Transporters First Carried Apollo Rockets To The Pad

They were originally seen as something of a folly, with no less an authority than Walter Cronkite stating they might never work. That was over 40 years ago, however... and today, NASA's massive crawler transporters are expected to carry the future of manned spaceflight to the launchpad.

Crawler Transporters 1 and 2 -- known colloquially by NASA scientists as "Hans" and "Franz" -- are still hauling such vehicles as the space shuttle from hangars at Kennedy Space Center to the launchpad, and they show no signs of stopping.

"They can go another 100 years," said Robert Rokobauer, a systems engineer with United Space Alliance, to Florida Today. Rokobauer was one of several attendees at a  ceremony Friday honoring the engineers who made the transporters a reality.

The massive transporters were first suggested by NASA in the early 1960s, and were necessary to move the enormous Saturn rockets used by the Apollo program to the launchpad.

Constructed by the Marion Power Shovel Company, the transporters were nearly doomed by early problems with bearings in the crawlers' levelling systems that were necessary to keep payloads level as the transporters climbed the slight incline to the launch pads.

"These crawlers had some initial problems that seemed almost insurmountable to some people outside the space center," said retired NASA engineer Bill Clemens. "These were serious problems."

It was at this point that Cronkite weighed in, saying the transporters might never work.

NASA clearly needed to fix the problem, and the late Philip Koehring Sr., a Marion Power Shovel project manager, was tapped to lead a redesign.

In record time, Koehring developed a new hydraulically lubricated sleeve bearing made of a bronze alloy, and that solved the problem. The crawlers -- each taller than a two-story building, as wide as an eight-land highway, and powered by two 2,750 horsepower engines -- first carried NASA rockets to the launch pad in 1966.

Each transporter has logged 1,800 miles going back and forth between the Vehicle Assembly Building and KSC's two launch pads, carrying Saturn Vs and space shuttles at the blistering pace of 0.9 miles per hour with a full 12 million pound load.

And they'll continue to work in the future, carrying NASA's future CEV rockets to the launchpad on missions to the ISS -- and, possibly, Mars.

"They are impressive pieces of equipment," said Michael Wetmore, a launch integration manager for NASA.

"There were a lot of naysayers 40 years ago, but the proof is right here," said Koehring Sr.'s son, Philip Koehring Jr. "[The crawlers] are still working."

FMI: www.nasa.gov