A Space Exploration Technologies' passenger spaceship made a quick debut test flight on Wednesday, shooting itself off a Florida launch pad to demonstrate a key emergency escape system.

​The six-metre (20 foot) tall Dragon capsule, a modified version of the spacecraft that flies cargo to the International Space Station, fired up its eight, side-mounted thruster engines at 9 a.m. ET/1300 GMT to catapult itself nearly 1.6 kilometres (a mile) up and over the Atlantic Ocean.

The flight ended less than two minutes later with the capsule's parachute splash-down about 2.6 km (1.4 miles) east of the Cape Canaveral Air Force Station launch site.

The purpose of the test was to demonstrate an escape system to carry the capsule to safety in case of a fire or accident during launch. SpaceX plans to refly the capsule later this year aboard a Falcon 9 rocket to test an abort maneuver at supersonic speed and high altitude.

"Essentially, it's kind of like an ejection seat in an airplane. You have the ability to leave the pad sitting in the capsule and the capsule would come off and land," NASA astronaut Eric Boe said during an interview on NASA TV.

"It's one of the things the (space) shuttle didn't have," added Boe, who twice flew as a space shuttle pilot.

NASA retired the shuttles in 2011 and invested in commercial companies' designs for a new generation of space taxis. The U.S. space agency currently is investing $6.8 billion US in privately owned SpaceX and Boeing.