Imagine a space shuttle blasting off on what would become one of its most dangerous missions ever. Right after takeoff, things started to go wrong. Fuel began leaking from the right engine, and just five seconds later, an electrical problem knocked out the engine control computers. The crew, unaware of the chaos below, spent the next eight minutes on the brink of disaster until they unexpectedly ran out of liquid oxygen.
Two major issues occurred during this mission, either of which could have ended in catastrophe. However, by sheer luck, these problems happened in a way that ended up saving the crew. Let’s dive into what happened and how luck played a crucial role in this mission’s success.
To understand why this flight was so risky, we need to look at what the shuttle was carrying. It had the Chandra Observatory Telescope onboard, the largest and heaviest payload it had ever launched. This made the shuttle exceed its weight limit. To compensate, the crew was reduced to five people, a lighter external tank was used, and all three main engines were replaced with lighter ones. One of these engines, known as engine 2019, had already been used in 18 missions, making it one of the most experienced engines.
Over time, small cracks had developed in some of the engine’s liquid oxygen posts, which are thin pipes that carry oxygen into the combustion chamber. Instead of replacing these, NASA inserted small metal pins to stop the oxygen flow, a common practice to avoid lengthy repairs. But during this mission, one of these pins came loose and shot into the combustion chamber at high speed.
In an instant, the pin bounced around and punctured a hole in the engine nozzle, which is made of over 1,000 thin tubes that circulate cold liquid hydrogen to keep it from melting. The pin damaged three of these tubes, causing hydrogen to leak out. If just two more tubes had been damaged, the nozzle would have melted, leading to a disaster.
Despite this, the sensors didn’t detect the leak. They only noticed lower pressure in the chamber, so the computers automatically pumped more liquid oxygen to balance it out. This caused the shuttle to burn through its oxygen too quickly, risking running out before reaching orbit.
At the same time, an unrelated electrical issue occurred. A wire had been rubbing against a sharp screw, wearing away its insulation. Five seconds into the flight, the exposed wire caused a short circuit, knocking some instruments offline and triggering warnings in the cockpit. Fortunately, the fuel cell warning was a false alarm.
The real issue was that two computers controlling the engines went offline. Each engine had a main and a backup computer. The right engine lost its backup, and the center engine lost its main computer. This unusual situation turned out to be a blessing in disguise.
Normally, both computers work together to control the engines, averaging data to ensure accuracy. However, the backup computer’s pressure sensor was faulty, sending back a high reading. Without the main computer to correct it, the engine thought the pressure was too high and reduced the oxygen flow.
This meant that while the right engine was using too much oxygen, the center engine was using less, balancing the situation. If the center engine hadn’t had a faulty sensor or if the electrical failure hadn’t occurred, the shuttle would have run out of oxygen much sooner, forcing an emergency landing with the heavy telescope onboard.
By pure coincidence, two separate problems canceled each other out, allowing the shuttle to reach orbit just slightly off its target speed. The shuttle used its OMS engines to adjust, and the Chandra Telescope was successfully deployed. With the main engines no longer needed, the shuttle and crew safely returned to Earth.
This mission is a remarkable example of how unexpected problems can sometimes lead to a lucky escape. It reminds us of the complexities and challenges of space travel and the importance of preparation and a bit of luck.
Imagine you are part of the space shuttle crew. Create a timeline of the mission, highlighting key events such as the fuel leak, electrical problems, and the lucky break. Use drawings or digital tools to illustrate each event. This will help you understand the sequence of events and how they interrelated.
Create a safety poster that outlines the potential risks of space travel and the importance of backup systems. Include information on how the shuttle’s design helped prevent disaster during this mission. This activity will reinforce the concept of risk management in space exploration.
In groups, role-play a scenario where you are the mission control team responding to the shuttle’s issues. Discuss how you would prioritize problems and communicate with the crew. This will help you understand the decision-making process in high-pressure situations.
Research how space shuttle engines work, focusing on the role of liquid oxygen and hydrogen. Present your findings to the class, explaining how the engine’s design contributed to the mission’s lucky escape. This will deepen your understanding of the technical aspects of the shuttle.
