After testing sensors and engines, the craft will conduct two major engine firings to take it to the space station's altitude.

The tests will be attempted instead during the final countdown for the engine firing.

Between 20 and 50 test flights of Lynx are planned, along with numerous static engine firings on the ground.

During engine firing, thrust loads force the exit cone liner against the case.

Then the crews must turn around and begin a 72-hour operation leading up to the engine firing Monday.

They had come earlier this time, before main engine firing.

A series of engine firings over the next two days guided the ship to set up a rendezvous with the Space Station.

The crew performed six successful engine firings to set up the on-time docking.

Another engine firing, also scrutinized by the satellite, served as a brake.

They heard the rough roar of a motorcycle's engine firing.