The Space Shuttle’s Luckiest Escape

This is the space shuttle lifting off on what was about to become one of its most dangerous Journeys into space. Almost immediately fuel started leaking out of its right engine and just 5 seconds later an electrical supply failed knocking its engine control computers offline. Unaware of what was really going on beneath them the space shuttle crew spent the next 8 minutes just moments away from a catastrophic failure when suddenly they ran out of liquid oxygen. The shuttle had experienced two major problems that should have ended the mission but miraculously, they happened in such a way that actually ended up saving the crew  from complete disaster. We modeled the entire thing to show you the tiny objects that led to these huge problems and how sheer luck and miraculous circumstances ended up saving the space shuttle. In order to understand why this flight was so dangerous in the first place we need to look inside the shuttle's payload bay. It was carrying the Chandra Observatory Telescope which was the largest and heaviest thing shuttle ever launched. This combination put the mission  over the shuttle's weight limit. It had to shave off several tons before the flight and so the crew was limited to five people a lighter external tank was used and all three main engines were swapped out for lighter ones. One of these was engine 2019 which had already flown on 18 missions making it one of the most used space shuttle engines. Over time cracks had started to show in a couple of its liquid oxygen posts These are the thin pipes that carry liquid oxygen into the combustion chamber. If one of these failed mid-flight it would rip the engine apart and destroy the entire vehicle.  Instead of replacing these NASA simply deactivated them by placing a small metal pin at the top which  stopped the liquid oxygen from flowing through. This was common practice for NASA and it saved the  engine from going through a lengthy refurbishment but as space shuttle Columbia ignited its engines, one of these metal pins worked its way loose and shot itself into the combustion chamber at over 30 m/ second. In the blink of an eye it bounced off the chamber walls and punctured a hole in the  delicate engine nozzle. This part of the engine is made up of over 1,000 thin tubes which circulate the ultra-cold liquid hydrogen to stop the nozzle from melting. From here the hydrogen makes its way  into the combustion chamber where it ignites and produces thrust. When the pin collided with the  nozzle it ripped a hole in three of the pipes and liquid hydrogen began pouring out of the engine. If just two more of these pipes had been damaged the nozzle would have melted causing a chain reaction  that would have completely destroyed the vehicle. The space shuttle was just barely hanging on but all of this went completely unnoticed since none of the sensors could detect the leak. What the sensors did detect was a lower chamber pressure since less hydrogen was making its way into the combustion chamber. In order to fix this the onboard computers automatically started pumping more liquid oxygen into the engine which brought the pressure back up to the correct amount. This meant that the shuttle was now burning through its liquid oxygen too quickly and if it continued like this it would run out way before reaching orbit. But while all this was going on a completely  unrelated electrical problem had occurred in the vehicle which put the shuttle offline and it was  no longer vulnerable to hackers ... Just kidding. That isn't what happened. But did you know that Incogni - today's sponsor can protect you from hackers and spam emails? We all get pointless spam emails and  phone calls from things we never signed up for. This is because Data Brokers sell our personal  information to marketing agencies who then make it their life goal to fill our inboxes with spam. The problem is even worse since the databases that your info is stored on can easily be leaked or stolen by criminals. Incogni reaches out to these  marketing agencies on your behalf and gets them to delete any data they have about you. All you need to do is sign up, sit back and watch Incogni do their work. Since signing up with Incogni my info is no longer in the hands of any of these companies and my inbox is much cleaner. To protect your personal information and get rid of spam in your life visit incogni.com/primalspace and use the code PRIMALSPACE to get 60% off. Space Shuttle Columbia had just left the launch pad and was already on the verge of a complete disaster. Its right engine was burning through too much liquid oxygen and if it ran out the shuttle might not have made it into orbit or even worse, the engines could have ripped themselves apart. Amazingly a completely separate  problem was about to save the day. Inside the payload bay were a series of electrical wires that carried power to instruments all over the vehicle. One of these wires ran alongside a small screw  that had been overtightened and had a very sharp edge. Over the course of many flights, this wire had rubbed against the screw and its insulation had been slowly worn away. 5 seconds into the flight the exposed wire arced onto the screw causing a short circuit and setting a number of instruments offline. This immediately set off all kinds of warnings inside the cockpit one of which was a fuel cell warning. The fuel cells aboard shuttle used hydrogen and oxygen to produce all of the electricity for the vehicle. If one of these went wrong the results would be catastrophic.  Luckily this was just a faulty reading and there was nothing wrong with the fuel cells. The real problem was lurking down below. Two computers in charge of controlling the shuttle's engines had been knocked offline thanks to the electricity shortage. Each engine had a main computer and a backup computer which would take over if something went wrong. The right engine, which was leaking fuel  had just lost its backup computer and the center engine lost its main computer. This caused a unique problem that actually turned into a solution. You see, under normal circumstances both computers run simultaneously. The data from both computers is compared and averaged out and this is what is used to control the engines. This means that if a sensor on one of the computers is reading abnormally high or low it won't have such a big effect on the engine. As it turned out, the pressure sensor on the backup computer was reading incorrectly and it was sending back an abnormally high pressure reading. Since the main computer wasn't there to cancel this out it tricked the engine into thinking  the pressure was too high. Because of this the engine started pumping less liquid oxygen into the engine to reduce the pressure. This now meant that although the right engine was guzzling through too much oxygen the center engine was using less than normal and so the problems canceled each other out. If the center engine didn't have a faulty sensor  or if the electrical supply hadn't failed the whole shuttle would have run out of liquid oxygen much sooner and it wouldn't have reached orbit. Had this actually happened, the crew would have had to make an aborted landing back on Earth still carrying the enormous telescope on their backs. By sheer coincidence, two completely separate problems  occurred that perfectly canceled each other out allowing shuttle to reach orbit just 5 m/ second off its desired speed. In the end, the shuttle was able to make up for this by using its OMS engines and the Chandra Telescope was successfully deployed. Since its main engines weren't needed for the rest of  the mission, the shuttle and its crew safely made it back to Earth without any issues. Now time for the Primal Space giveaway. The winner of the previous giveaway is Eric. Congrats! In the next video, we'll be giving away this custom Primal Space design Shuttle poster available in our store. All you need to do is sign up at the link below like the video, and leave a comment saying what you think about the Space Shuttle. Thank you very much for watching and I'll see you in the next video.

Channel: Primal Space

Views: 320,997

Keywords: NASA Space Shuttle, NASA Space Exploration, NASA Space Disaster, Shuttle Mission, Columbia, Chandra Observatory Telescope, Chandra Telescope, Columbia Space Shuttle, Space Shuttle Columbia, NASA Space Shuttle Columbia, Space Shuttle Columbia Disaster, STS-93, STS-93 Launch, STS-93 Landing, Chandra X-Ray Observatory, Launch of STS-93, NASA Primal Space, Space Shuttle Columbia Engine Start Failure, Space Shuttle Columbia Fuel Leak, Space Shuttle Columbia STS-93, STS93

Id: qiJMdfj9NmI

Length: 8min 10sec (490 seconds)

Published: Fri May 24 2024