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“Houston, we have a problem.” As an insulating tape and hundreds of NASA specialists rescued “Apollo 13”

The winged phrase from the title in the original sounded more optimistic: “Houston, we had a problem . ” Apparently, the astronauts of Apollo-13 were looking for positive things, although they had hardly more difficulties for one mission than for the entire space program of the United States. The history of this flight is amazing from all sides. This is a living example of how common efforts, ingenuity and the most insane ideas helped to avoid a catastrophe and get out of an almost hopeless situation.

After the landing of the mission Apollo 11 mission to the moon in July 1969, all attention was given to Neil Armstrong and Buzz Aldrin, slightly less to Michael Collins. But not every person will say from the run how many expeditions there were to the moon: the next Apollo launches have already lost the novelty effect and were perceived more mundane. However, the third flight was a good reminder that even with the fulfilled scheme everything can go wrong. Mission “Apollo 13”, fully confirming its unhappy figure, was accompanied by a heap of problems before the start.

There is a contact

It all started with the replacement of oxygen tanks in 1968. First they were supposed to be put on Apollo 10 at first, but then they decided to take other tanks, and these ones should be modernized and used in future missions. They were useful only during the preparation of “Apollo 13”.

Oxygen tank of Apollo 13. Image: flickr.com

Then the human factor manifested itself during a routine operation: experts forgot to unscrew the bolt fastening, and the tank fell from a tiny height – about 5 centimeters. The components of the spaceship are things as delicate as the hull of a nuclear reactor , so even such an incident was recorded in the report. The tank itself was checked, but no damage was found. Nevertheless, this did not save us from big problems.

The spring of 1970 has come. NASA specialists have twice successfully sent astronauts to the Moon, and the third flight was planned to be conducted according to the tested scheme. For the mission, the launch vehicle Saturn-5 was used, which was supposed to put the Odyssey command module into orbit, the service compartment and the lunar module Aquarius attached to it. Shortly before the flight scheduled for April 11, a general dress rehearsal was held. A nuance was discovered: oxygen in one of the tanks did not merge, as it should. At NASA, they decided that the snag was in the drainage system element, which was damaged after the fall two years ago.

Specialists came up with a new way to empty the tank – to heat up oxygen so that it simply evaporated through the ventilation system. The drain system was used only for ground tests, in flight it was not needed. Replacing the tank for a new one would shift the mission start for a month, and this at best.

Launch vehicle Saturn V, which was used for the program “Apollo”. Image: tokkoro.com

At NASA, it was felt that there was no such need – once the element was not used, it did not matter if it was damaged. It can not be said that the agency neglected the safety of the crew: the commander of the mission was informed of the situation, but when he learned that the problem would not affect the flight, he agreed to start with the damaged tank for the sake of compliance with the schedule. In fact, the tank has already caused an indirect problem: it was necessary to remove oxygen in an abnormal way, using an internal heater.

Another mistake made itself felt here, much more serious. But they will notice it only during the investigation after the astronauts return to Earth. The on-board network of the module provides a voltage of 28 volts. However, the voltage of ground equipment, which is used for system checks, is 65 volts. The confusion was due to the fact that the Odyssey was done by one company, and the tanks for it were different.

The equipment was replaced with the correct one everywhere except the contacts on the thermostats in the tank. They remained designed to operate at 28 volts. Neither NASA nor the contractors noticed this.

When working at increased voltage, contacts melted and did not open when reaching 27 degrees Celsius, as they should. In this case, there was a backup option for disabling – manually. But here there was a nuance: the arrow indicator could not show more than 27 degrees. Nobody assumed that the temperature in the tank would reach even such values. While the device displayed 27 degrees, the actual temperature exceeded 500 degrees Celsius. Because of this, the Teflon insulation of the wires melted.

Personnel permutations and engine failure

The next problem occurred a few days before the start, this time with the crew. Thomas Mattingly could pick up rubella, and NASA was reinsured, replacing the astronaut with John Sweigert. For him and Fred Hase, this was the first space flight, and mission commander James Lowell by that time already tripled outside the Earth.

Fred Hayes, John Sweigert, James Lowell. Image:  nasa.gov

Finally, on the afternoon of April 11, 1970, Saturn-5 broke away  from the site at Cape Canaveral. Already after five and a half minutes after the start, a new misfortune occurred: the central engine disconnected itself. NASA decided to continue the flight, compensating for the loss of traction by the longer operation of the other four engines. As it turns out later, the main engine was shut down due to fluctuations in the combustion chamber – the automatics stopped supplying fuel for safety reasons. Compared with the further problems of the Apollo 13, it was a trifle.

