Discovery's final flight


Kristen Dahlgren

CAPE CANAVERAL, Fla. (NBC) - Almost four months delayed and decades in the making, later today we could see the Space Shuttle Discovery's final flight.

It was poised to lift off last November, but after a weather, then hydrogen leak delay, technicians discovered potentially dangerous cracks in the external tank.

The Shuttle was rolled off the launch pad for unprecedented repairs.

Shuttle Commander Steve Lindsey said, "This is probably one of most difficult technical challenges we have faced in recent years."

But after all of the trials, Shuttle Launch Director Mike Leinbach said, "Discovery looks like she'll fly this time."

When it does lift off, Discovery will carry more than a closet full of supplies and a humanoid robot to the International Space Station. There is also history on board.

Discovery once carried the first female pilot, the first African American spacewalker, and the oldest astronaut, John Glenn.

It returned Americans to space after the Challenger and Columbia disasters.

"It is the end of a 30 year program that not only have we worked in and made our livelihoods in, but we've grown to love," said Leinbach.

So for many, its last liftoff will be bittersweet, but after all Discovery has been through, they hope this time the final countdown goes off without a hitch.