NASA, Mars 2020, Nuclear power, Nuclear thermal rocket, Nuclear propulsion X Starship Number 9 Makes Perfect* Flight (*except for the landing which was a huge fireball)
This was starship sn9. It had been ready to go after sn8, crashed and burned, but had been held up by a combination of spacex’s, lean development process, engine problems and the faa approvals. But we’ll talk about that later. By now, you’ve probably heard the landing didn’t go as planned. This is what happened: the vehicle was in the horizontal uh descent orientation. It tried to light two engines to perform the landing burn, but only one lit it lost control and ended up crashing at about 200 kilometers per hour 120 miles per hour. If you look at photos of the pad after this there’s a lot less debris left on the pad. But if you look at that white cloud there, that is liquid oxygen in the header tank and one of the cool ways we know this is well the slow motion footage, but one of the tank watchers lab padre has a thermal camera, and this is normally great Because you can see the tank filling, but when you see this landing, you see the hot area for the explosion and the black area on the right as the liquid oxygen spills everywhere and reduces the temperature. Also note the mushroom cloud actually rising up this wasn’t a nuclear explosion, but this was a pretty big boom and, as it turns out, a big boom was one of the reasons why this launch took so long to get approved by the faa. According to the faa spacex for the sn8 flight, they were supposed to request a waiver to allow them to fly this without actually doing the math doing the investigation about the effects of the blast uh.
They flew without doing that, and the faa said no. You guys have to do like we have to do a whole investigation into your entire safety culture, because we think it’s bad, that you would consider launching without actually getting proper approval, and you know it’s worth breaking out google maps here just to get a lay of The land – and so this is the area you can see: spacex launch facility down there in boca chica state park, it’s on an area that’s it’s, basically a like an island connected by a road and you’ll. Actually, if you look at the map in detail, you’ll find there’s a lot of people that drive out there in cars, so they have to clear that out whenever they are having a launch and the sheriffs will set up a roadblock on this roadway. Now the nearest sort of urban area is up north that’s, the south padre island there that’s on on the other side of the shipping channel. There are actually a lot of cameras from the tank watchers up on that island, but there are actually closer residents. There’S a village right next to the spacex construction facility and tracking station, and this was bokuchika village and because it’s so close to where they were testing stuff. Spacex has been trying to buy these people out of their homes so that they can essentially take control of the area and not have to evacuate people every time. They’Re performing a test with the potential for explosions, but there are a few people who have resisted their financial incentives and they play host to a whole bunch of cameras in their backyards, which, let us see these kind of views and while we’re admiring this look.
There’S. Four different stainless steel, pressurized things there i mean we’ve got sn8 on the right, purging its engines, ready to go there’s the test tank sn7 sn10 standing vertical and in the middle of the tanks is hoppy there, which is now where they mount all of the cameras And radars – and things like this, so i believe this camera is attached to hoppy and the great thing about this angle is, you can see the undersides of sn10, which is closest to us, an sn9 which is further away, and you can see the black patches where They are testing the thermal protection tiles now they’re for these small hops they’re not going fast enough that they need thermal protection, but what they’re just doing is they’re testing. The tiles will remain fixed to the surface, using the the pins that they’re, using and by the way spoiler. I don’t think there’s many tiles left attached to sn9 so anyway, fast forward to the actual flight. There was a bit of a pause in the clock at 13 seconds, but they continued. We got the signature three vent squirt and the all three engines lit and sn9 started, it’s a sent towards the target of 10 kilometers that’s. What they had been authorized to do for this flight, so obviously for a test flight taking off from the pad. They have to use a lower propellant load than you would normally get in a fully loaded, starship uh.
This will have to have the header tanks because need to perform transition maneuver, but there’s a great shot showing all three of the engines lit up, and they also included some on board cameras, including this one off the bay, see that as raptor number 49 also note. Some flickering flames and over on the top right of that camera there’s some flapping panels there. Those are thermal protection materials that are protecting things like pressure vessels inside the skirt and those are important later because i think that’s what we see falling off from this angle. Also notice that if you look straight up, it does look like the flame there’s a bit of smoke in the air i’m, not sure if that’s significant, we’re, not sure, if it’s, because it’s, perhaps running a little more fuel rich for throttle reasons. Frankly, we don’t know very much but yeah at this point. It is a fairly long ascent where they deactivate the engines one by one until they reach apogee, apogee being when sn9 gets as high as it’s gon na get, and that on this flight happened around 420. So this was about 10 kilometers up and by this point it’s only flying on a single raptor engine enough to just keep it going at the velocity. It was when all the others shut down, so it cuts that off and then proceeds to go into the belly flop. Maneuver in this case they overcooked it just a bit.
