Laser-powered elevator to space hits some snags

A laser-powered robot failed to complete its climb up a long cable dangling from a helicopter Wednesday in a $2 million competition to test the potential reality of the science fiction concept of space elevators.

The highly technical contest brought teams from Missouri, Alaska and Seattle to Rogers Dry Lake in the Mojave Desert, most familiar to the public as a space shuttle landing site.

The contest requires their machines to climb 2,953 feet (nearly 1 kilometer) up a cable slung beneath a helicopter hovering nearly a mile high.

The Kansas City, Mo., Space Pirates team was first off the ground after hours of testing the cable system, refueling the helicopter and waiting to fire up the laser so it doesn't interfere with satellites.

Its climber, a flat machine several feet square, initially failed to respond to laser power and was lowered, examined and sent back up. On the second try it began moving and then stopped.

On the third try it began moving steadily, but then trouble developed as the laser could not stay locked on the machine. It failed to climb all the way up before the laser had to be shut off to protect satellites, said Ted Semons of the sponsoring Spaceward Foundation. The team was expected to try again Friday.

Funded by a NASA program to explore bold technology, the contest is intended to encourage development of a theory that originated in the 1960s and was popularized by Arthur C. Clarke's 1979 novel "The Fountains of Paradise."

Space elevators are envisioned as a way to reach space without the risk and expense of rockets.

Instead, electrically powered vehicles would run up and down a cable anchored to a ground structure and extending thousands of miles up to a mass in geosynchronous orbit - the kind of orbit communications satellites are placed in to stay over a fixed spot on the Earth.

Electricity would be supplied through a concept known as "power beaming," ground-based lasers pointing up to photo voltaic cells on the bottom of the climbing vehicle - something like an upside-down solar power system.

The space elevator competition has not produced a winner in its previous three years, but has become increasingly difficult.

Semons said the competing machines all use wheels to grip the cable. Two use modified inline-skate wheels and one uses steel wheels.

The vehicles must climb at an average speed of 16.4 feet (5 meters) per second, or about 11 miles (18 kilometers) per hour, to qualify for the top prize. A lesser prize is available for vehicles that climb at 2 meters per second.

The rules allow one team to collect all $2 million or for sums to be shared among all three teams depending on their achievements.

The other teams scheduled to compete later Wednesday were the University of Saskatchewan Space Design Team, known as USST, and LaserMotive of Seattle.

The teams were scheduled to make attempts Wednesday and Thursday. Additional attempts were possible Friday, Semons said.