Apollo 13 - The Successful Failure
Imagine you are 200,000 miles away from home and you are about to run out of oxygen. What would you do?
On April 11, 1970 Nasa launched John Swigert, Fred Haise, and Captain James (Jim) Lovell on Apollo 13 with the goal of landing on the moon. Approximately 56 hours into the mission, 200,000 miles from earth, the No. 2 oxygen tank aboard the spacecraft exploded.
The story of Apollo 13 offers many lessons about how to come together as a team to solve challenging tasks. We cannot all become astronauts, but we can use some of the same skills and techniques the Apollo 13 crew used to ensure their safe return. Space exploration requires large teams of scientists, engineers, technicians, pilots, and so many other staff in order to run a successful mission. You can watch the full mission at apolloinrealtime.org. This website showcases a comprehensive set of radio communications, video footage, news conferences, and mission data for the entire 152 hour mission. It includes detailed photos and diagrams showing the layout of the command module and landing module.
Once a decision is made to launch a crew into space, a detailed planning process ensues. Protocols and checklists are developed and tested to ensure the crew can go on their mission safely. Teams plan, build, and test every piece of equipment. During a mission, everyone must be quick-thinking and strategic in the way they attempt to solve the issue at hand. This article discusses the value of communication, problem solving, checklists, working with limited resources, benefits of simulations and drills, and leadership.
Part 1
“Houston, we’ve had a problem here.” Jim Lovell
The No. 2 oxygen tank that was installed on the Apollo 13 service module was a refurbished tank from the Apollo 10 module. During one of the testing procedures, the No. 2 oxygen tank was not emptying as designed. While the history on this tank is detailed, the final decision was to use the electrical heater within the tank to “burn off” the remaining oxygen. It was unknown at the time, but this heating process ended up damaging the No. 2 oxygen tank that would lead to an explosion while in space.
Days before, the launch backup pilot Charles Duke unknowingly exposed the Apollo crew to Rubella. Since the original command module pilot did not have immunity to Rubella, he was replaced by John Swigert days before the launch. Backup crews are always trained and in place ready to step in at times like these. It changed the crew dynamic, but consistent training make these transitions as smooth as possible. Soon after liftoff, the S -II engine on Apollo 13 shut down two minutes early. This caused the remaining engines to burn longer in order to get the spacecraft into orbit. This unexpected event put the crew on edge.
Approximately 56 hours into the mission, 200,000 miles from earth, the No. 2 oxygen tank aboard the spacecraft exploded. The No. 1 oxygen tank also began to fail as a direct result of the explosion. Warning lights indicated that one oxygen tank was empty and the second was depleting rapidly. Two of the three fuel cells were no longer functioning; the fuel cells supply the module with its power. While all of this was happening, the crew also observed that there was a gas leaking from the spacecraft.
Amid the chaos of radio communications, the decision was made to relocate the crew from the command module (CM) to the landing module (LM), using the landing module as a “life boat.” After isolating the problem, and determining the extent of damage, the next step was to figure out how to get the crew safely back to Earth.
Part 2
Failure is not an option.
Once the crew was safely relocated to the landing module, mission control and the crew members needed to assess what resources they had available to them, and had to develop entirely new procedures to bring the crew home. The main problems included: navigation, rationing consumables like water, extending the battery supplies, removing excess carbon dioxide from the air, surviving the cold, and developing a new landing procedure. It normally takes months to plan, write, and test new procedures, but mission control no had a matter of days to develop a plan.
Missions are carefully choreographed. Nicely formatted checklists and procedures ensure that information is quickly accessible to everyone involved in the mission. Captain Jim Lovell’s cuff checklist currently resides in the Alder Planetarium in Chicago Illinois. This cuff checklist is attached to the astronaut’s wrist for quick viewing, with all the key elements they need to remember. The point of the checklists are to provide a clear list of instructions on how to perform the mission; they also attempt to predict possible complications and provide quick solutions. This photo of two pages of the checklist strapped to Lovell’s wrist reminds the astronaut to ‘duck’ to avoid getting entangled in the antenna lines while on the moon surface. This part of the checklist was never used because the crew never made it to the moon surface. Mission control began to develop new procedures immediately in order to develop a safe way to return the crew back to earth. NASA provides a full set of the Apollo 13 mission rules which can be downloaded here. Within the mission rules there is a list of all potential failures or malfunctions, with a predetermined action to take depending on the stage of the mission. When seconds count, a checklist becomes the most valuable item to have.
