The following is an Encore presentation of Everything Everywhere Daily. On April 11, 1970, Apollo 13 was launched from Cape Canaveral, Florida, as the third mission to land on the Moon. However, it never achieved its mission objective. Despite having failed in its goal, it still managed to return to Earth, and in its own way achieved a type of success it never could have planned for.
Learn more about Apollo 13, the most successful failure in the history of spaceflight, on this episode of Everything Everywhere Daily. Despite only two previous moon landings, by April 1970, the public had become blasé towards landing on the moon. Apollo 11 received all the attention as it was the first moon landing.
Apollo 12 broke its television camera so there were no live videos for the public to watch. By the time Apollo 13 came around, the television networks didn't even bother covering the launch because they felt there wasn't enough interest. Apollo 13 was to be the most ambitious mission yet. With two successful moon landings under their belt, NASA was to send Apollo 13 to a site just north of the Fra Mauro Crater.
It was intended to be one of the 4-H missions, which was to be a two-day stay on the moon with two moonwalking sessions outside the lunar module, also known as the LEM. The commander of the mission was Jim Lovell, who had previously flown around the moon on Apollo 8 and was also a veteran of Gemini 7 and 12. He was to become the first person to fly into space four times.
Landing on the moon of Lovell was the lunar module pilot Fred Hayes. Hayes was a civilian test pilot, and it was to be his first flight into space. The command module pilot, the guy who would orbit the moon while the other two were on the surface, was Jack Swigert, and it was also to be Swigert's first trip into space.
Swigert was actually a late replacement for the original command module pilot Ken Mattingly, who was scrubbed from the flight after exposure to Rubella. The flight launched with only one minor incident with an engine on April 11, 1970. For 56 hours, the mission went according to plan. They did a short television program on board, and after their TV broadcast, they stowed their cameras and went about doing some routine maintenance.
One small glitch that appeared was that the pressure sensor inside the oxygen tank on the service module was malfunctioning. In response to the glitch, Mission Control requested the crew turn on a fan inside the tank to mix the oxygen. Normally, this was done once a day, but because of the malfunction, they requested they do it manually. At 9.08 p.m. ET, Swigert, as requested, flipped the switch for the fan for a few seconds.
About a minute and a half after Swigert turned on the fan, the crew heard what they described as, quote, a pretty loud bang, followed by a fluctuation of the electrical supply and a firing of the altitude control thrusters. Half a minute later, Swigert famously sent an understated message back to Mission Control saying, quote, Houston, we've had a problem. The crew had no idea what had happened.
The problem, as it was later discovered, was that the particular oxygen tank used on Apollo 13 had been installed on Apollo 10, but later removed. While it was being switched out, it was dropped slightly. It didn't appear to cause any damage, but it turned out it did. Prior to launch, during a test run, they needed to remove the liquid oxygen in the tank, but it wouldn't empty.
So they turned on a heater inside the tank to turn the liquid oxygen into a gas so it could vent. A thermostat inside the tank was to prevent temperatures from ever getting above 80 degrees Fahrenheit or 25 degrees Celsius. The problem was, back in 1965, the Apollo program had changed the standard of their electronics from 28 volts to 65 volts. All of the electronics had to be changed to accept both 28 and 65 volts.
The heater in the tank was never upgraded. When they turned on the heater during the test run, the 65 volts overwhelmed the thermostat, which was designed for 28 volts, and caused it to weld shut. Unbeknownst to everyone, Apollo 13 was flying with a bomb. When Schweiger turned on the fan, the welded-shut thermostat caused temperatures to rise inside the oxygen tank, eventually rupturing due to excessive pressure.
While the astronauts didn't know the cause of what happened, they certainly knew what was happening to their ship. Two of the fuel cells on board, which used oxygen and hydrogen to produce electricity, were dead. Oxygen levels were plummeting. Gases were clearly being vented into space. The onboard computer had reset, and their high-gain antenna wasn't functioning. It was very quickly made clear that they weren't going to land on the moon.
Mission protocol required all the fuel cells to be functioning for a moon landing attempt. Mission Control scrambled to come up with a solution to save the astronauts. The key problem was actually electricity. They had to save what they had to make it back to Earth. To this end, Mission Control ordered the three men into the lunar module. The LEM was designed to support two men for about 45 hours. Now it would have to support three men for 90 hours. It was going to have to be their lifeboat.