In flight, the crew needed to mix the contents of the oxygen tanks approximately once a day. This is the standard procedure: the gas under flight conditions is stratified, which is why the sensors show incorrect values ​​of the reserves. On the third day of the flight, about 16 seconds after the fans were turned on inside the tanks, the astronauts felt a strong blow. Afterwards, the alarm was activated due to the fallen voltage of the on-board power supply system. Oxygen tank number 2 explosion also damaged tank number 1, and two fuel cells of the three out of order. Sweigert gets in touch with NASA and says that same catch phrase.

The situation was unenviable. The astronauts saw a stream of gas that gushed from the oxygen tank. She gave the ship a reactive force, rotating it. The leak could not be stopped, and NASA decided to resort to the extreme option – go to use the lunar module, disabling the main one. The blessing at designing “Aquarius” such possibility was pawned.

The picture was taken by the crew of Apollo-13 during the flight of the moon. Image: wikimedia.org

Meanwhile, the center for flight control worked out different scenarios for the return of astronauts to Earth: it became clear that there could be no question of landing on the moon, the main task was simply to return the crew home. Globally, the options were divided into a return using the usual “Apollo” trajectory with or without the flight of the Moon. All ideas were risky, and NASA stopped on the most secure in the light of the situation. Astronauts had to fly around the moon and point the moon engine to correct the trajectory.

Mug of water per day

Oxygen in the crew was in abundance – astronauts breathed air from the reserves of “Aquarius”. But there was a problem with water and energy: the crew had to save a lot of liquid, but only the most necessary systems remained in operation. The heating elements were not relevant to them, and the temperature in the module fell to about 5 degrees Celsius. Astronauts moved little and began to freeze, besides the state of health of the crew deteriorated due to stress, lack of water and sleep. During the expedition Lowell lost 6.3 kilograms, Hayes became very ill. Each crew member reduced the consumption of water to just six ounces (170 grams) per day – this is the fifth part of the norm. There was no other option: the fluid was required to cool the systems on the ship.

Newspapers then did not exaggerate: the crew of the Apollo-13 was really on the brink of survival. Image: madison.com

The crew had another problem: although they had enough oxygen, carbon dioxide accumulated in the module. His concentration continued to grow, because in the compartment instead of two people, as originally planned, there are three. The situation became serious: the device for measuring carbon dioxide already showed a value of 13 points, and reaching a concentration of 15 points would lead to dizziness, nausea and loss of orientation. In this case, cartridges with lithium hydroxide were provided – it is used to absorb CO 2 in gas masks that are on spaceships. But there was anecdotal situation: the necessary connector in the lunar module is round, and the output of the cartridge for the Odyssey is square.

Unification of interfaces was not carried out for the reason that such a scenario could not be foreseen – the situation was too incredible. Smart engineers NASA rescued astronauts life: experts selected the items that were at the disposal of “Apollo 13”, and built a sealed adapter of hoses from a spacesuit, cardboard, insulating tape and bags. Then instructions were given to the crew, and they assembled a similar device.

The resulting adapter in NASA was called a “mailbox”. Image: nasa.gov

When it seemed that with “Apollo-13” there were in general all the ills possible, in the lunar module the battery cell exploded. In the future it will be established that this was due to the sparks in the accumulation of oxygen and hydrogen. The astronauts were lucky again: the surviving power systems continued to work.

The crew had to solve the last problem – to bring the module to an acceptable path for landing, so that it would not burn out when entering the atmosphere. The astronauts used low-power engines for orienting the lunar module, which were not designed for use in such a scenario.

Shortly before returning to the planet, Lowell, Hayes and Sweigert moved the ballast to Odyssey: landing was implied with samples of the lunar rock, and it was necessary to simulate the weight of the calculations. After this, the crew disconnected the service module, in which an explosion of the oxygen tank occurred. Only then did they see the scale of the explosion: the missing panel, the missing tank, the damaged engine nozzle. It became clear that the option of returning to Earth with a direct turn of the ship, without flying around the moon, would almost certainly lead to the death of the crew.

Damaged service module. Image: nasa.gov

Then it was required to disconnect the lunar module and prepare for landing. Almost for the first time in the whole mission the events went as it should: the navigation worked properly, all the parachutes opened, and on April 17 the crew of Apollo-13 was on its home planet. The exhausted astronauts quickly picked up a nearby ship.


On the one hand, the abundance of malfunctions revealed many flaws, and on the other – showed that even with the most serious damage and failure of many important systems, the crew can be safely returned to Earth.

Module “Odyssey” after returning to Earth. Image:  wikimedia.org

None of the astronauts of the Apollo 13 flew into space. James Lowell never landed on the Moon, Fred Hayes only participated in the tests of the prototype shuttle – the ship Enterprise. John Sweigert was elected to the US Congress, but he died in 1982, without having had time to taste political life. Thomas Mattingly, who was removed from the Apollo 13 at the last minute due to a possible rubella, did not pick up the disease. Later, he made three space flights. In total NASA astronauts made six landings on the Moon.

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