Retrieving the lander

LEAVING EARTH

In the years that have elapsed since the Apollo programme, people have forgotten the scale of what the S-IVB was designed to achieve. There is little appreciation of the difference between low Earth orbit and the reaches of space into which this rocket stage took the Apollo crews. In any case, many fail to understand the relative scale of the Earth-Moon system. I once gave a talk to schoolchildren about the Moon and used the popular method of scaling the solar system down to what our minds can handle. As props, along with a model of the Saturn V launch vehicle and some good photographs, I took my own model of the Earth-Moon system. Earth was represented by a 20-centimetre globe that I had been given some years earlier. The Moon was represented by a lucky find I made during a visit to the holy grail of aerospace memorabilia: the National Air and Space Museum in Washington, DC, in the USA. While browsing the museum’s gift shop, I had come across a 5-centimetre – diameter foam ball, grey and pockmarked with craters, that perfectly matched the scale of my globe of Earth, as the Moon’s diameter is very nearly one-quarter that of Earth.

During the talk, I threw my foam Moon out among the schoolchildren and asked the boy who caught it to come forward and hold the Moon beside my Earth at what he thought would be its correct distance. Repeated attempts by various children suggested distances between a half and one metre. Of course, I had previously calculated the correct distance and cut a piece of string to length, which I had rolled up around a pencil. I asked the final child to place the foam Moon at the end of the string and walk back until I had fed out its full length. Back she went up the aisle between the rows of seated children towards their teacher who’s eyes widened in amazement as the schoolgirl took my Moon all the way up to where she was seated. On the scale of my little model, the mean distance between Earth and the Moon was represented by a piece of string six metres long. I then explained how every flight into space by humans since the end of the Apollo programme had risen above Earth between 300 and 600 kilometres, no more than the thickness of that girl’s little finger.

W. D. Woods, How Apollo Flew to the Moon, Springer Praxis Books,

DOI 10.1007/978-1-4419-7179-1 5. © Springer Science+Business Media. LLC 2011

It was by virtue of the power of the S-IVB that Apollo transcended any space exploration before or since, and took men into the realms of deep space.

Astronaut Michael Collins understood the significance of the ТІЛ burn very well and wrote about it in his autobiography, Carrying the Fire. He was at the Capcom console in the mission operations control room (MOCR) in Houston, usually called simply mission control, and acted as the intermediary between the crew of Apollo 8 and the huge team of people occupying the building with him. He realised that TLI was what made this first manned flight to the Moon different from all the flights that had preceded it, and from any journey ever made by humans. On his own flight, Apollo 11, he yearned for a deeper appreciation of what TLI really meant.

“The umbilical snipping ceremony carries about as much drama as asking for a second lump of sugar. ‘Apollo 11, this is Houston. You are Go for TLI.’ I answer, ‘Apollo 11. Thank you.’ There should be more to it.”

Only 30 minutes after the completion of the TLI burn, the stack was already approaching an altitude equivalent to Earth’s radius. The home planet no longer filled half the sky as it had when their spacecraft hugged the world in its parking orbit. Now the crew could see the planet as a globe and view entire continents in a single glance. “You could see all of the United States. If the pictures come out, there will really be some pictures.” This was praise indeed from the laconic John Young during the debriefing for Apollo 16. His CMP Ken Mattingly concurred. “The Earth was right there in the window. And centred right in the middle of the Earth was the United States, without a cloud over it.’’

‘’All the way from the Great Lakes to Brownsville." added Charlie Duke.

"Just as if you had drawn it and set it up so you could take a picture of it.” continued Mattingly.

Young then changed the subject. "Why don’t you talk about TD&E. Ken’.’”

Young w’as referring to transposition, docking and extraction. a typically NASA – ese piece of nomenclature that concerned their next task. The CSM would separate from the S-IVB. coast a short distance away, turn, come back, dock with the LM and then pull it aw-ay from the nearly spent stage. By Apollo 16, Mattingly was familiar with this series of tasks. "That’s got to be the simplest manoeuvre performed in space flight," he said afterwards. “Thai was exactly like the simulator.”

During the Gemini programme. NASA had learned how to safely dock two spacecraft together, in the knowledge that such a capability would be an important part of future operations in space. Once the Saturn launch vehicle had set an Apollo mission on course for ihc Moon, the crew put the techniques learned to good use and docking became a means to an end rather than an end in itself.

Within the stack of the Apollo/Saturn space vehicle, the lunar module sat below the command and service modules, hidden away in a conical shroud known as the SLA (pronounced ’slaw’) which took the vehicle’s diameter from the 6.6-metre-wide S-I VB to that of the 3.9-meire service module. The initials SLA variously stood for spacecraft or service module to lunar module adapter or even spacecraft to launcher adapter, and it was the CMP’s task to retrieve the LM from its embrace in the final intensive task that had to be completed before the crew could settle down to the translunar coast. It did not always go according to plan.