First Falcon 9 Landing Failure in 267 Launches

it's happened after so many years and over 200 successes a SpaceX Falcon 9 booster has failed to land how could that be what could have happened will this impact upcoming flights will Falcon 9 be grounded by the FAA spoiler alert we asked and we got an answer in this video we'll be diving into all of that and more to try and figure out what on Earth happened last night in the North Atlantic including something that some of you might have thought of in the back of your mind is Falcon 9 reaching its reliability limit [Music] very early on Wednesday morning that's August 28th 2024 SpaceX launched the starlink group 8-6 Mission from space launch complex 40 in Florida on board with 21 starlink satellites including 13 direct to sell starlinks it was your typical run-of the male starlink mission right in the middle of the night that probably definit Ely some of you don't even bother to watch anymore including me I was asleep when this happened this was in fact the 188th Falcon 9 launch dedicated to the staric constellation the only remarkable thing from this mission was the booster itself this booster b162 was flying for a 23rd time becoming the first booster to fly that many times the booster has quite a history having launched pioneering private human space flight missions such as inspiration 4 and Axion 1 it holds the record as the booster with the fastest turnaround time in approximately 21 days and although this happened over 2 years ago it still hasn't been beaten since it was quite a story booster just like with any starlink launch the launch portion for the booster on this Mission went as we would have expected we saw the liftoff of Falcon 9 with a beautiful Ascent then moo meaning main engine cut off and a successful separation of the second stage we then saw the entry burn and the booster steering itself towards the Drone ship as we always see on the staric missions but then at the Landing things went differently while the landing Burns seemed to start just as usual shortly after touchdown we saw a lot of flames on the Drone ship what appears to be one of the landing leg struts snapping and then the booster tips over and blows up that is obviously when the standard operating procedure ends that's not normal for a falcon 9 booster shortly after the landing anomaly SpaceX posted a statement on social media saying quote after a successful asent falcon 9's first stage booster tipped over following touchdown on the a shortfall of Gravitas drone ship teams are assessing the booster's flight data and status this was the booster's 23rd launch so given all of that what else might have happened well of course everything we can see from spacex's live stream is nowhere near the amount of accurate and precise data that SpaceX Engineers have at their disposal when investigating this incident that being said it's always interesting to use that very limited data and previous experience to get an idea of where things might have gone wrong there's multiple things with the booster that if they fail at the right time the outcome could be very similar to what we've just seen for the purposes of this analysis we'll look at these potential points of failure the center engine fails or underperforms at the end of The Landing burn resulting in a hard Landing a landing leg collapses as the landing happens and causes damage to the booster and subsequent tip over or the sea is so rough it causes the booster to slam into the Drone ship with a higher Landing Force than plan which then causes the damage and tip over that we see let's first look at the first possibility which is that the landing burn failed at the end or cut off early for a Telemetry comparison we're taking a look at the previous starlink group 8 mission from the cape starlink Group 8-3 which launched on August 10th that should give us a good approximation of what the Telemetry should have been on today's Mission as the same group launches are usually very similar to each other because they're delivering the same payload to a similar orbit but why are we looking at the well if we saw something very out of order there we would be able to easily tell if the landing B went a skew let's trace it all the way back to Moo for the 8-3 mission Falcon 99's first stage was traveling at a speed of 8,049 km per hour at 64 km in altitude whereas for today's Mission these numbers were a tad bit lower but not by that much with a speed of 8,16 km per hour and an altitude of 63.7 KM this is pretty much on par with what we'd expect for a mission of this kind an earlier Mission Starling group 8-9 launched in July from Florida and had a lower speed and altitude at moo than these two missions in that case though the rocket was carrying just 20 and not 21 Starling satellites so it didn't need as much performance from the first stage given this it's safe to assume that if there was an underperformance on this Mission it did not happen during the ascent portion as the two missions hit very similar moo speeds and altitudes and one had a nominal landing and the other didn't a similar thing happened if One Compares the speed and altitude before and after the entry burn while there's some slight differences these are within the numbers that we've seen for prior booster entries and at the end of the day there's always slight differences between Starling missions so it doesn't seem like this was another point where a failure may have happened