Starship's Hottest Upgrade: Hot Staging!

Starship is getting ready to launch again and we might even see a launch just days from now so we thought it is the right timing to catch you up on the biggest change from flight one to flight two in the infrastructure hot staging how does it work why does SpaceX want to do it and how was it implemented on Starship let's get started sponsored by [Music] hcan [Applause] in this video we will go from generic to specific so if you want to see Starship directly bear with me for a moment here we will get there let's start with the concept of hot staging hot staging means firing your next stage engine while the previous one is still attached for example look at this Falcon 9 footage for the recent stalling Mission Falcon 9 does not do hot staging first the nine Merin engines on the Boost to shut down before the stage then separates and later after a short coasting phase the second stage Merlin vacuum engine ignites so why is this time considered wasted all of these seconds are not used to fight gravity which Faline or any other rocket could fight at this moment would they not stop firing their engines SpaceX even tried to counteract this effect on some Starling missions with the reduction in Coast time of the second stage before the ignition of the MC they try to cut it down by multiple seconds every second you're not firing you're losing efficiency and here hot staging enters the ring hot staging is not a Brand New Concept the Russian N1 and other Russian Rockets already performed hot staging or tried it so it is something that has worked on Rockets before the difference here is that a it is used on the most gigantic rocket of all time and B on a rocket that still needs to reuse the first stage and land or caught it after all that is the concept of Starship full reusability so it's kind of counterintuitive to toast your first stage before trying to land it but more on how SpaceX tries to protect that stage later hot staging reduces the time that is not used to fight gravity you are not waiting in a step-by-step maneuver but going quickly from the first to the second stage Elon Musk has claimed in exceed that hot staging could increase the payload capacity of Starship by up to 10% that seems like a minor deal initially but if we look at the current payload ballpark for Starship according to the SpaceX website that would increase the capacity of Starship between 10 to 15 Tons that's almost a reusable Falcon line you gain by that single Improvement alone you can also replace any Pusher or rotation stage separation mechanism all you have to do is release the first stage and if the frust to weight of the upper stage is is higher than the one on the first stage it will just fly away from the booster without any pushes or something else needed that's simplification on that front as well when I'm not wearing a watch it just feels wrong and that's especially true here in Star base or when chasing Rockets or just in everyday life keeping track of and managing your time is essential so that you can spend that time consciously this video sponsor holzkern is a small Austrian company that is the leading brand for wooden watches and natural jewelry Hol Kern strives for diversity and uniqueness and this shows with their over 1,000 designs all of which have ties to Nature as someone who loves our planet and loves nature I appreciate their use of natural materials and commitment to sustainability wood is a beautiful thing and the melding of wood with metal that holzkern achieves is absolutely delightful which makes sense after all hr's goal is to provide an individual connection to Nature even even though we live in a modern high-tech Society holar uses production techniques packaging and delivery routes that are as sustainable as possible and they support reforestation projects together with different partners such as the Jane Goodall Institute Holz Kern's watches and jewelry are naturally unique and uniquely natural no two pieces are exactly the same owing to their use of wood and other natural materials that way you can find something that suits exactly what you like help out our Channel and get a personal piece of nature for yourself or a loved one by clicking the link in the description for a limited time only holzkern has a Black Friday deal where if you get one watch you get a second watch 50% off thanks again to holzkern for sponsoring this video another thing that hot staging would solve is the problem of settling the second stage propellant at the ignition of Starship let me explain there during an engine startup you want to ensure that the stuff you are pumping into your engine is the required liquid not gas bubbles that can also form in your tank as the propellant starts to boil some Rockets like the San 5 solve this using ulage Motors other upper stages like santow used the RCs to push the liquids to the bottom of the tank before ignition with this hot staging the acceleration would keep the propellant at the bottom of the tank imagine pushing your gas pedal in the car all the way through it pushes you back into the seat this is another advantage of hot staging as it solved the problem of ensuring the propellent is in the right place at the right time so how does all of this look well you all have probably seen the hot staging ring by now in its countless stacks and D Stacks the hot staging ring placed on the booster is a single barrel of 2 m or 6 ft this has been heavily modified and instead of a solid surface of the other Rings this one has multiple opening allowing the exhaust to escape inside the interstage you can see how SpaceX try to maximize the open space in the ring as even in the areas where other hardare