During the launch countdown, Chandra finally tells the computer the truth.

Martha has been preparing the surviving humans to concentrate their thoughts on the Doctor upon the completion of the launch countdown.

The digital launch countdown was still going.

What are the procedures from end to end until the launch countdown?

Her finger rested on the manual releases as she watched the launch countdown.

You will lose another pay grade for every launch countdown hold attributable to you.

It's dangerous as hell to interrupt a launch countdown after the rocket fuel tanks have been pressurized.

Snake destroys the weapon before its launch countdown is completed.

The first, pushed by Joni, activates a launch countdown.

Once occupied a launch countdown begins and upon completion the rocket launches.