The Apollo 13 crew members were:
1. James A. Lovell (Commander)
2. John L. Swigert (Command Module Pilot)
3. Fred W. Haise (Lunar Module Pilot)
The back up crew were:
1. John W. Young (Backup Commander)
2. John L. Swigert (Backup Command Module Pilot)
3. Charles M. Duke, Jr (Backup Lunar Module Pilot)
Note: The original Command Module pilot for this mission
was Thomas 'Ken' Mattingly, but due to exposure to measles he was replaced by
his backup, Command Module pilot John L. Swigert two days before launch.
The name of the Command Module was Odyssey (CM-109) and the name
of the Lunar Module was Aquarius (LM-7).
Command Module Mass: 28,945 kg
Lunar Module Mass: 15,235 kg
Lunar Landing Site: Assigned to Fra Mauro region of Moon
Landing on Moon: Landing aborted after oxygen tank explosion. Spent upper
stage successfully impacted on the Moon.
9:08 p.m. EST, April
Oxygen Tank Explosion:
10:08 PM EST, April 13, 1970: 321,860 km from Earth
Splash-Down: April 17,1970 1:07 p.m. EST Pacific Ocean
Mission Duration: 5 days, 22 hours, 54 minutes
Crew Changes: Measles
On 6 April 1970, Dr. Charles A. Berry (NASA's Medical Director) reported
that the main crew had been exposed to measles. Backup lunar module pilot
Charles Duke had a case of german measles (rubella) and Jeffrey Lovell, the
commander's son, was down with the red measles (rubeola).
Two days before launch, the flight surgeons grounded Ken Mattingly (command
module pilot) as he had no natural immunity to the disease and Lovell and Haise
had had the measles as children. He was replaced by his backup, Command Module
pilot John L. Swigert. This may have been a blessing in disguise for Mattingly
as he never developed the measles and was re-assigned as command module pilot of
Duke's flight, Apollo 16. He also flew several Space Shuttle flights, while none
of the Apollo 13 astronauts flew in space again.
Apollo 13 was launched on Saturday, 11 April , 1970 at 13:13 CST on a
Saturn V rocket from
Pad 39-A from Kennedy Space Center, Florida, USA as part of a manned mission in
the Apollo Program. The control centre for the mission was in Houston, Texas.
Moon Rocket Problems
At five and a half minutes after lift-off, Swigert, Haise and Lovell felt a
little vibration. Then the centre engine of the S-II second stage shut down two
minutes early. This caused the remaining four engines to burn 34 seconds longer
than planned and the S-IVB third stage had to burn nine seconds longer to put
Apollo 13 in orbit.
Engineers later discovered that this was due to dangerous pogo oscillations
which might have torn the second stage apart. Smaller pogo oscillations had been
seen on previous Apollo missions, but on Apollo 13 they had been amplified by an
unexpected interaction with the cavitation in the turbo-pumps.
Lunar Flight Plan Modification
Ground tests before launch, indicated the possibility of a poorly insulated
supercritical helium tank in the Lunar Module descent stage so the flight plan
was modified to enter the Lunar Module three hours early in order to obtain an onboard
readout of helium tank pressure.
Moon Landing Location
The Apollo 13 mission was scheduled to explore the Fra Mauro formation (or
Fra Mauro highlands), named after the 80 kilometre diameter Fra Mauro crater,
located within it. It is a widespread, hilly geological area covering large
portions of the lunar surface around Mare Imbrium and is thought to be composed
of ejecta from the impact which formed the mare.
Apollo 13 Disaster
At 46 hours, 43 minutes mission elapsed time, Joe Kerwin, the CAPCOM on duty
said, "The spacecraft is in real good shape as far as we are concerned. We're
bored to tears down here".
Nine hours, 12 minutes later, Apollo 13 was more than 54 hours into its lunar
mission (two days after launch), at a distance of 321,860 kilometres (199,990
miles) from Earth and more than halfway to the Moon when on 13 April 1970 an
explosion ruptured an oxygen tank in the Service Module and damaged an entire
panel, including all the tanks and systems inside it. The explosion was caused
by a fault in the number two oxygen tank, one of two tanks contained in the
Service Module. The Odyssey Command Module's normal supply of oxygen, power and
water was lost.
Mission Control had requested that the crew stir the oxygen tanks, a task
required to prevent the oxygen ‘slush’ from stratifying. The Teflon-insulated
wires that provided electricity to the stirrer motor were damaged, causing a
large fire when electricity was passed through them. The fire heated the
surrounding oxygen, increasing the pressure inside the tank above its nominal
1,000 PSI (7 MPa) limit and causing the tank to explode. The cause of the
explosion was unknown at the time. The crew and Houston thought that a meteoroid
had struck the Service Module or even the Lunar Module.