whereare prevented a fully sized cut they still try to squeeze in a small opening there are reinforcements inside the ring to ensure it is equipped with the maximum stability it can get while not compromising the openings on the inside of the ring there's also a dome this Dome is attached to the ring and covers the whole base of it while it goes smaller at the top at the top of the ring you can see hole points that will be attached to the ship during flight at the bottom it will be connected ected to the top of booster 9 as it will stay attached to the booster after stage separation the main challenge of this concept is a fight between two direct interests that conflict with each other on the one hand openings in the ring will compromise the area stability on the other hand bigger openings allow the thrust and exhaust to escape during hot staging if the Raptors would fire into a closed interstage you could have a bursting interstage that would break on the weakest point so you want more openings but not too much just the right amount it will get especially tricky as the booster gets lighter and lighter why do you ask the lighter the booster gets the higher the acceleration on the entire stack at the end of stage one flight the booster will be almost empty pushing against the Starship second stage with all that acceleration and since the hot staging ring is between them all that force will go through it so it needs to be durable this was why SpaceX built a Pathfinder hot staging ring which was the same design but without a dome in the middle this design was placed on the can crusher test stand at the M's test site the device can inflict vertical stress on the hot staging ring and with that SpaceX verified the Prototype structural Integrity it is safe to assume that with SpaceX putting a similar design on the top of booster 9 these tests succeeded and achieved the expected flight load you might ask why was the Dome not included in this test well good question unknown voice because it does not impact the overall load capacity of the Ring it is built there for a different reason thrust deflecting and that will become more apparent once we go through the maneuver of hot staging during hot staging the booster will shut down all engines besides the center ones these three will fire during the hot staging then the ship will spin up its engine to build up thrust the important thing is that it needs more individual acceleration than the booster that is pushing below it this should be achievable with a good margin since the booster engines are also pushing against the weight of the booster which the ship engines are not during this moment the thrust of the Raptors is directed at the area of the forward Dome from the booster this would not be a problem for an expandable booster and SpaceX would not care if this Hardware would be damaged but that is not the case with Starship right they want to reuse these boosters down the line so the hot staging cannot damage them introducing the Dome inside the hot staging ring this Dome will take the Raptor's fire and deflect it to the outside while the arva cannot gimbal we will probably even see the sea Lev Raptors gimble to the outside to further help spread the thrust to the outside to protect the forward Dome of super heavy this could even be needed as the space between the Dome and the engines would be very limited otherwise we then arrive at the last step of the hot staging separation the booster separates from ship and the ship Glides away while the booster performs the Boost back burn this maneuver does not impact the rest of both ship and booster flights once the stages have separated everything else should be business as usual which is a funny saying for something that has never been achieved yet of course of course to make this happen other modifications were also needed to make this concept work but these modifications are surprisingly minor the main change was the change of the ship QD umbilical position with the booster now 2 m taller the ship would rest on a 2 m higher position hence the position of the quick disconnect interface Also Rises by that height so SpaceX needed to modify the ship QD to raise it by 2 m this change was already done month ago and since then we have seen multiple movements test on the system to verify the change was successful another advantage of the design we have seen now over and over again is that the ring is quickly removable while some panicked about that it is a pretty fast process for Rocket terms they can remove the ring to access the sensible areas below it on top of booster 9 on the forward Dome motors for all four grid fins are hosted as well as batteries and electronics so having quick access to this area is crucial but apparently it has not been an issue for SpaceX as they removed the ring and put it back on multiple times now that's it that's the quick explain about hot staging what do you think will this work will the booster be able to survive and return for future flights or will SpaceX even change the concept and develop something that will surprise us again let us know in the comments below see you next time

Channel: NASASpaceflight

Views: 100,160

Keywords: SpaceX, Starship, Hot Staging, Space Travel, Rocket Science, Space Innovation, Stage Separation, Falcon 9, XYZ Mission, Payload Capacity, Propellant Management, Structural Stability, Reusable Rockets, Space Exploration, Booster Design, Space Technology, Rocket Mechanics, Aerospace Engineering, Interstage Design, Thrust Management, Starship Launch, spacex boca chica, starship spacex, spacex launch, starship launch update, starship launch 2

Id: 4O3_iBOmXi4

Length: 11min 29sec (689 seconds)

Published: Wed Nov 15 2023