this means we have to look beyond the entry burn and go straight to the landing burn one important thing to point out is that the Telemetry is always running ahead of the landing video because it takes less time for text data to reach SpaceX mission control and then get displayed on the webcast we don't know how large spacex's Telemetry packets are but they'll be smaller than a live video for example YouTube recommends for a HD live stream 1.25 megabytes of data per second the video stream will also have a buffer built up of a few seconds which means that the video will always be a little bit behind real time in order to make up for any hiccups in the signal that means that what happens with the Telemetry animation is what is about to happen on the video for example we can always see the start of the landing burn first on the Telemetry represented as a sudden decrease in the booster speed followed by the video of said Landing burn so with that note out of the way let's take a look at that Landing burn if we look at the right when the altitude switches to 1 km above the deck we can even see that today's mission was slower than the previous mission of group eight honestly at this point everything seemed quite normal still but a few seconds later we finally got our first clue of where it might have gone wrong because of the video delay in order to interpret when the touchdown takes place we've got to take a look at when the speed makes a jump since that is when the booster goes from having some landing speed to just stopping on the deck of the Drone ship the prior group eight mission had a touchdown speed closer to 10 km/ hour and then we can see it jump down to 2 km/ hour as the booster settles on the deck of the Drone ship going to an even earlier group eight mission we can see a similar touchdown speed and we even see the speed going back up again before fully going down to zero this may have been due to the Boost of bouncing a little bit after landing as we can then see from the flex on the legs via the video feed so what does the Telemetry for this Landing look like well it appears that there's a sudden jump from 30 km/ hour to about 10 or 11 km/ hour which could either be an error in the Telemetry or it could indicate that this is the touchdown speed this is about three times faster than we've seen on previous missions doing some quick physics we know that a touchdown speed Three Times Higher means an impact energy nine times stronger this could explain the collapsing Landing leg that we can see here in the background a hard Landing could also break the nozzles the OCTA web structure and many other pieces of piping that would explain the fire that erupts right after touchdown we've seen some Fires at the business end of Falcon 9 after touchdown before and it is quite normal as the engines flame out after the end of The Landing burn but I'm sure you can agree with me that this was a whole lot more fire than we've seen on previous Landings of course we do not know the design limit of the landing legs and it could be that this is not even pushing them to their limit but by the Visual Evidence The Landing egg failed so a high speed and high energy load might be the reasonable explanation for that so this might indicate that the landing burn did not go entirely to plan towards the end but if so what could have caused this this might sound silly as the obvious answer could be well the engine failed but did it this booster was quite old it had flown 22 times before this was its 23rd Mission and we know from SpaceX that Merlin engines have in fact launched more times than the boosters have as these can be moved from one airframe to another and fly more than the booster they're installed on so sure that seems like the easy answer an alternative to this could have been that the engine ran out of propellant right at the end of the burn we've seen an extreme example of this in the early days of Falcon Landings with booster b1024 this booster launched a pair of geost station communication satellites all the way back in 2016 and attempted to land on the Drone ship of course I still love you however this booster ran out of propellent when it was several meters off the deck suddenly dropping straight onto it breaking the engine section and producing a very sizable flame right after that of course it tobl over and blew up just like b162 did on this Landing what if something like this instead of happening meters off the deck just so happens to take place a little bit closer the impact speed would be lower there would still be damaged to the booster and legs a fire would break out and the booster would tip over sound familiar of course it might seem farfetched that suddenly a booster might run out of propellant but remember SpaceX is still pushing the limits of Falcon 9 reusability and it could be that they just came to the limits of what boosters can use in terms of propellent consumption there's also a bunch of other potential explanations to this as well like I don't know a clo filter in the oxygen iner that makes the engine underperform super heavy and just like that we can keep going on and on there's plenty of examples with this and other Rockets of how a rocket engine May suddenly underperform that doesn't need to be associated with wear and tear okay so let's assume that actually the landing speed we just talked about was okay and within the bounds it could then be that the landing leg just failed once again