The landing module was designed to disconnect from the command module and go down to the surface of the moon. Since the crew was relocated to the landing module, new procedures had to be developed to extend the life of the module that was originally built for 45 hours of use, to 90 hours. Oxygen was not an immediate concern due to additional reserves that were onboard, but other consumables like power, water, and carbon dioxide removal became paramount. Failure was not an option.
Part 3
“We have no more water in the potable tank” -Jim Lovell
Resource management enabled the astronauts to return safely to Earth.
Procedures were developed to reduce power consumption in the module and limit the use of power to about 20% of normal levels, which was just enough to keep critical systems functioning. When the electrical systems were turned off to reduce power, this reduced the amount of heat generated in the spacecraft. The temperature dropped and as the mission progressed condensation began to form on the inside of the spacecraft. Although the astronauts were cold, the bigger concern was the amount of condensation that was building up on the electronics. There were concerns that short circuits could cause a fire when restarting the electrical systems.
Procedures that normally normally took three months were written in three days to develop the proper method of restarting electrical systems, and due to critical safeguards installed, there were no short circuits. These safeguards were developed after the catastrophic fire that occurred on board the Apollo 1 shuttle in 1967.
The landing module was designed for two men for two days, and now as a “life boat” it was required to sustain three men for four days. Carbon dioxide (CO2) is removed by using canisters of lithium hydroxide to filter the contaminant. The canisters from the command module were square, and the canisters for the landing module fit in round openings only. As CO2 alarms began ringing in the landing module for excess CO2, mission control raced to develop a method to connect the square canisters to the circular openings using materials that the crew had on board. Mission control communicated the procedure to the crew, and they were able to use tape, cardboard, plastic bags, and other materials in order to secure the canisters and reduce the build up of CO2 in the landing module. With limited supplies on board, the crew could not afford to cut something incorrectly so mission control had to be precise with their instructions.
Navigation using the landing module was going to be a challenge. In order to navigate back home the crew was required to complete two burns using the landers engines. During the burns, the orientation of the spacecraft was crucial to ensure a correct trajectory. An Alignment Optical Telescope (AOT) was normally used to ensure the correct alignment of the spacecraft. This method was no longer viable because the earlier explosion created so much debris that the stars could not be viewed clearly enough for the system to function correctly. A method was developed by mission control to use the sun as a navigational star, and was sighted manually by Captain Lovel. Precision was crucial because firing the engines with an incorrect orientation could have sent the spacecraft on an incorrect flight path. The first burn was short, but the second burn lasted for nearly five minutes.
As the crew was getting closer and closer to earth, they eventually ran out of water approximately 25 hours before landing. The astronauts rationed the water to a minimal daily intake of 6 ounces per day. Their meals were adjusted to mostly wet foods. On April 17, 1970 the crew landed safely in the pacific ocean near Samoa, where the U.S. navy greeted them with celebration.
Nasa Mission Control was headed by lead flight director Gene Kranz. His team, and many others, were tasked with constant calculation, decision making, and task management. No one could have predicted or trained for the number of issues the crew and mission control faced on the Apollo 13 mission in 1970. The Apollo 13 mission was designated a successful failure because the crew was returned safely even though the odds were stacked against them. The success can be attributed to the amount of training and planning that goes into mission preparation. Procedures, chain of command, teamwork and clear communication were crucial to bring the crew back home safely.
The story of Apollo 13 shows that with the right amount of determination, we can achieve the improbable.
If at first you don’t succeed, fail successfully, then try again.
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