NASA Still Looking at Monday Shuttle Launch

Engineers are still trying to repair the space shuttle Endeavour said they remain hopeful the problem can be resolved in time for the shuttle to launch Monday.

After getting access to Endeavour's engine compartment Saturday after the removal of rocket fuel from the shuttle's tank, technicians narrowed down the problem to two potential causes. They said one of those causes is easy to fix, the other is difficult.

Technicians reported that the problem could be traced to a thermostat, a part that could be replaced in a few hours.

However, the problem could also be related to a controller that routes power to heaters in an auxiliary power unit. In that case, the launch would be delayed until at least May 8 because of the complicated process required to repair or replace the controller.

Further troubleshooting should isolate the cause to one of the two possibilities, managers said.
Mission managers will discuss the options Sunday morning and decide on a launch date. A launch on Monday would be at 2:33 p.m. ET.

Endeavour's launch was called off Friday when heaters in an auxiliary power unit failed. The power units control the shuttle's steering systems during launch and landing.  Many dignitaries including President Obama and the First Family were going to attend last Friday's launch.