The Saturn 5 launching Apollo 11
I had always thought that the Mercury, Gemini and Apollo spacecraft and rockets were designed and built sequentially. It turns out they were built roughly in parallel, with each mission providing input to the capsule design of the next flights. The rockets were designed in parallel.

While the Mercury and early Gemini used converted ICBM launchers, the later Gemini missions and all of the Apollo missions used rockets that were invented for the purpose. By the time of the moon fly-bys and landings, we had invented technology never seen before, with launchers as big as the Washington Monument.

Apollo was the program, that, taking off from the difficult successes of Mercury and Gemini, was to send men to the moon, and bring them back safely.

How did they do this? This section tells that story.

BACKGROUND AND POLITICS

President Eisenhower
Dwight David “Ike” Eisenhower (October 14, 1890 – March 28, 1969) was the 34th President of the United States from 1953 until 1961 and a five-star general in the United States Army. During the Second World War, he served as Supreme Commander of the Allied forces in Europe, with responsibility for planning and supervising the successful invasion of France and Germany in 1944–45. In 1951, he became the first supreme commander of NATO.

As President, he oversaw the cease-fire of the
Korean War, kept up the pressure on the Soviet Union during the Cold War, made nuclear weapons a higher defense priority, launched the Space Race, enlarged the Social Security program, and began the Interstate Highway System. He was the last World War I veteran to serve as U.S. president.



The Apollo program was originally conceived early in 1960, during the Eisenhower administration, as a follow-up to America's Mercury program. While the Mercury capsule could only support one astronaut on a limited earth orbital mission, the Apollo spacecraft was intended to be able to carry three astronauts on a circumlunar flight and perhaps even on a lunar landing.

The program was named after the Greek god of light and archery by NASA manager Abe Silverstein, who later said that: "I was naming the spacecraft like I'd name my baby."




Sarurn V diagram
The Low Earth orbit (LEO) rockets could be rebuilt ICBM launchers, as to achieve LEO, required the rockets to reach 17,500 mph. This was the sole -- sinister purpose -- of the ICBM. To reach "Escape Velocity" -- to leave Earth's Gravity, a whole new type of rocket had to be built that would be able to reach at least 25,000 mph. The ICBMs were perfect for LEO -- that's what they were designed for.

But there was no technology to reach Escape Velocity. It was going to have to be invented. That's why there was such an early start. While NASA went ahead with planning for Apollo, funding for the program was far from certain, particularly given Eisenhower's equivocal attitude to manned spaceflight.



John F. Kennedy
In November 1960, John F. Kennedy was elected President after a campaign that promised American superiority over the Soviet Union in the fields of space exploration and missile defense. Using space exploration as a symbol of national prestige, he warned of a "missile gap" between the two nations, pledging to make the US not "first but, first and, first if, but first period."

Despite Kennedy's rhetoric, he did not immediately come to a decision on the status of the Apollo program once he was elected President. He knew little about the technical details of the space program, and was put off by the massive financial commitment required by a manned moon landing.


NASA Adminitrator James T. Webb
When NASA Administrator James Webb requested a thirty percent budget increase for his agency, Kennedy supported an acceleration of NASA's large booster program (the Saturn launchers) but deferred a decision on the broader issue.





Yuri Gagarin - Ю́рий Алексе́евич Гага́рин
On April 12, 1961, Soviet cosmonaut Yuri Gagarin became the first man to fly in space, reinforcing American fears about being left behind in a technological competition with the Soviet Union. At a meeting of the US House Committee on Science and Astronautics held only one day after Gagarin's flight, many congressmen pledged their support for a crash program aimed at ensuring that America would catch up.



Vice President Lyndon B. Johnson
Kennedy, however, was circumspect in his response to the news, refusing to make a commitment on America's response to the Soviets. On April 20 Kennedy sent a memo to Vice President Lyndon B. Johnson, asking Johnson to look into the status of America's space program, and into programs that could offer NASA the opportunity to catch up.