Now we weren’t sure about the camera angles on this, but it definitely looked like the nose goes down, because if you look at other camera angles, it seems to confirm this, but then they use aerodynamics. They increase the drag on the nose fins by folding them further out and the rear fins get folded in and they bring it down to the horizontal belly flop maneuver. So this, of course, maximizes the drag and sets the terminal velocity initially it’s about. You know: 300. 400 kilometers per hour, but as they descend into the thicker parts of the atmosphere it drops down to about 250 kilometers per hour. I love these shots showing the fins working which, if finn’s actuating, to control the descent, but the camera froze typical. But look the good news for this flight is the transition from the vertical to the horizontal and controlling the belly flop were really good. It was consistent, which means those were the things i had the biggest concern about. Oddly enough, i haven’t had huge concerns about the reliability of the raptors, although given what happened next i’m, perhaps beginning to reassess that situation, so they’re supposed to light up two raptors, and only one of the raptors lights, the second one, it just coughs, it splutters and We end up going into fireball mode, okay, so let’s look at this in quarter speed. One thing to notice, first of all, is the nose by now is covered in frost because, of course that’s where the oxygen header tank is, you can see the two vents coming out to the sides.
Those are from the engine shell system, i believe so as it gets close to the ground it’s falling at about 70 to 80 meters per second and it starts to go to light up the engine. So the important thing to note is that the first engine comes on and starts generating, really good, mark diamond so there’s the ignition and you get a nice rocket like flame. The second one goes up, and it doesn’t do that at all so note that this second, the first engine keeps producing these good mac diamonds, which is an indication of good thrust. All the way through it gets it flares a bit here and there, but it then recovers so that engine is good all the way down. There’S no failure going on there, but the other engine fails to light which says to me that there may be a problem with that specific rapture on the relight. It wasn’t a vehicle issue or it’s, most likely, not a vehicle issue. Um it’s, certainly not the low pressure, any specific uh, your fuel or oxidizer system, but it’s, something that affects that engine and not the other one. Maybe there’s a void or a bubble in the tank that went and caused the engine to stutter and fail we’re, not sure we’ll have to get more data now there’s other things to see from this angle. First of all, there’s a couple of items that are seen to get blown out during this and as far as we can tell, they are much lighter, so there’s, the first one shooting off to the left and it’s getting caught up in the air.
We actually see that it falls slower than the rest of the vehicle. The second one is falling off to the right and off to the top. So we think these are just shielding that is inside the skirt to protect things like composite overwrapped pressure vessels things that wouldn’t react too well to too much heat. In fact, if you watch this pass enough, you’ll actually start to see the second thing bouncing around inside the skirt before it’s blown out but yeah. If the other thing to watch is the engine that’s failing slightly at this point, you can actually see there’s flames at the base of that engine or the head because we’re looking at it from below, so the power head is very likely falling apart. So this is very much looking like an engine failing and coming apart, and the question is: was it a flaw in the engine? Did it just break because it’d been run for too long or was there something in the system feeding it because you know yeah? If you have a void in a pipe and it is being pumped hard enough into the engine, when that hits your pump or hits the impellers, it can damage your turbo pump, destroy it and result in an rud. That looks very much like this and we should point out. This is very distinct from what happened on sn8. In that case, the starship had a fuel supply problem pressure was too low, the oxygen get fed into the engines, and we got this bright.
Green flame of engine rich exhaust as the engine destroyed itself due to a failure in starship. This could be a failure of the engine most likely, but it could be something that only affects that engine in starship fuel supply. So we’ll have to wait to find out what really happened here i suspect now, while spacex is no doubt going to be doing their own internal analysis, the community are already out there sleuthing in the way that a bunch of texas tank watchers only can so. We have rgv aerial photography, who pretty much arranged a flyover as soon as the airspace restrictions were lifted, and this is a very different scene to sn8, where we had very large chunks visible on the pad. This is the stuff is spread all over the place. The vehicle hit at a much higher speed and if you look at some of the other angles, you’ll see the the debris is flying off in every direction. We actually know how fast it hit because, of course, flight club io has been out there. Analyzing everybody’s pictures and trying to figure out the altitude, the speed the velocity doing the math so that everybody else can figure out what what was really going on and according to this yeah it’s uh free fall velocity right at the point where it was firing. The engine was probably about 80 meters per second, when it lit its engine and you know, started to decelerate.
It could have hit the ground whoa say about 69 meters per second, of course, by this point with sn8, we knew exactly what went on because elon told everyone on twitter, but right now, he’s decided he’s, taking a twitter break, so we’re left to look at pictures. Watch explosions, and maybe when the sun rises over boca chica, we might get a few more clues from the debris left. Laying around spacex will have to have their own investigation. They’Ll have to satisfy the faa that they understand what went wrong and how they’re going to remedy it, and only then are they going to get to fly sn10, which is sitting out there and that’s, assuming the sn10 wasn’t damaged by being in close proximity to sn9. Perhaps this is spacex engineer’s way of incentivizing sn10 to do as it’s told, otherwise its fate might be similar either way. I wish it the best of luck. I’M.