A perilous situation
A perilous situation
Bracco shared an interesting story involving the Apollo 13 crew in a perilous situation in outer space and the heroic efforts of the Grumman designers along with NASA Mission Control experts to avert a lethal situation and safely return these men to Earth. At five and a half minutes after liftoff, astronauts Jack Swigert, Fred Haise, and James Lovell felt a little vibration. The center engine of the massive Saturn S-II stage shut down two minutes early, causing the remaining four engines to burn 34 seconds longer than planned. The S-IVB third stage was forced to burn nine seconds longer to put Apollo 13 in orbit.
At 55 hours and 46 minutes, as the crew finished a 49-minute TV broadcast showing how comfortably they lived and worked in weightlessness, Lovell said, "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 LEM] and get back for a pleasant evening in Odyssey [the command module]. Good night." Nine minutes later, oxygen tank number 2 blew up, causing oxygen tank number 1 to also fail. Approximately 200,000 miles from Earth, the Apollo 13 command module's normal supply of electricity, light, and water was lost.
The message came in the form of a sharp bang and vibration. Swigert saw a warning light that accompanied the bang and said, "Houston, we've had a problem here." Lovell came on and told the ground that it was a main B bus undervolt. The time was 2108 hours on April 13.
Next, the warning lights indicated the loss of two of Apollo 13's three fuel cells, which were the spacecraft's prime source of electricity. With warning lights blinking, one oxygen tank appeared to be completely empty, and there were indications that the oxygen in the second tank was rapidly being depleted. The third lunar landing attempt mission was aborted after rupture of the service module oxygen tank.
Power was a concern. There were 2181 ampere hours in the LEM batteries. Ground controllers carefully worked out a procedure that enabled LEM power to be used to charge the command module batteries.
With the power-producing service module damaged due to an explosion, an innovative idea involving a roll of duct tape and a technical manual saved the crew from carbon-dioxide poisoning. The crew was instructed to rip out plasticized pages of an onboard manual and get the duct tape ready so they could attach the command module's lithium hydroxide canisters (used to remove carbon dioxide from the cabin atmosphere) to the LEM environmental system using the square canisters from the command module. All noncritical systems were turned off, and energy consumption was reduced to a fifth of normal. Twenty percent of the LEM electrical power was left when Aquarius was jettisoned.
As part of an electrical close call during the mission, one of the control-module batteries vented with such force that it momentarily dropped off the line. Had the battery failed, there would be insufficient power to return the ship to Earth. Luckily, there was no failure.
Grumman had greatly overdesigned the LEM so that in this situation it was able to keep the crew alive until the ship could circle around the moon in a "sling-shot" path to propel it back toward Earth for a safe entry into the atmosphere and safe splashdown in the ocean. The Grumman designers were sure of the LEM's capabilities. The mission was classified as a "successful failure" because of experience gained while rescuing the crew.