Johnson responded on the following day, concluding that "we are neither making maximum effort nor achieving results necessary if this country is to reach a position of leadership." His memo concluded that a manned moon landing was far enough in the future to make it possible that the United States could achieve it first.


The Decision to Go to the Moon: President John F. Kennedy's May 25, 1961 speech before a Joint Session of Congress


President Kennedy addressing Congress
On May 25, 1961, Kennedy announced his support for the Apollo program as part of a special address to a joint session of Congress. This is an excerpt from President Kennedy's famous statement to the Congress:

“First, I believe that this nation should commit itself to achieving the goal, before this decade is out, of landing a man on the Moon and returning him safely to the Earth. No single space project in this period will be more impressive to mankind, or more important in the long-range exploration of space; and none will be so difficult or expensive to accomplish."

This is a video of President Kennedy's Speech

At the time of Kennedy's speech, only one American had flown in space (
less than a month earlier, and for only 18 minutes) and NASA had not yet sent a man into orbit. Even some NASA employees (including Dr. Webb) doubted whether Kennedy's ambitious goal could be met. Other than the space vehicles, remember that in 1961, there were a handful of computers in the world, with a combined computing power of less than a desktop computer of today. There is a whole discussion of the computer history in the technology section of this site.

Thus, answering President Kennedy's challenge and landing men on the moon by the end of 1969 required the most sudden burst of technological creativity, and the largest commitment of resources ($25 billion), ever made by any nation in peacetime. At its peak, the Apollo program employed 400,000 people and required the support of over 20,000 industrial firms and universities.


Following the address to Congress, President Kennedy delivered this speech at Rice University on the subject of the American space program, September 12, 1962. It's long but really worth watching as you really get a measure of the man -- his power and his humor. I've split the speech into two parts to make it more manageable.

Part 1

Part 2

If you cannot watch the video, this is the salient line that has echoed over time:

“We choose to go to the moon in this decade and do the other things, not because they are easy, but because they are hard, because that goal will serve to organize and measure the best of our energies and skills, because that challenge is one that we are willing to accept, one we are unwilling to postpone, and one which we intend to win".

As you know, President Kennedy was assassinated on November 22, 1963, and never got to see the success of his vision. To his credit, President Johnson kept Kennedy's goals, with in fact two successful human explorative missions to the moon before the end of the decade. Apollo 11 with Neal Armstrong and Buzz Aldrin landed on July 20, 1969 (yes -- this year is the 40th anniversary), and Apollo 12 with Pete Conrad and Alan Bean landed on November 19, 1969. Both crews spent about a day on the surface. Later crews spent several days. This is detailed later in the site.

President Johnson was so tied up in VietNam, that he turned down the opportunity to run for re-election.

His successor, President Nixon, faced with an unpopular war, a reeling economy, and his own personality, cut the Apollo program shortly after taking office. There had been at least 20 flights planned, and the possibility of greater things, but Nixon only permitted up to Apollo 17. The Saturn launch vehicle and Apollo 18 command module were modified to take part in the first joint mission with the Soviet Union, the Apollo-Soyuz mission.

This ended the Moon Landings for the next 4 decades at least.


APOLLO TECHNOLOGY


CHOOSING A MISSION METHODOLOGY


Once President Kennedy had defined the goal, the Apollo mission planners were faced with the challenge of designing a set of flights while minimizing risk to human life and within the constraints of the existing and planned technologies, costs and astronaut skills. Four possible mission modes were considered:

Direct Ascent: A spacecraft would travel directly to the Moon, landing and returning as a unit. This plan would have required a very powerful booster, the planned Nova rocket.

Earth Orbit Rendezvous (EOR): Multiple rockets (up to fifteen in some claims) would be launched, each carrying various parts of a Direct Ascent spacecraft and propulsion units that would have enabled the spacecraft to escape earth orbit. After a docking in earth orbit, the spacecraft would have landed on the Moon as a unit.