Write a short story from the perspective of a crew member on this mission. Describe your emotions and thoughts as the events unfold. This creative exercise will help you empathize with the astronauts and appreciate the human element of space exploration.
Here’s a sanitized version of the provided YouTube transcript:
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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 situation 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.
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 payload the shuttle had ever launched. This combination put the mission over the shuttle’s weight limit. The crew had to shave off several tons before the flight, so they were 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, which are the thin pipes that carry liquid oxygen into the combustion chamber. If one of these failed mid-flight, it could have catastrophic consequences. 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 saved the engine from going through a lengthy refurbishment. However, 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/s.
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 that circulate ultra-cold liquid hydrogen to prevent the nozzle from melting. 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 could 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 lower chamber pressure since less hydrogen was making its way into the combustion chamber. To compensate, 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 before reaching orbit.
Meanwhile, a completely unrelated electrical problem occurred in the vehicle, which caused some instruments to go offline. One of these wires ran alongside a small screw that had been overtightened and had a sharp edge. Over the course of many flights, this wire had rubbed against the screw, and its insulation had been worn away. Five seconds into the flight, the exposed wire arced onto the screw, causing a short circuit and setting a number of instruments offline. This triggered various warnings inside the cockpit, including a fuel cell warning. The fuel cells aboard the shuttle used hydrogen and oxygen to produce electricity for the vehicle. Fortunately, this was just a faulty reading, and there was nothing wrong with the fuel cells.
The real problem was that two computers in charge of controlling the shuttle’s engines had been knocked offline due to the electrical 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, lost its backup computer, and the center engine lost its main computer. This created a unique situation that turned into a solution.
Under normal circumstances, both computers run simultaneously, comparing and averaging data 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 a significant effect on the engine. As it turned out, the pressure sensor on the backup computer was reading incorrectly and 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. Consequently, the engine started pumping less liquid oxygen into the engine to reduce the pressure.
This meant that although the right engine was consuming too much oxygen, the center engine was using less than normal, effectively canceling out the problems. If the center engine hadn’t had a faulty sensor or if the electrical supply hadn’t failed, the shuttle would have run out of liquid oxygen much sooner and wouldn’t have reached orbit. Had this occurred, the crew would have had to make an aborted landing back on Earth while still carrying the enormous telescope.
By sheer coincidence, two completely separate problems occurred that perfectly canceled each other out, allowing the shuttle to reach orbit just 5 m/s 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 returned to Earth without any issues.
Now, time for the giveaway. The winner of the previous giveaway is Eric. Congratulations! In the next video, we’ll be giving away a custom design shuttle poster available in our store. To enter, sign up at the link below, like the video, and leave a comment sharing your thoughts about the Space Shuttle. Thank you for watching, and I’ll see you in the next video.
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This version removes any promotional content and maintains a focus on the narrative of the space shuttle’s mission.
Shuttle – A vehicle designed for repeated travel between two places, often used for space missions. – The space shuttle carried astronauts to the International Space Station.
Engine – A machine designed to convert energy into useful mechanical motion. – The rocket’s engine was powerful enough to propel it into orbit.
Oxygen – A chemical element that is essential for combustion and respiration. – Astronauts need a supply of oxygen to breathe while in space.
Mission – A specific task or operation assigned to a person or group, often in the context of space exploration. – The mission to Mars aims to gather data about the planet’s surface.
Telescope – An optical instrument designed to make distant objects appear closer and more detailed. – The telescope allowed scientists to observe distant galaxies.
Hydrogen – The lightest and most abundant chemical element, often used as a fuel in rockets. – Hydrogen fuel is used in rockets because it provides a lot of energy when burned.
Circuit – A closed path through which an electric current flows or may flow. – The circuit board in the robot was responsible for controlling its movements.
Pressure – The force exerted on a surface per unit area. – The pressure inside the submarine must be carefully controlled to keep it safe underwater.
Computers – Electronic devices that process data and perform calculations at high speed. – Computers are used to simulate the conditions of space travel before a mission is launched.
Disaster – A sudden event that causes great damage or loss, often used in the context of failed missions or experiments. – The engineers worked hard to prevent a disaster during the rocket launch.
