“Houston, we’ve had a problem” (see notes 1 below this post) is the now-famous phrase radioed from Apollo 13 to Mission Control upon the catastrophic explosion that dramatically changed the mission. On the 50th Anniversary of the Apollo 13 mission, NASA recognizes the triumph of the mission control team and the astronauts and looks at the lessons learned. The American space agency commemorates the most “successful failure” in the history of space exploration with the video titled “Apollo 13: Houston, We’ve Had a Problem”.

Today’s (April 13) story of what happened this day in Science, Technology, Astronomy, and Space Exploration history.

“Houston, we’ve had a problem” is the now-famous phrase radioed from Apollo 13 to Mission Control upon the catastrophic explosion that dramatically changed the mission. NASA says “on the 50th Anniversary of the Apollo 13 mission, we recognize the triumph of the mission control team and the astronauts, and look at the lessons learned. The Apollo 13 mission has become known as “a successful failure” that saw the safe return of its crew Commander James (Jim) Lovell Jr., Command Module Pilot John Swigert Jr., and Lunar Module Pilot Fred Haise Jr.” “Thanks to Stephen Slater and Ben Feist/Apollo in Real-Time (apolloinrealtime.org/13) for providing additional footage and audio. Thanks to Andy Saunders for providing additional enhanced images.”

Apollo 13

Apollo 13 was launched from the Kennedy Space Center on April 11, 1970. It was the seventh crewed mission in the United States’ Apollo space program and the third meant to land on the Moon. The mission was commanded by Jim Lovell (born March 25, 1928), with Jack Swigert (August 30, 1931 – December 27, 1982) as command module (CM) pilot and Fred Haise (born November 14, 1933) as Lunar Module (LM) pilot.

Two days into the mission, on April 13, an oxygen tank in the service module (SM) exploded, and the lunar landing of the Apollo 13 mission was aborted. The crew looped around the Moon instead and returned safely to Earth on April 17.

Apollo 13 Mission commander Jim Lovell’s phrase, “Houston, we have a problem” (see notes 1) has become popular, being used to account, informally, for the emergence of an unforeseen problem.

Houston, We’ve Had a Problem

James A. Lovell, Jr., Commander, Fred W. Haise, Jr., Lunar Module (LM) Pilot, John L. Swigeft, Jr., Command Module (CM) Pilot.

Swigert: Hey, we’ve got a problem here.

Thus, calmly, Command Module Pilot Jack Swigert gave the first intimation of serious trouble for Apollo 13 – 200,000 miles (320,000 km) from Earth.

Capsule Communicator (CAPCOM): This is Houston; say again, please.

Lovell: Houston, we’ve had a problem (see notes 1 below that post).

Swigert: We’ve had a main B bus undervolt.

By “undervolt”, Swigert meant a drop in power in one of the Command/Service Module’s
two main electrical circuits. His report to the ground began the most gripping episode in
humanity’s venture into space. One newspaper reporter called it the most public emergency
and the most dramatic rescue in the history of exploration.

Transcript of the video

A mission plagued by bad luck from the very beginning

Jim Lovell recalls:

“It (the Apollo 13 mission) was plagued by bad omens and bad luck from the very beginning. “

Just days prior to launch, the original command module pilot, Ken Mattingly, was exposed to measles. A replacement was made from the backup crew, and Jack Swigert had replaced Ken Mattingly.

The flight began as planned. Unknown at the time, the spacecraft was damaged prior to launch.

Lovell recalls:

“Years before the flight, when the spacecraft was being built, a damaged liquid-oxygen tank was installed in the spacecraft. The tank had been dropped on the factory floor, a little piece of plumbing had prevented the normal procedure for removing oxygen after a routine test prior to the flight. And then on the day, before the flight, we filled up the tank again with liquid oxygen, and it was a bomb waiting to go off.”

At the end of the second day of the mission, the crew made a TV broadcast from space.

A large bang – now we have a problem

Fred Haise recalls:

“Actually it was the end of the workday. We were fixin’ to go to bed after we did a few things to clean up – and the next morning, going to lunar orbit, and get ready to land.”

“And then, that was a large bang.”


“When the explosion first occurred, -uh, we didn’t know what had happened.”


“And that just rang through the metallic structure.”


“I was at the Lunar Module (LM), and I went down to the Command Module (CM). We started looking at the instrument panels – one of the quantity gauges, one of the tanks was zero. That was the tank that had blown. I then looked out the window, and saw escaping at a high rate of speed, gaseous oxygen.”

“Because the explosion occurred on the first damaged tank, but also ruptured the second tank. Just blew the entire side of the spacecraft off.”


“My immediate feeling was just a sick feeling in the pit of my stomach, a disappointment. I knew we had lost the landing.”


“And from then on, it was not a third landing on the moon (After Apollo 11 and Apollo 12), but a survival of how to get home.”

Apollo 13 Flight Director Glynn Lunney recalls:

“At the time, it’s scary as the devil, and we were handling something that we knew was – out of control. Every team that came on was dealing with a major set of problems to deal with.”