Lunar Surface Rendezvous: Two spacecraft would be launched in succession. The first, an automated vehicle carrying propellants, would land on the Moon and would be followed some time later by the manned vehicle. Propellant would be transferred from the automated vehicle to the manned vehicle before the manned vehicle could return to Earth. This method was quickly discarded as too costly and too dangerous.

Lunar Orbit Rendezvous (LOR): One Saturn V would launch a spacecraft that was composed of modular parts. A command module would remain in orbit around the moon, while a lunar module would descend to the moon and then return to dock with the command module while still in lunar orbit. In contrast with the other plans, LOR required only a small part of the spacecraft to land on the Moon, thereby minimizing the mass to be launched from the Moon's surface for the return trip.

In early 1961, direct ascent was generally the mission mode in favor at NASA. Almost all of the engineers feared that a rendezvous -- let alone a docking -- neither of which had been attempted even in Earth orbit, would be extremely difficult in lunar orbit.

However, dissenters led by John Houbolt at Langley Research Center emphasized the important weight reductions that were offered by the LOR approach. Throughout 1960 and 1961, Houbolt campaigned for the recognition of LOR as a valid and practical option. Bypassing the NASA hierarchy, he sent a series of memos and reports on the issue to Associate Administrator Robert Seamans; while acknowledging that he spoke "somewhat as a voice in the wilderness," Houbolt pleaded that LOR should not be discounted in studies of the question.

Seamans established an ad-hoc committee in July 1961 to look at the problem -- semi-bypassing the on-going
NASA Task Force. The work of this combined committee represented a turning point in NASA's mission mode decision. While the ad-hoc committee was intended to provide a recommendation on the boosters to be used in the Apollo program, it recognized that the mode decision was an important part of this question. The committee recommended in favor of a hybrid EOR-LOR mode, but its consideration of LOR — as well as Houbolt's ceaseless work — played an important role in publicizing the workability of the approach. In late 1961 and early 1962, members of NASA's Space Task Group at the Manned Spacecraft Center in Houston began to come around to support for LOR.

The engineers at Marshall Space Flight Center took longer to become convinced of its merits, but their conversion was announced by Wernher von Braun at a briefing in June 1962. NASA's formal decision in favor of LOR was announced on July 11, 1962.

A Historic Meeting at the White House on Human Spaceflight

On 20 (or 21st, it's not clear) November 1962, President Kennedy held a meeting with
NASA Administrator James Webb, Director of the Bureau of the Budget David Bell, and several others to discuss the human spaceflight program. The meeting was prompted by a number of recent events, most notably press reports that NASA was not devoting enough attention to the Apollo lunar landing program and the possible requirement for an additional supplemental appropriation of over $400 million to NASA’s current budget.

During the meeting, Kennedy, Webb, Bell, and several members of Webb’s staff discussed issues related to human spaceflight and the need for more money. The discussion was surprisingly wide-ranging and energetic.

This meeting is a window into the role that human spaceflight played in international and domestic politics in the early 1960s. It also provides insights into the thinking of high-level government officials about spaceflight, their personal interactions, and the cooperation and conflict of their organizations.

The meeting was recorded, but the recording was not released until August 2001. It is of relatively high quality when compared to other presidential recordings from the era, but it is still rather difficult to discern and understand the various voices. A transcript of the meeting was prepared by Dwayne A. Day with assistance from Glen Swanson, John M. Logsdon, and Dr Seamans.

You can download the transcript here

Space historian James Hansen concludes that:

“Without NASA's adoption of this stubbornly held minority opinion in 1962, the United States may still have reached the Moon, but almost certainly it would not have been accomplished by the end of the 1960s, President Kennedy's target date.”

What follows is a summary of the decisions that were made from 1961 to the successful landing in July 1969. Each mission is detailed in the following pages.

However, for the scholars among you, there is the complete set of NASA transcripts of all the meetings and decisions that took place for Apollo from 1960 to 1969, with some amazing photographs, as well as some that might not be suitable for youngsters. The work was appropriately called "Chariots of Fire". This was released in 2001. There is one appendix missing (F) that I believe remains under security.

