Orion is designed eventually to take humans beyond the space station, to destinations such as the Moon and Mars. The flight today will be used to test critical technologies, like its heat shield and parachutes.
The Delta IV-Heavy rocket launched from Cape Canaveral at 07:05 local time (12:05 GMT). Orion will reach a peak altitude of 3,600 miles, fifteen times higher than the orbit of the International Space Station. That will mark the highest altitude any spaceship capable of transporting humans has reached since Apollo 17.
This will generate temperatures in the region of 2,000C, allowing engineers to check that Orion's thermal protection systems meet their specifications.
The mission teams will also get to watch how the parachutes deploy as they gently lower the capsule into Pacific waters off the coast of Mexico's Baja Peninsula. The splashdown is expected to occur at about 11:30 EST (16:30 GMT).