“They just jumped to the task and they knew what they had to do.”

Lunar Module (LM) as a lifeboat

Voice of Gene Kranz, Apollo 13 Lead flight director:

“OK, now lets everybody keep cool, we got the LM (Lunar Module) still attached, the LM spacecraft’s good, so if we need, uh, to get back home, we got an LM to do a good portion of it with.”

The Lunar Module (LM), built to land on the Moon, became the crew’s lifeboat.


“One of the biggest things we had to do in the dying moments of the electrical system in the Command Module (CM) was to transfer the guidance system. And transfer the angle numbers from the Command Module to the Lunar Module.”

“And we only had about fifteen minutes to do that.”

As they flew toward the Moon, the next step was to calculate a return home.


“About 20 minutes after the explosion, it was obvious that we weren’t coming to a landing on the Moon. We were gonna go around it. Glenn had already been down in the trench with the trajectory guys, and came up with five trajectory return to Earth options.”


“So, we would’ve missed the Earth – had we done nothing. So, the first thing was to get us in the right direction to go around the Moon. And that was the first maneuver we made. We used the landing engine, the engine we normally would’ve used to land on the Moon.”

Carbon dioxide problem

With every exhale of the crew, carbon dioxide, which was absorbed by canisters of lithium hydroxide pellets, became a concern. The LM’s stock of canisters meant to accommodate two astronauts for 45 hours on the Moon, was not enough to support three astronauts for the return journey to Earth. The CM had enough canisters, but they were the wrong shape and size to work in the LM’s equipment.

Engineers on the ground devised a way to bridge the gap, using plastic, covers ripped from procedures manuals, duct tape, and other items. NASA engineers referred to the improvised device as “the mailbox”. The procedure for building the device was read to the crew by CAPCOM Joe Kerwin over the course of an hour, and it was built by Swigert and Haise; carbon dioxide levels began dropping immediately.

"Houston, we've had a problem": Apollo 13 Command Module pilot Jack Swigert
“Houston, we’ve had a problem”: Apollo 13 Command Module pilot Jack Swigert with the rig improvised to adapt the CM’s lithium hydroxide canisters for use in the LM.


“Everybody seemed to be moving in the right direction without being directed. Everybody had a sense of what had to be done.”

“The training guys brought the simulators up over there, and the crew was over in the simulators, tracking virtually everything they were doing. – every configuration change that was proposed to be done was already being worked over in the simulators there.”

“So you start getting answers from all these various directions.”

Baby, it’s cold inside

To conserve electricity, the crew shut down most systems. This caused a loss of heat. Sleep was almost impossible because of the cold. Water condensed inside of the spacecraft.

Apollo 13 Hasselblad image (Jim Lovell)
“Houston, we’ve had a problem”: Jim Lovell tries to rest in the frigid spacecraft. By Jack Swigert / NASA, Public Domain, Link


“The command module was very wet. There was water everywhere. In the Lunar Module, there are no inner walls, so you can see water on all the connectors, a glob of water, plumbing, every turn, a glob of water…”

“And from the Command Module, we actually get towels out to wipe off the instrument panel to see the instruments.”

An engine burn around the Moon, and a course correction pointed the crew toward a safe return to Earth. The Service Module was jettisoned. Then, the crew finally saw the damage from the explosion.

Apollo 13 damaged service module
“Houston, we’ve had a problem”: Apollo 13 damaged service module

Back to Earth

The crew prepared for the re-entry and jettisoned the Lunar Module.


“So, it was a question of getting this entire world geared and oriented to one single job: get the crew home.”


“Teamwork was necessary. Good leadership, initiative, to think outside of the box when things go wrong – how do we repair them? Those are the three things that were absolutely necessary.”


“I was most proud of being in this team that knew what they had to do, and there was no doubt about it. The team completely faced up to what had to be done. In this case, it was a survival challenge that we were faced with.”

Apollo 13 crew after splashdown
Apollo 13 crew after splashdown. Apollo 13’s shallow reentry path lengthened this to six minutes, longer than had been expected; controllers feared that the CM’s heat shield had failed. On April 17, 1970, Apollo 13 Command Module “Odyssey” regained radio contact and splashed down safely in the South Pacific Ocean, 21°38′24″S 165°21′42″W, southeast of American Samoa and 6.5 km (3.5 nautical miles) from the recovery ship, USS Iwo Jima.
Apollo 13 control room - cigars
It’s cigar time!


1. “Houston, We’ve Had a Problem” vs “Houston, we have a problem”

Jim Lovell actually said, “Houston, We’ve Had a Problem”. The erroneous wording “Houston, we have a problem” was popularized by the 1995 film Apollo 13, a dramatization of the Apollo 13 mission, in which actor Tom Hanks, portraying Jim Lovell, uses that wording, which became one of the film’s clichéd taglines. Since then, the phrase has become popular, being used to account, informally, for the emergence of an unforeseen problem.


M. Özgür Nevres
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