fight Club. Fight Club (film), Flight Club (software)
I love pointing out to friends and family just how thin our atmospheric security blanket really is. That google overlay with its tiny boost back loop is just one more thing I can point too lol
I think they do two doglegs. The first is aerodynamic, to keep the ballistic trajectory well away from the landing area and to bleed off speed. They also do a propulsive dog leg so they miss the landing pad (or ship!) if there is a problem with the landing burn.
Yeay, that's exactly what I understood also. Makes much more sense then Tim's explanation since you can't say it's safe all the way down, and also that if the engines don't relight it would hit the LZ
Didn't you mean that they DON'T do a dogleg when there is a problem? The doglegs are performed to change the ballistic trajectory to a new target, the LZ (pad/barge), when everything is nominal, right? You're saying it the other way around I think.
Nah, if the landing burn fails it should crash land at the Landing Zone, think about it, around it there's SpaceX support "buildings" (might be a tent), the water lines for after land cooling, a forest, etc. a slab of concrete is the safest place for it to crash land.
DumbSloth87 I watched some more videos and it looks like they generally don't do a propulsive dog leg on land. That would be one crazy lawn dart game if the engine didn't start! LOL
Thank you for your evergreen content. I watched and liked this when you published it, and again today, and I am still entertained and informed these many months later. Thumbs up again!
RU-vid showed me this older video I hadn't seen before. It's so old I don't remember that rocket landing failure. I've seen Tim talk about the dogleg maneuver in more recent videos, how the landing path initially goes into the ocean and such, but this is The Whole Story right here.
Been following for a while, but here you deserve a huge thumbs up. This video stands out for spot on relevance & timeliness and fantastic approach to getting your points across. Hope it will get you over 200k subs and wish you continued success.
Thanks so much for the reference to the flightclub program! I've been looking for a good model to track paths of rockets for a while now, I know what I'll be doing every launch now!
No joke, Tim, I was driving into work today and thought 'I really hope there's a new Everyday Astronaut video, I could really use one'. Wahooooo! Thanks for everything you do broheim! In a virtual world of garbage, pointless channels, you and yours stand as examples of what the internet could and should be all about. High quality, meaningful entertainment that enriches the mind. Your videos are more than view grabs, they're works of art! Mad respect!
Wow thank you so much!!!!! Jeeeez that really really means a lot. A lot of work goes into these videos, so I'm really glad to hear you appreciate them!
I'm surprised you didn't mention the center core of the falcon heavy. That was a failure of the engine to turn on and what happens when it hits the water at close to terminal velocity.
@@GlanderBrondurg The center engine lit, but the subsequent outer pair did not. Because this was critical for deceleration, the deceleration was about 1/3 of what is necessary.
@@avid0g I realize that, but the engines pumps did start to operated and physically worked. The problem was that they ran out of the hypergolic fluid used to get the flame going inside of the nozzles. Called Triethylborane, this produces a sort of blue-green hue when you seen the engines light up before the RP-1 and LOX start to burn. The center core simply ran out of the TEA-TEB needed to get those other engines running.
@@GlanderBrondurg Yes, I saw Elon Musk's tweet of exactly this, just after the event. Many possible causes come to mind. I expect that the amount of stored TEA/TEB was supposed to be the same in all boosters. Near as I can tell, all boosters were expected to have the same quantity of engine ignition events. Some engine(s) may have completely shut off during "throttle down". That would then require extra engine ignitions in the center core. Perhaps some sensors used to detect propellant combustion were in error, causing a delay in shutting off the "lighter fluid" until a fall-back protocol confirmed thrust. Another possibility is that some center core engine(s) had real ignition problems, causing the TEA/TEB to be consumed for a longer time. In any case, I suspect there was greater-than-expected consumption of TEA/TEB in the center core.
I agree the geometry of the first stage changed when the legs were deployed, and it lost a lot of its spin this way but in addition the extended legs also had a far greater- and better leveraged rotational drag. Good video thanks for the time you took for this one.
Thanks Tim. Even when things don't work perfectly, I still think that the 'Dan Dare'-style vertical landings are amazing. The comic strip was more than 50 years ahead of its time on that feature.
Another great vid Tim, it was cool to see the booster fill up with water on the camera POV behind the presenters during the live broadcast (I tweeted a pic of it @ you a couple days ago)
Impressive explanation of how SpaceX charts a safe landing of their 1st stage boosters! It seems to me that this is an obvious built-in safety factor... i.e. if anything goes wrong, early, the booster will self destruct, if something goes wrong late, the booster will land harmlessly off shore. I am astounded that SpaceX has this level of fail-safe built into their RTL boosters! ... not to mention the fact that it still knew enough to survive the off-course trajectory, so that they could recover the booster, ... and LEARN! Todd, excellent video! Thanks for explaining this. You provide us muggles with a level of detail that most of us couldn't obtain. I have a profound level of trust in the space program, to keep us Floridians safe. I had never considered the fact that these boosters could crash over populated areas, but it's nice to know that this has been heavily factored into their equations! The dog-leg maneuver is clearly a built in fail-safe. It is built into the flight plan, as a late maneuver, only when everything is nominal. I never knew this existed. The booster is targeted for the ocean until very late in its landing sequence, then must aggressively target it's landing zone. Thanks for explaining this!
One thing you are missing is that an explosion high up in the atmosphere will produce lots of shrapnel, but it will have time to get to terminal velocity, which for shrapnel is pretty small. For an explosion that is a few km above the ground, the shrapnel could still be more energetic then the terminal velocity, which could cause a fair bit of harm. Thus, activating the FTS close to the ground is actually more dangerous then just letting it hit the ground. In addition, as you said, it can't move very much, to the point where it could hit anything important.
