Hours After Shuttle Launch, Vital Radar Test Hits Snag

One of the prime experiments on the shuttle Endeavour’s Earth-monitoring mission ran into trouble Saturday just hours after the craft’s dawn liftoff.

A high-power amplifier for one of two radar instruments aboard Endeavour wouldn’t work, and researchers had to pass up viewing opportunities. Ground controllers spent several hours struggling with the problem before activating the amplifier in a manual mode. The amplifier is vital because it powers the radar’s antenna.

Mission Control told the crew that the flight would be extended from nine to 10 days, thanks to their efforts at power conservation.

Engineers continued to study the amplifier trouble and late Saturday night, after numerous tests, began scanning Earth with the radar.

While that radar was down, the other radar took its first images as Endeavour flew over Michigan’s Upper Peninsula.

The equipment is supposed to be the most advanced space radar ever built for civilian use. The mission is meant to provide the most extensive monitoring of Earth’s environment ever made from orbit.

The main purpose of the mission is to see how well the radar works. Scientists will compare the radar images of Earth to thousands of photographs to be taken by the six astronauts and the results of on-the-spot surveys by research teams.

After two launch delays last week, the 4.5-million-pound shuttle thundered from its seaside pad right on time at 4:05 a.m. PDT.