It's probably about 5-600 pages and you can
download it here. It's in a set of PDF format files.


SPACE CRAFT

The decision in favor of lunar orbit rendezvous dictated the basic design of the Apollo spacecraft. It would consist of two main sections: the Command/Service Module (CSM), in which the crew would spend most of the mission, and the Lunar Module (LM), which would descend to and return from the lunar surface.

THE APOLLO 15 COMMAND AND SERVICE MODULES




The command module (CM) was conical in shape, and was designed to carry three astronauts from launch into lunar orbit and back from the moon to splashdown. Equipment carried by the command module included reaction control engines, a docking tunnel, guidance and navigation systems and the Apollo Guidance Computer. Attached to the command module was the service module (SM), which housed the service propulsion system and its propellants, the fuel cell power system, four maneuvering thruster quads, the S-band antenna for communication with Mission Control, and storage tanks for water and air. On Apollo 15, 16 and 17 it also carried a scientific instrument package.

The two sections of the spacecraft would remain attached until just prior to re-entry, at which point the service module would be discarded. Only the command module was provided with a heat shield that would allow it and its passengers to survive the intense heat of re-entry. After re-entry it would deploy parachutes that would slow its descent through the atmosphere, allowing a smooth splashdown in the ocean.

Under the leadership of
Harrison Storms, North American Aviation won the contract to build the CSM for NASA. Relations between North American and NASA were strained during the Apollo program, particularly after the Apollo 1 fire during which three astronauts died. The cause of the accident was determined to be an electrical short in the wiring of the command module; while determination of responsibility for the accident was complex, the review board concluded that: "deficiencies existed in Command Module design, workmanship and quality control." Essential North American took the blame for work assigned and managed by a number of groups.


THE APOLLO LUNAR LANDER



The
Lunar Module (LM) (also known as Lunar Excursion Module, or LEM), was designed solely to land on the moon, and to ascend from the lunar surface to dock back with the command module. It had a limited heat shield and was of a construction so lightweight that it would not have been able to fly in Earth gravity. It carried two crew members and consisted of two stages, a descent and an ascent stage. The descent stage incorporated compartments in which cargo such as the Apollo Lunar Surface Experiment Package and Lunar Rover could be carried.

The contract for design and construction of the lunar module was awarded to
Grumman, and the project was overseen by Tom Kelly. There were also problems with the lunar module; due to delays in the test program, the LM became what was known as a "pacing item," meaning that it was in danger of delaying the schedule of the whole Apollo program. Due to these issues, the Apollo missions were rescheduled so that the first manned mission with the lunar module would be Apollo 9, rather than Apollo 8 as was originally planned.

THE BOOSTER ROCKETS

When the team of engineers led by Wernher von Braun began planning for the Apollo program, it was not yet clear what sort of mission their rocket boosters would have to support. Direct ascent would require a booster, the planned
Nova rocket, which could lift a very large payload. NASA's decision in favor of lunar orbit rendezvous re-oriented the work of Marshall Spaceflight Center towards the development of the Saturn 1B and Saturn V. While these were less powerful than the Nova would have been, the Saturn V was still much more powerful than any booster developed before—or since.



A Saturn 5 at launch

Eventually, this Saturn V rocket launched Apollo 11 and her crew on its journey to the Moon on July 16, 1969.

The Saturn V consisted of three stages (the S-1C, the S-II and (don't ask me), the S-iVB). The rocket had a self-contained
Instrument Unit which contained the booster's guidance system.

THE FIRST STAGE BOOSTER

The first stage, the S-IC, consisted of five F-1 engines arranged in a cross pattern, which produced a total of 7.5 million pounds of thrust. They accelerated the spacecraft from the launch to a speed of approximately 6000 miles per hour (2.68 km/s) in 2.5 minutes!

