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Home , Ken Mattingly

NEWMARKET U3A: WINGS, WHEELS & WATER Presentation for April 2020 Due to the Coronavirus, this month’s presentation is designed for home study PICTURES: LEFT the Service Module showing damage from the explosion. RIGHT: The three ; James Lovell, John Swigart and

Introduction & Overview Apollo 13 was the seventh crewed mission in the Apollo space program and the third meant to land on the Moon. The craft was launched from Kennedy Space Centre on April 11, 1970, but the lunar landing was aborted after an oxygen tank in the service module (SM) failed two days into the mission. The crew instead looped around the Moon, and returned safely to Earth on April 17. The mission was commanded by with as command module (CM) pilot and Fred Haise as lunar module (LM) pilot. Swigert was a late replacement for Ken Mattingly, who was grounded after exposure to rubella. The accident was caused by ignition of damaged wire insulation inside an oxygen tank as it was being rou- tinely stirred. The oxygen in the tank was in liquid form and needed to be stirred with a large sort of elec- tric whisk from time to time to ensure that all the contents of the tank were at an even temperature asnd not causing damage to the tank itself which was lined with Teflon. Liquid oxygen and Teflon are both very volatile and unpredictable materials. Without oxygen, needed both for breathing and for generating elec- tric power, the SM's propulsion and life support systems could not operate. The CM's systems had to be shut down to conserve its remaining resources for re-entry, forcing the crew to transfer to the LM as a lifeboat. With the lunar landing cancelled, mission controllers worked to bring the crew home alive. Although the LM was designed to support two men on the lunar surface for two days, Mission Control in Houston im- provised new procedures so it could support three men for four days. The crew experienced great hardship caused by limited power, a chilly and wet cabin and a shortage of drink- able water. There was a critical need to adapt the CM's car- bon dioxide removal system to work in the LM; the crew and mission controllers were successful in improvising a solution. The astronauts' peril briefly renewed interest in the ; tens of millions watched the splashdown in the South Pacific Ocean by television.

LEFT: A beaker of liquid oxygen

An investigative review board found fault with pre-flight testing of the oxygen tank and the fact that Teflon was placed inside it. The board recommended changes, including minimizing the use of potentially combustible items inside the tank; this was done for . The story of Apollo 13 has been drama- tized several times, most notably in the 1995 film Apollo 13.

Background to the Apollo Programme In 1961, U.S. President John F. Kennedy challenged his nation to land an on the Moon by the end of the decade, with a safe return to Earth. NASA worked towards this goal gradually, sending astro- nauts into space during the Mercury and Gemini Projects, in preparation for the Apollo programme. The goal was achieved with , which landed on the Moon on July 20, 1969. and walked on the lunar surface while Michael Collins orbited the Moon in Command Module Colum- bia. The mission returned to Earth on July 24, 1969, fulfilling Kennedy's challenge. NASA had bought fifteen rockets to achieve the goal; at the time no one knew how many mis- sions it would take to get top the Moon. As the project was successful in 1969 with the sixth Saturn V on Apollo 11, nine rockets remained available for a total of ten landings. After the excitement of Apollo 11, the general public gradually grew apathetic towards the space programme, losing interest as the missions continued successfully with . In the media build up towards the launch of Apollo 13, the public showed little interest and even less excitement apart from the possibilities afforded by the unlucky num- ber 13. Congress continued to cut NASA's budget; Apollo 20 was cancelled. Despite the successful lunar landings of Apollos 11 & 12, the missions were considered so risky that astro- nauts could not afford life insurance to provide for their families if they died in space. Planning for a centralized Mission Control began in 1959, led by Dr Christopher C. Kraft, who became NASA's first flight director. During 's Mercury Friendship 7 flight in February 1962, Kraft was overruled by NASA managers. He was vindicated by post-mission analysis, and so implemented a rule that during the mission, the flight director's word was absolute—to overrule him, NASA would have to fire him on the spot. Apollo Flight directors had a one sentence job description, "The flight director may take any actions necessary for crew safety and mission success.” He worked for over a decade in aeronautical research before being asked in 1958 to join the Space Task Group, a small team entrusted with the responsibility of putting America's first man in space. Assigned to the flight operations division, Kraft became NASA's first flight director. He was on duty during such historic missions as America's first crewed spaceflight, first crewed orbital flight, and first spacewalk. Kraft was responsible for shaping the organization and culture of NASA's Mission Control. In 2011, the Mission Control Centre building was

Dr Christopher Kraft: NASA’s first Flight Director. LEFT: Mission Control Oper- ations Room just before the Apollo 13 accident. The astronaut on the TV screen is Fred Haise, pilot of the Lunar Module

