Today, we ride on the world's largest land
transport vehicle. The University of Houston's
College of Engineering presents this series about
the machines that make our civilization run, and
the people whose ingenuity created them.
What do you suppose the
largest land transport vehicle is? A bus, a train,
an earth-mover? Actually, its the crawler
transporter developed for NASA to carry an
assembled Saturn rocket on its five-mile journey
from the assembly building to the launching pad.
This strange vehicle makes more sense as an
engineering accomplishment when we realize the
magnitude of its task. It had to carry a
12-million-pound rocket and launching derrick, and
it had to keep them within ten minutes of an arc of
a pure vertical position while it negotiated grades
of as much as five degrees.
The crawler transporter was selected in preference
to both a special barge-and-canal system and a rail
system. What finally emerged was something out of
science fiction. It's 131 feet long and 114 feet
wide. It weighs 6 million pounds. The structure
rides on four double tracks -- each pair the size
of a Greyhound bus. Inside its huge deck are diesel
engines with a total output of almost 8000 hp. They
drive generators that supply electric motors for
the tracks, for the immensely-delicate leveling
mechanism, for the cooling systems, and for other
internal functions.
The five-mile journey requires a highly trained
crew of eleven people: a driver, four observers at
different locations to advise the driver on
steering, and six technicians. The crawler moves at
2 mph unloaded and 1 mph with the rocket in place.
Its fuel economy is about 1/150th of a mile per
gallon.
And who built this high-tech behemoth? Actually,
two were built, and they weren't products of the
aerospace industry. They were made by the Marion
Power Shovel Company of Ohio -- a company with
experience in heavy moving technology. The crawlers
each cost $14 million in 1967, when they were put
into service.
This is the sort of design challenge that gives
engineers enormous pleasure -- a new machine that
must conform to a set of extraordinary requirements
-- an array of decisions and component inventions
that molds dramatic function out of thin air.
I'm John Lienhard, at the University of Houston,
where we're interested in the way inventive minds
work.
(Theme music)