You ramble just as much as you like.... its all full of good information. PS: Did you notice how the grid fins extended... they folded out in steps. Is that normal?
I think not only the legs kill rotation, but the gridfins has no speed and no airflow, witch make them rotate booster. So on the last few seconds stage almost stop and that's make rotation unable in case of aerodynamic. Nice video, buddy. I like it.
Stopping the roll was done by a combination of several factors. Coupling of the axis of movement gave the main engine the possibility to cancel some of it (some roll energy was transferred when it tips over, and that's something the main engine can cancel and therefore bleed off energy). Lower speed gives the grid fins less bite (as you point out they still have an effect, just not as much). This in turn would give the RCS more authority to cancel the roll (although I'm not 100% sure they still had gas left at this point). The legs coming out would as you say reduce the roll due to conservation of angular momentum, but they also create some air drag that helps slow it. The little roll that was left was then canceled by the legs hitting the water.
I wouldn't be surprised if they had a static bias on those grid fins that the pump has to actively cancel in order to maintain no-roll flight. Think a spring between the grid fins that's trying to turn them out of alignment. In that setup, a loss of the pump would force the booster into a spin stabilized ballistic trajectory no matter what state it was in when the pump failed. From a design perspective, that meets all of the criteria for a solid approach when you add the dog-leg maneuver into the mix. It's able to handle unexpected situations well, it's reliable, and it's light. The simplicity of it is icing on the cake. There's probably something similar in place in case of full-blown flight computer failure. In KSP, you could simulate that with a bit of trim on roll, although I'm not sure the SAS would know what to do with that. It'd probably need to be a manual landing.
Tim, I'm not so sure it lacked the ability to reach the LZ. The engine would have massive authority as far as determining the attitude of the vehicle as well as accelerating it in any required direction. The only thing it cannot control is the roll. However as long as the rolling is not fast enough to break up the structure or confound the inertial platform it should in theory still be able to reach the LZ as the nozzle can still be kept pointed in any required direction despite the roll. This can in fact be seen in the on board video where the plume appears to be spinning around relative to the rocket body but from the ground video we can see it is exactly cancelling out the rotation and pointing in a steady direction relative to earth. I think the reason it landed in the sea rather than on LZ1 may be more due to an abundance of caution rather than a lack of capability. Safety considerations aside would probably still have estimated that if it was not entirely stable during touchdown it might have a better chance of survival impacting the water rather than soild ground.
Amazing video as always! One quick comment, a fact I learned from one of your previous videos actually, the first stage apogee is under 100km (I think you said 65km) so it technically it never exits the atmosphere and so there's nothing to *RE* enter.
@@EverydayAstronaut sorry about the autocorrect error, that was embarrassing. Fixed it now. And, oh ok, I must have misheard then. But regardless it looks as if it's already within the atmosphere by the time that burn happens no? Isn't a reentry burn a burn intended to cause reentry? Like if I were coming back from the space station and had put enough distance between myself and it, the next maneuver would be a reentry burn to return myself to earth. I could be wrong though.
@@EverydayAstronaut oh also, on a slightly different note, I wonder if the the engine gimbals use the same hydraulic system. Likely not based on Elon's response to Scott Manley's tweet, but if it is that would probably give nasa cause for concern.
Great presentation. The only nit I might pick is with your comment that NASA doesn't care about the booster landing. Although it is a commercial endeavor by SpaceX, and it's not necessarily within the scope of NASA's mission, they certainly have skin in the game, as a worst case catastrophic failure could possibly result in damage to KSC property/equipment or (heaven forbid) injury/death of unsuspecting personnel in the vicinity. All it would take is one such event and NASA would likely pull the plug on any further landings at their facilities. Steve
The call out that the AFTS - the *automatic* flight termination system is deactive, however I think the range safety officer had his hand *very* close to the manual FTS button during this failure. He had to make sure in split second that the booster doesn't crash anywhere where it isn't supposed to. After all the 1st stage IS capable of targeting land after the entry burn (so after the AFTS is disabled) all by itself since this is what it does during a normal landing. Theoretically the gridfins could be stuck in a position where it would hit land but not on the pad.
Given the circumstances though, exploding the rocket that close to the ground is likely to cause more damage than keeping the rocket in once piece. Going up, it already has momentum to push all of the parts away from each other and it is going to end up in the middle of the ocean for every piece too. Coming back down, all of that shrapnel will be more or less landing at the same spot and will guarantee a hit of something onto anything in that general radius with a destruction of the vehicle.
the AFTS is safed after the reentry burn because at that point momentum and atmospheric physics calculations say that the rocket could not possibly reach any civilian area. the balistic trajectory is the centre of that area, or cone as tim called it. and the landing zone is near the edge of where the rocket could possibly reach. there for the need for AFTS, like RedPuma90 said, the explosion would more likely be dangerous from flying shrapnel
It could not hit land if it is spinning, no matter where the gridfins are. It would follow a spiral around ballistic as lift rotates round, and lift would rotate as the axis of rotation precesses around the direction of travel. The RCS system is capable of setting up such a spin, even if the gridfins are not spinning it up. We didn't see this here, as it was already spinning, but a "grid fins jammed" mode could be deliberately spun up to avoid any possibility of it hitting land.
I would say there are three things that dissipate the rotation. The RCS thrusters were controlling. The moment of inertia change and also the grid fins angle of attack change due to smaller speed dampens the rotation. It can only rotate to certain roll rate in the certain altitude and at certain speed so I would say that this was the case. I think the grid fins were accelerating the rotation but at landing decelerating the rotation