Mission Insignia, Call-signs and Motto The Apollo 13 mission insignia depicts the Greek god of the Sun, Apollo, with three horses pulling his char- iot across the face of the Moon, and the Earth seen in the distance. This is meant to symbolize the Apollo flights bringing the light of knowledge to all people. The mission motto is Ex luna, scientia (From the Moon, knowledge). In choosing it, Lovell adapted the motto of his alma mater, the Naval Academy, Ex scientia, tridens (From knowledge, sea power). On the patch, the mission number appeared in Roman numerals as Apollo XIII. It did not have to be modified after Mattingly's replacement by Swigert since it is one of only two Apollo mission insignia—the other being Apollo 11—not to in- clude the names of the crew. It was designed by artist Lumen Martin Winter, who based it on a mural he had painted for The St. Regis Hotel in New York City. The mural was later purchased by actor Tom Hanks, who portrayed Lovell in the movie Apollo 13, and is now in the Captain James A. Lovell Federal Health Care Center in Illinois. The mission's motto was in Lovell's mind when he chose the call sign Aquarius for the lunar module, taken from Aquarius, the bringer of water. Some in the media wrongly reported that the call sign was taken from a song from the musical Hair. The command module's call sign, Odyssey, was chosen not only for its Homeric association but to refer to the recent movie, 2001: A Space Odyssey, based on a short story by science fiction author Arthur C. Clarke. In his book, Lovell indicated he chose the name Odyssey because he liked the word and its definition: a long voyage with many changes of fortune. The Apollo 13 Mission The Saturn V rocket used to carry Apollo 13 to the Moon was numbered SA-508, and was almost iden- tical to those used on Apollos 8 to 12. Including the spacecraft, the rocket weighed in at 2,949,136 kilo- grams. The S-IC stage's engines were rated to gen- erate 440,000 newtons less total thrust than Apollo 12's, in preparation for future, heavier loads. Ex- tra propellant was carried as a test since future J missions to the Moon would require more propel- lant for their heavier payloads. This made the vehi- cle the heaviest yet flown by NASA and Apollo 13 was visibly slower to clear the launch tower than earlier missions.

The Apollo 13 spacecraft consisted of Command Module 109 and Service Module 109 (together CSM- 109), called Odyssey, and Lunar Module 7 (LM-7), called Aquarius. Also considered part of the spacecraft were the launch escape system which would propel the command module (CM) to safety in the event of a problem during lift-off, and the Spacecraft–LM Adapter, numbered as SLA-16, which housed the lunar module (LM) during the first hours of the mission.

This is the form in which the Apollo moon shots travelled to the moon. Once on the way out of Earth orbit the Com- mand & Service Modules separated from the Lunar module, turned round and attached it again as in the picture above. Launch and trans- lunar injection

The mission was launched at the planned time, 2:13:00 pm EST on April 11. An anomaly occurred when the second-stage, centre engine shut down about two minutes early. This was caused by severe pogo oscillations. Starting with , the vehi- cle's guidance system was designed to shut the en- gine down if these oscilla- tions started. Pogo oscilla- tions had occurred on Ti- tan rockets (used during the Gemini program) and on previous Apollo mis- sions, but on Apollo 13 they were made very much worse by the move- ment of the liquid fuels in their tanks. Engineers were ready to sort this out but there wasn’t enough time before the mission left. A post-flight investi- gation revealed the engine was one cycle away from catastrophic failure. In spite of the shutdown, the four other engines and the S-IVB third stage burned longer to compensate, and the vehicle achieved very close to the planned circu- lar 190 kilometres parking orbit, followed by a trans- lunar injection (TLI) about two hours later, setting the mission on course for the Moon. Pogo oscillations are called that because they A post-flight investigation revealed the engine was are rather like the up-and-down movement of one cycle away from catastrophic failure. In spite a pogo stick and they are started independent- of the shutdown, the four outboard engines and ly in the propellant liquid by its own flow. Ra- the S-IVB third stage burned longer to compensate, ther a complicated business but if left to carry and the vehicle achieved very close to the planned on they can become very dangerous. The only circular 190 kilometers (100 nmi) parking orbit, fol- real way to stop them is to shut down the en- lowed by a translunar injection (TLI) about two gine causing the vibrations. Of course if this is hours later, setting the mission on course for the done at the wrong moment then the whole Moon. mission and the crew might be in danger. About 2.25 days into the mission as the crew were Apollo 13 was going to have dampers fitted carrying out routine activities – approaching that would stop these oscillations but there 56:00:00 hours, Apollo 13 was about 180,000 nauti- wasn’t time to get them done. cal miles (210,000 mi; 330,000 km) from Earth. Haise was completing the shutdown of the LM after testing its systems while Lovell stowed the TV cam- era. The pressure sensors in one of the oxygen tanks had been erratic so the astronauts were asked to switch on the stirring system. 95 seconds after that the astronauts heard a loud bang.