Oxygen tank number two had a faulty tank heater thermostat which never
opened, causing the tank heater to be on constantly during the flight. The tank
heated up to such an extreme temperature that the insulation was burned from the
internal tank wiring. When the astronaut turned on the tank fan to stir its
contents, an electrical spark arced on the bare wires, caught fire, and the
oxygen rapidly burned. The resultant pressure caused the tank to explode.
Hey Houston, We've had a Problem Here
At 46 hours 43 minutes Joe Kerwin, the CapCom on duty, said, "The spacecraft
is in real good shape as far as we are concerned. We're bored to tears down
At 55 hours 46 minutes, as the crew finished a 49-minute TV broadcast showing
how comfortably they lived and worked in weightlessness, Lovell pronounced the
benediction: "This is the crew of Apollo 13 wishing everybody there a nice
evening and we're just about ready to close out our inspection of Aquarius (the
LM) and get back for a pleasant evening in Odyssey (the CM). Good night".
Nine minutes later, oxygen tank No. 2 blew up, causing No. 1 tank also to fail.
The crew came to the slow conclusion that the normal supply of electricity,
light, and water was lost and they were were about 200,000 miles from Earth.
They did not even have power to gimbal the engine so we could begin an immediate
return to Earth.
Jack Swigert saw a warning light that accompanied the bang and was the
first astronaut to call down to
mission control. He said, "Houston, we've had a problem here".
Lovell came on and said the similar phrase: "Houston, we've had a problem' and
informed ground that it was a main B bus undervolt. The time was 21.08 hours on
Thirteen minutes after the explosion, Lovell happened to look out of the
left-hand window, and saw the final evidence pointing toward potential
catastrophe. "We are venting something out into the- into space," Lovell
reported to Houston. Jack Lousma, the CapCom replied, "Roger, we copy you
venting." I said, "It's a gas of some sort".
It was oxygen gas escaping at a high
rate from the second and last oxygen tank.
Lunar Module Lifeboat
command module was not powered down until approximately 2 hours after the
explosion. During those hours, the command module was running on its re-entry
batteries and one barely functioning fuel cell. When oxygen tank number one
finished its slow leak into space, the last surviving fuel cell was shut down
and the crew powered down the command module to save the remaining battery power
for later entering Earth’s atmosphere. With severe constraints on power, cabin
heat and potable water, the crew endured great hardship and survived by using
the Lunar Module still attached to the Command Service Module, as a 'lifeboat'.
The Lunar Module was designed to sustain two people for 50 hours, but by
carefully conserving both air and power, three astronauts survived in this
improvised lifeboat for 95 hours (about 4 days). The lithium hydroxide canisters
available for the Lunar Module's carbon dioxide scrubbers would not last for all four
days. The CM had an adequate supply of replacement canisters, but they were the
wrong shape to fit the Lunar Module's receptacle. An adapter then had to be fabricated
from materials in the spacecraft.
The Lunar Module temperature was only a few degrees above freezing and water
was rationed to just six ounces per person per day. Due to debris from the
explosion, the navigation system was unreliable. The crew used the Sun as a
navigation point to guide the crippled craft back to Earth. The Lunar Module 'lifeboat'
procedure had actually been created during a training simulation in the
simulator not long before the flight of Apollo 13.
Moon Landing Scrubbed
The damage done to the Command Space Module meant that the planned Moon-landing at the Fra
Mauro Highlands had to be scrubbed.
Fighting for their lives with help from Mission Control, the crew circled the
Moon and headed back to Earth, using the limited oxygen and power available in
the Lunar Module Aquarius to stay alive.
Plan to return to Earth
To return the crew to Earth as quickly and safely as possible, only a single
pass around the Moon was made, in what is called a free return trajectory, which
uses the Moon's gravity to "slingshot" the spacecraft back to Earth. To enter
this trajectory, a significant course correction was required. This would
normally have been a simple procedure, using the SM propulsion engine, but the
flight controllers did not know exactly how much damage the service module had
taken and did not want to risk firing the main engine. Therefore the course
correction was performed by firing the Lunar Module's descent engine, an option settled
upon after extensive discussion among the engineers on the ground. The initial
manoeuvre to change to a free return trajectory was made within hours of the
accident. After passage around the Moon, the descent engine was fired again in
order to accelerate the spacecraft's return to Earth. Afterwards, only one more
descent engine burn was required, for a minor course correction.
Because of the severe electrical power limitations following the explosion,
no live TV broadcasts were made from the craft for the remainder of the mission;
network commentators used models and animated footage to illustrate their
Apollo 13's Returning to Earth
As the time for re-entry into Earth's atmosphere approached, NASA took the
unusual step of jettisoning the Service Module before the Lunar Module, so
pictures of the SM could be taken for later analysis. When the crew saw the
damaged service module, they reported that the access panel covering the oxygen
tanks and fuel cells, which extended the entire length of the Module's body, had
been blown off.
