40 years after Apollo, engineers look back

As President Obama hailed three astronauts for expanding the human conception of what is possible, Eldon Hall, who worked on hardware for the Apollo program, opened a briefcase and displayed the nuts and bolts of celestial imagination. Inside were various antiquated elements from the development of the Apollo computer system - transistors, vacuum tubes, and circuit boards that looked like they belong in a museum.

It was a reminder that when Neil Armstrong took his small step into the powdery, alien landscape, a cadre of support teams on the ground - some right here in Cambridge - was making it possible.

Hall even ventured a playful crack at the astronauts’ expense. Computers of that era, he acknowledged, were hardly user-friendly, requiring punch cards to interact. But the men with the right stuff were not especially computer-friendly. “We had to punch the astronauts to get them to talk to the computer,’’ he said. “There was mutual distrust.’’

The astronauts were the public face of the space program, and it is the images of them lumbering across the lunar landscape that have long entranced the public. But their journey would not have been possible without the scientists and engineers toiling behind the scenes, and more than 100 came together yesterday at Draper Laboratory, recalling the extreme deadlines of the space program and some of the luck, anxiety, and risks that were part of the race to get a person on the moon.

Draper developed the guidance, navigation, and control systems that allowed the astronauts to land on the moon and return to Earth. Scientists there worked on the flight computer and provided essential support during the missions, in a job that many said yesterday was the highlight of their careers.

“The heart stopped beating’’ when the astronauts finally touched down, said Lance Drane, now 66. Of course, Drane never stepped foot on the moon but, over and over again, he ran digital simulations while working at the Draper Laboratory four decades ago.

Given the endless stream of memoirs and documentaries, Norm Sears, who played a leading role in developing the guidance system for the Apollo missions, decided that the only way to tell an original story was to focus on the part he knew best - the “subsystems level.’’ That included attempts to make sure the lunar landing module, or “bug,’’ was as light as possible because each pound dramatically increased the need for fuel.

Peter Vernham said that in his job, doing in-flight and post-flight analysis, space flight’s more primitive side becomes clear.

The best way to get the data that he would analyze was to take dictation. So Vernham and one other person would both write down a string of numbers, compare notes to make sure both sets matched, and then put the information on a punch card for input into a computer.

Others recalled highs and lows that came independent of their technical involvement.

Jerold Gilmore, 75, who is now a consultant at Draper, said he was on duty during Apollo 8. The astronauts read aloud from Genesis. It was exhilarating, he said.

John Miller, who worked on hardware for the Apollo program, described the thrill of watching a launch, even from 5 miles away. He described the light, the smoke, and a penetrating low-frequency sound “strong enough to make your stomach rumble.’’

Bruce McCoy, 69, who traveled from San Diego for the reunion, said that during Apollo 11, he was in Houston, giving support to the flight directors. When questions came up about the guidance systems, he said, he would give them answers, because at Draper he worked on developing the software for the lunar module. To make sure people would be alert and able to answer questions, McCoy and colleagues were on a strict shift schedule, and he missed the landing.

“All the excitement, and I slept through it,’’ McCoy said.

Carolyn Y. Johnson can be reached at cjohnson@globe.com.