When looking for “great moments” in engineering history, it's tempting to lean toward efforts that went according to plan. However, true greatness arises in the face of adversity, and we often learn far more from our mistakes than we do from our victories. In the case of Apollo 13, the lesson (among others) learned was that “Enh, I'm sure it'll be fine” is not a solid design philosophy.
For those unfamiliar with the event, Apollo 13 was the ill-fated 1970 lunar mission in which a lack of oversight when the shuttle's oxygen tanks were upgraded led to a disastrous explosion that forced the crew to abort the mission and stranded them 200,000 miles from Earth.
With dwindling oxygen supplies and two-thirds of their power supply destroyed in the blast, the trio of James Lovell Jr., Fred Haise, Jr., and John Swigert, Jr., as well as their ground crew back on Earth, had to think fast if the crew were to have any hope of returning to Earth.
The next 90 hours saw some of the most impressive improvisational engineering in the 20th century. For instance, in order to bring their boys back home safely, NASA’s Mission Control developed procedures for 'waking up' Apollo's command module quickly—it had been shut down by the crew for the majority of the return journey in order to conserve whatever meager power was left. The command module was never designed to power up this quickly, and so these procedures had to be developed from scratch.
To put this in perspective, writing up and testing these procedures in a simulator and going through rigorous iterative testing to ensure their effectiveness and reliability normally had an estimated start-to-finish time of three months.
Mission Control did it in three days.
Meanwhile, the Apollo crew was no less impressively jury-rigging replacements for cutting-edge equipment out of what was essentially junk it had laying around. Picture building a functional Lamborghini out of paper clips, and you have a picture of the absurd tasks that the three not only attempted, but managed to accomplish successfully.
I highly recommend reading the entire mission report on the NASA website, but a CliffsNotes of some of the things the crew did includes:
- Correcting a faulty seal on the command module hatch using the couch located in said command module
- Rewiring the fuel cells in the lunar module to charge those in the command module while it was 'asleep'—while extending the life expectancy of the lunar module from 45 hours to 90 hours—while running on one-third of their power supply
- With the help of Mission Control, devising a way to transplant CO2 disposing lithium hydroxide canisters from the command module to the lunar module using cardboard, plastic bags, and tape. Seriously.
Even beyond that, the Apollo 13 event is a culturally and historically significant one for multiple reasons. First, it reiterated the stakes involved anytime an engineer embarks on a project. One uncrossed t or undotted i can put lives at risk. Apollo 13 put faces to those lives and reminded all those involved of the importance of maintaining rigor even in the smallest detail.
Writing about the months following the event in his 1970 book Manned Spacecraft, Kenneth Gatland described how the models of O2 tanks involved were tested to recreate the circumstances of the explosion, revised to keep it from happening again, as well as how the crew used several emergency procedures for “alleviating pressure in a cryogenic oxygen tank” if it did occur again. Failing that, all wiring in the power system bay was upgraded with a sheathing of stainless steel to mitigate damage in the event of another explosion.
Even during the crisis, Houston Ground Control quickly internalized the lesson: their lightning-quick turnaround and transmission of procedures to Apollo 13's crew is even more impressive given that all the same precautions and safety measures normally adhered to were maintained; they were just hyperconcentrated into a nerve-wracking, sleep-deprived 72-hour period.
Finally, the rescue put into focus for the average person what makes engineering such a fascinating pursuit, and those involved in it worthy of respect. Many times, we get to see the fruits of engineering labor after the fact. But rarely does the problem-solving process—the endless repetitions and failures, and the hours of analyzing a situation from a hundred different angles to find a solution—get acknowledged.
Because the country was watching as the minds both on Earth and in space raced to cobble together a plan through ramshackle resources, for one of only a few times in modern history, the wider public got to see the gears turning that result in the mechanical marvels we take advantage of every day.
Apollo 13 may not be logged in the NASA record books as a successful mission, but it arguably won more hearts and minds through the tenacious ingenuity shown during adversity than it would have in completion.
For more engineering history, find out Who was the First Engineer.