The S-IC First Stage Rocket Manufacturing Plant




During development, the F-1 engines were plagued by combustion instability—if the combustion of propellants was not uniform across the flame front of an engine, pressure waves could build which would cause the engine to destroy itself. The problem was solved in the end through trial and error, fine-tuning the engines through numerous tests so that even small charges set off inside the engine would not induce instability.

THE SECOND STAGE ROCKET

The second stage, the
S-II, used five J-2 engines. They burned for approximately six minutes, taking the spacecraft to a speed of 15,300 miles per hour (6.84 km/s) and an altitude of about 115 miles (185 km).




THE THIRD STAGE ROCKET

At this point the
S-IVB third stage took over, putting the spacecraft into orbit. Its one J-2 engine was designed to be restarted in order to make the translunar injection burn.





THE SATURN 1B ROCKET


The
Saturn IB was an upgraded version of the earlier Saturn I. It consisted of a first stage made up of eight H-1 engines and a second S-IVB stage which was identical to the Saturn V's third stage. The Saturn IB had only 1.6 million pounds of thrust in its first stage—compared to 7.5 million pounds for the Saturn V—but was capable of putting a command and lunar module into earth orbit. It was used in Apollo test missions and the Apollo-Soyuz Test Program. In 1973 a refitted S-IVB stage, launched by a Saturn V, became the Skylab space station.

Saturn 1B Rocket


MISSION PLANNING


In September 1967, the Manned Spacecraft Center in Houston, Texas, proposed a series of missions that would lead up to a manned lunar landing. Ten mission types were outlined, each testing a specific set of components and tasks; each previous step needed to be completed successfully before the next mission type could be undertaken.

These were:

A - Unmanned Command/Service Module (CSM) test

B - Unmanned Lunar Module (LM) test

C - Manned CSM in low Earth orbit

D - Manned CSM and LM in low Earth orbit

E - Manned CSM and LM in an elliptical Earth orbit with an apogee of 4600 mi (7400 km)

F - Manned CSM and LM in lunar orbit

G - Manned lunar landing

H - Short duration stays on the Moon with two LEVAs ("moonwalks").

J - Longer three day stays, with three LEVAs and the use of the lunar rover. Apollo 18 to 20 would have been J missions, as Apollo 15 to 17 were.

In addition, a further group of flights — the I missions — were planned, which would have been long duration orbital missions using a Service Module bay loaded with scientific equipment. When it became obvious that later flights were being cancelled, such mission plans were brought into the J missions that were actually flown.

UNMANNED MISSIONS

Preparations for the Apollo program began long before the manned Apollo missions were flown.

Test flights of the Saturn I booster began in October 1961 and lasted until September 1964.

Three further Saturn I launches carried boilerplate models of the Apollo command/service module.

Two pad abort tests of the launch escape system took place in 1963 and 1965 at the White Sands Missile Range.

The only unmanned missions to officially include Apollo as part of their name rather than serial number were Apollo 4, Apollo 5 and Apollo 6. There were never Apollo 2 nor 3 flights.

Apollo 4 was the first test flight of the Saturn V booster. Launched on November 9, 1967, Apollo 4 exemplified George Mueller's strategy of "all up" testing. Rather than being tested stage by stage, as most rockets were, the Saturn V would be flown for the first time as one unit. The mission was a highly successful one. Walter Cronkite covered the launch from a broadcast booth about 4 miles (6 km) from the launch site. The extreme noise and vibrations from the launch nearly shook the broadcast booth apart- ceiling tiles fell and windows shook. At one point, Cronkite was forced to dampen the booth's plate glass window to prevent it from shattering.

This launch showed that additional protective measures were necessary to protect structures in the immediate vicinity (unfortunately, including media rooms).

Future launches used a damping mechanism directly at the launchpad which proved effective in limiting the generated noise.

Apollo 6 was the last in the series of unmanned Apollo missions. It launched on April 4, 1968, and landed back on Earth almost ten hours later at 21:57:21 UTC.

The following image shows the actual and desired Lunar Landing sites:

Lunar Landing Sites

Now, on to the missions themselves!