The MaTH-Robotics Team met on Friday, August 10, to watch the movie Apollo 13. Three families showed up to participate - the Abbotts, the McDonald family, and the Woelfel family. This movie is a precursor to the BEST activity at Tuesday's meeting, and also to the speaking engagement by Mr. Jerry Woodfill, who was one of the Apollo 13 mission controllers. The coaches of the team strongly encourage all parents to watch this movie with their children before the next meeting.
Plot summary from IMDB
It had been less than a year since man first walked on the Moon, but as far as the American public was concerned, Apollo 13 was just another "routine" space flight--until these words pierced the immense void of space: "Houston, we have a problem." Stranded 205,000 miles from Earth in a crippled spacecraft, astronauts Jim Lovell, Fred Haise and Jack Swigert fight a desperate battle to survive. Meanwhile, at Mission Control, astronaut Ken Mattingly, flight director Gene Kranz and a heroic ground crew race against time--and the odds--to bring them home.
From Wikipedia:
As the spacecraft was on its way to the Moon, at a distance of 321,860 kilometers (199,990 mi) from Earth, the number two oxygen tank, exploded. Mission Control had requested that the crew stir the oxygen tanks. 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 limit, and causing the tank to explode. The cause of the explosion was unknown at the time, however, and the crew and Houston conjectured that a meteoroid had struck the SM or even the Lunar Module (LM).
This explosion caused damage to other parts of the Service Module, including, critically, the number one oxygen tank. Because the Command/Service Module (CSM) relied on the oxygen tanks to generate electricity, damage to number one tank meant that very little power was available for the spacecraft. The Command Module (CM) contained batteries for use during re-entry, after the SM was jettisoned, but these would only last about ten hours. Because this power needed to be saved for re-entry, the crew survived by using the LM, still attached to the CSM, as a "lifeboat". The LM "lifeboat" procedure had actually been created during a training simulation (in the simulator) not long before the flight of Apollo 13.[8](Lovell and Kluger 83-87)
The damage done to the CSM meant that the planned Moon-landing at the Fra Mauro Highlands had to be scrubbed. 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 LM's descent engine, an option settled upon after extensive discussion among the engineers on the ground. The initial maneuver 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 for a PC+2 burn (PeriCynthion + 2 hours) in order to accelerate the spacecraft's return to Earth. Afterwards, only one more descent engine burn was required, for a minor course correction.
This is the part that is like Robotics:
Considerable ingenuity under extreme pressure was required from both the crew and the flight controllers to work out how to jury rig the craft for the crew's safe return, with much of the world watching the developing drama on television. (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 coverage).
A major challenge in keeping the crew alive was that the LM "lifeboat" was only equipped to sustain two people for two days, but had to sustain three people for four days. The lithium hydroxide canisters available for the LM'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 LM's receptacle. An adapter then had to be fabricated from materials in the spacecraft. The astronauts called it the "mailbox."[9]
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 CM. 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.
