April 13
Apollo 13 Oxygen Tank Explodes in Space
A routine stir of cryogenic oxygen tanks aboard Apollo 13 triggered an explosion that crippled the spacecraft's power and life-support systems, forcing the crew into an improvised return from deep space.
Summary
Launched on April 11 as NASA's third planned lunar landing mission, Apollo 13 carried astronauts Jim Lovell, Jack Swigert, and Fred Haise toward the Moon. Two days into the flight, on April 13, a damaged wire in an oxygen tank short-circuited during a routine stir, igniting insulation and causing a massive explosion that ruptured the service module. The blast disabled fuel cells, venting oxygen and crippling power and life support systems nearly 200,000 miles from Earth. Swigert famously reported, “Houston, we’ve had a problem here.” The crew aborted the landing, used the lunar module as a lifeboat, and executed a risky circumlunar trajectory to return safely on April 17.
Context
By 1970 the Apollo program had already achieved two crewed lunar landings, building on the orbital flights of earlier missions and the groundbreaking Apollo 8 circumlunar voyage. NASA aimed to expand scientific exploration of the Moon's surface with targeted landings in geologically significant regions such as the Fra Mauro highlands. Apollo 13 was planned as the third landing attempt, carrying a crew experienced in Gemini and prior Apollo flights under the command of veteran astronaut Jim Lovell.
What Happened
The spacecraft lifted off from Kennedy Space Center on April 11, 1970, with Lovell as commander, Jack Swigert serving as command module pilot after a late crew change, and Fred Haise as lunar module pilot. The early phase of the flight proceeded without major incident, including a scheduled television broadcast from the spacecraft. On April 13, roughly fifty-five hours after launch and more than 200,000 miles from Earth, mission control directed the crew to activate fans that stirred the cryogenic oxygen tanks to obtain accurate quantity readings.
Aftermath
The explosion immediately disabled two of the three fuel cells that supplied electricity, light, and water, while oxygen vented rapidly from the damaged service module. With only minutes of command-module power remaining, the crew shut down Odyssey and relocated to the lunar module Aquarius, which became their lifeboat for the remainder of the journey. Controllers in Houston quickly developed new procedures for power management, water conservation, and carbon-dioxide removal using improvised adapters fashioned from materials already aboard the spacecraft.
Legacy
The investigation that followed identified manufacturing damage and testing oversights in the oxygen tank as root causes, prompting NASA to adopt more rigorous quality controls and component redesigns for the remaining Apollo flights. The mission's safe return reinforced the importance of redundant systems, extensive simulator training, and real-time problem-solving between crew and ground teams, lessons that shaped subsequent human spaceflight programs and public understanding of spaceflight risks.
Why It Matters
The incident demonstrated the resilience of NASA engineering and crew training, leading to major safety reforms in spacecraft design and mission protocols that influenced subsequent Apollo flights and later programs. It highlighted the risks of space exploration while reinforcing public support for the space program through the dramatic successful rescue.
Related Questions
What specifically caused the oxygen tank explosion?
A damaged wire inside the tank short-circuited during the stir procedure, igniting insulation and leading to the rupture.
How did the crew generate enough power and remove carbon dioxide in the lunar module?
They conserved electricity by powering down nonessential systems, charged command-module batteries from lunar-module supplies, and built an improvised adapter using plastic bags, cardboard, and tape to connect square command-module canisters to the lunar module's round environmental system.
Why is Apollo 13 often called a 'successful failure'?
The crew returned safely despite the loss of the primary spacecraft, and the incident produced lasting improvements in spacecraft design and mission procedures.
What role did Mission Control play in the rescue?
Controllers developed entirely new procedures in real time, calculated precise engine burns, and guided the crew through power-up sequences and resource management that had never been tested in flight.
Related Portfolio Site
Daily Earth View: Apollo 13 Oxygen Tank Explodes in Space connects to space, astronomy, satellites, or Earth observation history.
Explore More
Related Events
Sources
- Apollo 13 Mission Details, NASA. Accessed 2026-07-09.