Due to reduced temperatures on the return leg of the mission, there was
extensive water condensation in the Command Module. There was some fear that this
condensation could seriously damage the electronics of the Command Module by
causing a short circuit. Until the electronics were activated, it was impossible
to know whether this would occur. The equipment worked normally when activated,
however, partly due to the extensive design modifications made to the CM after
the fire aboard Apollo 1.
The lunar module burned up in Earth's atmosphere on 17 April, 1970,
having been targeted to enter over the Pacific Ocean to reduce the possibility
of contamination from a SNAP 27 radioisotope thermoelectric generator (RTG) on
board. After re-entry, the crew splashed down at 21°38′S, 165°22′W, SE of
American Samoa, Pacific Ocean and 6.5 km (4 miles) from the retrieval ship,
U.S.S. Iwo Jima almost four days after the explosion on April 17.
The crew returned unharmed to Earth, although Haise had a urinary tract
infection, as a result of the scarcity of potable water on the damaged ship and
the difficulty of urine disposal. The crew was instructed to store urine and
other waste products on board instead of dumping them into space, to avoid
altering the trajectory of the spacecraft.
Cause of the Accident
The explosion on Apollo 13 led to a lengthy investigation of the
underlying cause. Based on detailed manufacturing records and logs of mission
problems, the oxygen tank failure was tracked to a combination of multiple
faults. Individually, they were not critical problems, but together they led to
near disaster for Apollo 13.
The Apollo 13 mission has been called a 'Successful Failure', in that the
astronauts were successfully returned safely to Earth despite not landing on the
moon. Apollo 13 was supposed to land in the lunar region of Fra Mauro, but this
landing site was later reassigned to Apollo 14.
Although the explosion forced the mission to be aborted, the crew was
fortunate that it occurred on the first leg of the mission, when they had a
maximum of supplies, equipment, and power. If the explosion had occurred while
in orbit around the Moon or on the return leg after the LM had been jettisoned,
the crew would have had a significantly smaller probability of survival.
Did you know?
Apollo 13 Mission Patch
three flying horses of Apollo's chariot across the sky, the motto “Ex luna,
scientia” (from the Moon, knowledge) and the number of the mission in Roman
numerals (APOLLO XIII). It is one of two Apollo insignias (the other being
that of Apollo 11) not to include the names of the crew (which was
fortunate, considering that Ken Mattingly, one of the original crew members,
was replaced not long before the mission began). It was designed by artist
Lumen Winter, who based it on a mural he had done for the St. Regis Hotel in
New York; the mural was later purchased by actor Tom Hanks, who portrayed
Lovell in the movie Apollo 13 and now is on the wall of a restaurant in
Chicago, owned by Lovell's son.
* Apollo 13 film was released in 1995. It was directed by Ron
Howard and starred Tom Hanks, Bill Paxton, and Kevin Bacon as the astronauts. It
made the saying "Houston, we have a Problem" famous.
* Famous Mis-Quote: "Houston, we have a problem". Actual quote:
Houston, we've had a problem here", uttered by Swigert to ground. Lovell then
uttered this similar phrase: "Houston, we've had a problem'.
John Swigert (CMP)
=> "Okay, Houston, we've had a problem here".
Jack Lousma (CAPCOM)
=> "This is Houston. Say again, please".
James Lovell (Commander)
=> "Uh, Houston,
we've had a problem".
James Lovell (Commander)
=> "We've had a
Main B Bus undervolt".
Jack Lousma (CAPCOM)
=> "Roger Main B undervolt".
Jack Lousma (CAPCOM)
=> "Okay, stand by thirteen, we're looking at it".
* Is 13 a bad luck number? The mission started on April 11, 1970 (11/4/70
UK, 4/11/70 USA: 1 + 1 + 4 + 7 = 13) at 13:13 CST, the problems began on April
13 and the mission was called Apollo 13. Since then NASA has never had another
spacecraft numbered 13.
* 'Houston, We've Got a Problem', a
1974 movie while set around the Apollo 13
incident is a fictional drama about the crises faced by ground personnel when
the emergency disrupts their work schedules and places additional stress on
* Sega produced an Apollo 13 pinball machine (based on the 1995 movie rather
than directly on the mission itself), featuring a 13-ball multiball.
* The Apollo 13 Mission Operations Team was awarded the Presidential Medal of
Freedom for their actions during the mission, as were the astronauts.
* The Odyssey command module is currently on display at the Kansas
Cosmosphere and Space Center, Hutchinson, Kansas.