let's remember this booster was flying for a 23rd time and while we unfortunately don't know much about whether these Landing legs get changed out very often or not one could attribute this to where and tear the landing legs don't just allow the booster to settle on the landing Zone but they also take some of the force of the landing if these can't sustain the force they break and the booster toles over to absorb this impact the legs use shock absorbers first for low impact Landings and then Crush cors that then get used up if the landing is a bit more rough the tougher The Landing the more the legs get crushed and therefore the booster gets lower on the deck of the ship one can imagine that if the legs just completely fail to absorb the booster's landing speed even if that speed is within the bounds then the engine nozzle would hit the deck of the Drone ship if they crack this could make the booster own kerosene leak out from them and then produce the fire we see followed by the booster tipping over the third option on our list is that the Drone ship may have just been in rough Seas the booster uses a radar altimeter located at the base of the OCTA web in order to precisely know how far it is from the deck of the ship but if a rogue wave were to hit the ship just as the vehicle came in for landing then it could raise its deck such that the booster ends up touching down at a higher speed than usual breaking the engine section and legs and producing the fire and tip over we were wondering about this ourselves so we consulted our local boat expert Gavin to take a look at the buoy data and see if the sea state was rough or not according to data from a buy 45 Mi to the northeast of the landing Zone se's in that location had a significant wave height of 2.6 ft or about 80 cm that is not really that high and in the normal range for what Falcon 9 can handle and has handled in the past overall this is more in the calm sea territory for Falcon 9 and not a particularly rough sea state if we look further at the weather forecast from the 45th weather Squadron we can see that they had rated the additional risk criteria of recovery zone weather as low so this was not really an envelope pushing Mission so the theory of a high wave while not impossible seems rather unlikely at this moment one interesting thing to point out is that despite everything we just talked about the booster came down pretty much on a bullseye even our own Jack berer pointed this out when it touched down only to realize what was about to happen next Bingo right in the center oh no oh no oh no no no no no no no no we've looked at three potential causes for this based on the limited information we have but maybe we forgot to consider something else and frankly there's a lot of other things in play during Landing for example the radar altimative could have failed it happened already once in 2016 and it resulted in the booster using up all of the crush cores on its Landing legs by some sort of Miracle it survived the landing but it had a noticeable lean when it returned to the port that booster was then refurbished and flew again as the Falcon heavy side booster for the Falcon heavy demo flight and it is now on display in the Gateway exhibit at the KSC visitor complex now after saying all of this I'm sure you're probably already scroll into the comments section to point out all of the other potential theories we missed good we like that tell us if we've missed something and we'll give it a thought as I said at the start of the video though SpaceX has a lot more data than we do and we'll investigate this anomaly and hopefully tell us what happened at some point but the next question remains what are the implications for upcoming launches I mean we have the history making Polaris Dawn Mission coming up soon a bunch more starlinks and lots of other customer missions as well well in the short term it already had an impact on spacex's manifest as the Starling group 95 mission was scr before it could launch it was planned to launch just a couple of hours after this Mission from Vandenberg but SpaceX released a statement saying quote standing down from our second starlink launch of the night to give the team time to review booster Landing data from the previous launch a new Target launch date will be shared once available that makes sense if you do not know what went wrong you should probably not launch again and risk losing another booster something like this could in theory be applied to Polaris Dawn as well the mission right now is planned for Friday night and if SpaceX hasn't reached a conclusion by then it wouldn't be surprising to hear this delaying further in any case it's awaiting acceptable Dragon splash down weather anyway so that'll probably take a higher priority in the launch Readiness than this incident for now with Polaris Dawn being a crude Mission there is of course an additional layer of safety in place and SpaceX will want to make sure they understand what is going on before flying four astronauts into space but some of you might say but it's a landing it does not matter for the safety of the crew and yes imaginary YouTube comment this is in theory correct however if the failure is because of the Merin engine that engine is also used during Ascent when the crew is you know on top of the rocket SpaceX may want to take some time to confirm that this is something that happened only during this booster landing and no other booster has