The Russian H2 Super-Heavy Lift launch vehicle. All four attempted launches blew up on take-off, the second one falling back on to its launch pad and causing the largest non-nuclear explo- sion ever recorded. These failures were due in large part to pogo oscillation.

RIGHT: The launch of Apollo 13 from Ken- nedy Space Centre on 11 The Accident and Aftermath "Okay, Houston, we've had a problem here," were the words actually spoken first by Swigert but history reports it as “Houston, we have a problem”, words scripted into all the dramatic versions of the story. There had been a loud bang, looking out of the windows there was debris of all shapes and sizes outside and a cloud of gas escaping from the side of the Command Module. The explosion had been caused by an electrical fault in the oxygen tank when Swigert switched on the stirring fan. It was a human error caused by poor wiring in the tank. The cable to the motor was not properly shielded and when the current was switched on, a spark crossed from the cable to the casing of the motor. In the oxygen-rich atmosphere the result was a sudden disastrous explosion. One of the tanks was destroyed, the second badly damaged. The Command and Service modules had only a tiny reserve tank left. This would not be enough to provide power to the engine and to all the controls as well as for the crew to breathe for the three days it would take to go round the moon and return to Earth. On Apollo 10 there had been a training session which used the Lunar Module as a ‘lifeboat’ to get the crew home and this is where all the ground crews started looking. There was oxygen in the Lunar Mod- ule—enough for two men for 54 hours, not enough for three men for three days. And certainly not enough to provide electricity. Another difficulty was that the production of electricity produced water as a by-product for drinking and cooling. No electricity meant no water. The astronauts were allowed 0.2 litres per day. They could only survive in the lunar module if the oxygen could be made to last. The Command Module had ‘scrubbers’ which cleaned the CO2 out of the air so it could be reused. The Lunar Module did not have these. If the oxygen tanks in the Lunar Module could use the Scrubbers in the Command module they might survive. In an exercise worthy of Blue Peter, the astronauts, sup- ported by the ground crews on Earth designed a Heath Robinson arrangements to allow the used air to be piped through the Command Module scrubbers and returned for re-use. Lengths of tube from their space suits, plastic covers from the instruction files and yards of Duck Tape were used to create the apparatus in the photo on the left. There was no heating available in the Lunar Module and the temperature fell to 3.0 degrees Celsius. LEFT: Lovel in the freezing LM

There are other considerable difficulties that were extremely complicated. The Command Module power was shut down completely by the explosion and there was great concern that everything might not return to normal when powered up for re-entry. Navigation had to be done manually to set courses for return to earth and this was difficult because all the debris out- side obscured the stars, apart form the sun. The last problem to be solved was how to separate the Lu- nar Module and move it a safe distance away from the Command Module just before re-entry. The normal proce- dure, in , was to release the LM then use the service module's engine to pull the Command and Service Module away, but by this point the SM had already been released. , manufacturer of the LM, assigned a team of University of Toronto engineers, led by senior sci- entist Bernard Etkin, to solve the problem of how much air pressure to use to push the modules apart. The astronauts Nobody believes me, but during this six-day applied the solution, which was successful. The LM re- odyssey we had no idea what an impression entered Earth's atmosphere and was destroyed, the re- Apollo 13 made on the people of Earth. We maining pieces falling in the deep ocean. Apollo 13's final never dreamed a billion people were follow- midcourse correction had addressed the concerns of the ing us on television and radio, and reading Atomic Energy Commission, which wanted the cask con- about us in banner headlines of every news- paper published. We still missed the point on taining the plutonium oxide intended for an experiment on board the carrier Iwo Jima, which picked us the moon, to land in a safe place. The impact point was up, because the sailors had been as remote over the Tonga Trench in the Pacific, one of its deepest from the media as we were. Only when we points, and the cask sank 10 kilometres (6 mi) to the reached Honolulu did we comprehend our bottom. impact: there we found President Nixon and [NASA Administrator] Dr. Paine to meet us, along with my wife Marilyn, Fred's wife Mary (who being pregnant, also had a doctor along just in case), and bachelor Jack's parents, in lieu of his usual airline stewardesses. Worldwide interest in the Apollo program was reawakened by the incident; television cover- age of which was seen by millions. President Nixon cancelled appointments, phoned the astronauts' families, and drove to NASA's Space Flight Center in Maryland, where Apol- lo's tracking and communications were coordi- nated.

The rescue received more public attention than any spaceflight to that point, other than Apollo 11. There were worldwide headlines, and people surrounded television sets to get the latest developments. Pope Paul VI led a congregation of 10,000 people in praying for Jack Gould of The New York Times stated that Apollo 13, the astronauts' safe return; ten times that "which came so close to tragic disaster, in all probability number offered prayers at a religious festival united the world in mutual concern more fully than an- in India. The United States Senate on April 14 passed a resolution urging businesses to pause other successful landing on the Moon would have". at 9:00 pm local time that evening to allow for employee prayer.