If the explosion had taken place after a successful moon landing on their way back to Earth, the entire crew would have died because they wouldn't have had the LM to take shelter in. They cut water rations to one-fifth their normal amount. Temperatures inside the LEM were just above freezing. All electrical systems beyond the absolute minimum necessary were turned off.
Moreover, in a total design oversight, the carbon dioxide scrubbers in the command module were square, whereas in the lunar module, they were circular. Even if they could survive, they had to return to Earth. That would require firing rockets to escape the gravity of the moon. However, to do that, they needed to use the rocket on the lunar lander, which was never designed for orbital maneuvers.
Moreover, the navigational computer was offline, so they had to do everything by hand, something which had never been done around the moon before. Because they never went into orbit around the moon, but rather just swung around it, they actually set the record for the humans who traveled the furthest from Earth, an inadvertent record that still stands today. While all of this was happening up in space,
everyone suddenly started to care about Apollo 13. The fate of the astronauts became the biggest story in the world. Church services were held for the astronauts, and television networks were providing nonstop coverage. The odds were looking quite grim for the astronauts, and it was shaping up to be the first American disaster in space. In the cold of the spacecraft, Fred Hayes actually caught the flu as well as developed a urinary tract infection.
They actually couldn't expel their urine as they normally would because expelling that small mass would actually alter their trajectory ever so slightly. They had to keep it on board in sealed bags. On April 17th, they were approaching the Earth.
Despite everything that they had been through, and having managed to survive to this point, they were approaching the most dangerous part of the mission. To re-enter the Earth's atmosphere, they would have to hit it at exactly the right angle. Too steep, and they would burn up. too shallow and they would skip off the atmosphere and go into space. They had one and only one shot at getting it right. Prior to re-entry, they had to fire their rockets to make another correction.
This, as with the firings around the moon, had to be done with the LEM and by manual navigation. Just one hour before entry, the crew re-entered the command module and jettisoned their life raft, the LEM. The big unknown throughout this whole ordeal was if the explosion had damaged the heat shields on the command module. If the heat shields were damaged, then the men were doomed.
It wasn't possible to do a spacewalk to check the damage, and even if they could, there was nothing they could do to fix it. Just before re-entry, they jettisoned the service module, which was the section of the ship connected to the command module with all the fuel. With this, they could finally see the damage to the spacecraft. One of the panels on the service module was totally blown away and they could see the rest of the extensive damage to the ship.
Another problem they faced was that water had condensed all over the walls of the spacecraft. The astronauts feared that if there was water on the walls, then there was probably water behind the walls too, which could result in short circuits of the electrical equipment.
As they enter the Earth's atmosphere, the re-entry heat and ionized gases around the capsule prevented radio contact with the ground for about four minutes. Whereas none of the television networks bothered to cover the launch, the entire world covered their re-entry. As they entered radio silence, everyone in the world held their breath for four minutes. If the heat shields had failed, there would be nothing to splash down. In the event that they should land far off their planned landing site,
Nations around the world offered their ships to rescue the capsule if necessary, including the Soviet Union. Eventually, live TV cameras aboard the USS Iwo Jima picked up the sight of the capsule descending with its three open parachutes. Despite all the difficulty in their jerry-rig navigation, their landing was almost perfectly on the mark. Apollo 13 brought about renewed interest in the Apollo program.
More people paid attention to Apollo 13 than any other space mission before other than Apollo 11. President Nixon tried to capitalize on the attention given to Apollo 13 by giving the Presidential Medal of Freedom to the Apollo 13 crew and also to the mission operations team in Houston. NASA did an investigation into what caused the disaster, which quickly led them to discover the problem with the oxygen tank thermostat. Changes to the electronics were implemented immediately for Apollo 14,
which was able to successfully land at Fra Mauro, where Apollo 13 was supposed to land. None of the Apollo 13 astronauts ever went into space again. Jack Schweigert passed away in 1982, just weeks after having been elected to Congress and one week before his term was to begin. Fred Hayes and Jim Lovell are still around at 89 and 94 years old, respectively, at the time of recording.
Despite its failure, Apollo 13 has been widely called NASA's finest hour. Against all odds, Mission Control managed to improvise and save all three astronauts in what was a seemingly impossible situation. It wasn't the last disaster for NASA, nor was it even close to the worst. But the lessons learned from Apollo 13 led to improved safety for spacecraft, which are still in place today. And that is why Apollo 13 can be called NASA's most successful failure.
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