a similar issue if something is indeed wrong then it's best to find it now while polar st's booster is still on the pad in fact during post- production we've had comments from both SpaceX VP of Falcon launch Vehicles John Edwards and VP of launch Kiko donev Edwards ended with quote one thing we do know though is that this was purely a recovery issue and posed no threat to the primary Mission or Public Safety whil Donair followed with lessons learned from recovery failures will not only improve recovery reliability but also assent reliability if you're familiar with Starship you may know that sometimes the Federal Aviation Administration or the FAA requests operators to stand down from missions when a mishap occurs we can find on the agency's website how and what it considers a mishap there's a whole list of nine points however it is not clear whether this Landing failure really enters within this ruling or not and even if it were would it meet any of these conditions for a mishap it's not very easy to tell it is because of this uncertainty that we contacted the FAA right after this anomaly took place the agency responded back and said quote the FAA is aware an anomaly occurred during the SpaceX Starling group 8-6 mission that launched from Cape canaval space for station in Florida on August 28th the incident involved the failure of the Falcon 9 booster rocket while landing on a drone ship at Sea no public injuries or public property damage have been reported the FAA is requiring an investigation so this clears up any doubts SpaceX will now need to perform a mishap investigation about this incident and Report their findings to the FAA as we've seen in the past SpaceX could return to flight if the FAA considers that the public safety was not endangered at any moment by issuing a public safety to termination we've seen this before with Starship flights and most recently with the launch failure of the starlink group 93 Mission SpaceX will need to request that safety determination and prove to the FAA that the public was never in any danger once the FAA agrees with it then SpaceX will be able to resume launches we don't know how long this would take but last time it was just 2 weeks so perhaps there won't be a huge impact going forward now one way to look at how SpaceX may act in the future based on this is by looking at what the company did previously the last time a landing failed was during the staric V 1.0-mm b159 was flying for a sixth time and was trying to attempt a landing on of course I still love you according to the explanation SpaceX provided back then this booster had a hole in the protective cover that they called the engine boot during Ascent the exhaust gas normally recirculates up into the engine section and these boots protect the fiddly bits of the engine from getting damaged on the way up and and on the way down during re-entry but due to that small hole the engine was damaged and shut down seconds before Mo since the booster was not going at the right speed and altitude at moo it missed the Drone ship altogether when that happened SpaceX delayed by a week or so a staring commission that it had planned to perform that same month moving it into early March remember this was when Falcon launches happened every week or two rather than every 3 or 4 days during an earlier booster Landing failure with b148 the booster also failed its Landing due to an engine failure during ascent and this also triggered an internal investigation at SpaceX and some delays on other missions as well so based on previous history SpaceX is just doing the same thing as it did before and there are no surprises here we'll just have to wait and see when they're comfortable enough to fly again but hopefully it's sooner rather than later some of you may also now be thinking wait a minute didn't another Falcon 9 fail a launch just a month and a half ago is Falcon 9 hitting a reliability limit well yes and no may have hit the reliability limit that it has now as Elon Musk spacex's CEO explained on social media quote now we will figure out what went wrong to drive the landing failure rate far above 1 in a th000 then 1 in 10,000 1 in a million Etc that is it may have hit its current reliability limit but thanks to this failure and figuring out what went wrong SpaceX will be able to learn a lot about what to improve on Falcon in order to bring that reliability even higher it's worth pointing out that this Landing failure broke a streak of 267 consecutive successful Landings this is more than the amount of consecutive successful parachute Landings for space captures for example and it is higher than the consecutive number of launches of any rocket except Falcon 9 of course so in the ground scheme of things it doesn't look to be such a huge deal Falcon reliability both on launch and Landing is indisputable also this was an old booster and it could just be that some wear and tear was behind this anomaly and they need to improve the longevity of some Hardware perhaps it's not related to reusability either maybe it was because of spacex's increased launch Cadence or maybe none of the above at the end of the day it's hard to tell so what are your thoughts do you think it had to do with any of this or was this just a one-off event let us know what do you think in the comments we'll be back with this week in space flight on Friday so make sure to tune in for any updates I've been Ryan Kon for NSF thanks for watching and goodbye