This story originally appeared on CNET.com

(CNET) KENNEDY SPACE CENTER, Fla. - Three days after a last-second launch abort, an unmanned cargo ship designed and built as a private venture blasted off early Tuesday and streaked into orbit, kicking off a complex test flight to pave the way for commercial resupply missions to the International Space Station.

With a replacement valve installed in the engine that derailed a launch try Saturday, all nine of the booster's first stage powerplants roared to life on time at 3:44:38 a.m. EDT, throttling up to full thrust with a rush of fiery exhaust.

An instant later, after lightning-fast computer checks to verify the performance of the SpaceX-designed Merlin engines, the rocket was released from its firing stand and quickly climbed away from launch complex 41 at the Cape Canaveral Air Force Station.

To reach the International Space Station, the Falcon 9 and the solar-powered Dragon cargo ship had to take off at roughly the moment Earth's rotation carried the launch pad into the plane of the space station's orbit. Any hiccups in the countdown would have triggered another frustrating three-day launch delay for a flight already running months behind schedule.

But as it turned out, the company did not need an extended window. There were no technical problems of any significance the second time around, the weather cooperated and a few minutes after the space station passed over the launch site, the 157-foot-tall rocket took off on a northeasterly trajectory and set off after its quarry.

"Every bit of adrenalin in my body released at that point," said SpaceX founder Elon Musk. "It's obviously an extremely intense moment. The main thing I was wondering was would we have a valve-related issue on launch, would the first stage perform nominally? But it worked perfectly. I was really glad to see that."

The first stage engines burned for three minutes, shutting down in sequence as their propellants were exhausted. The first stage then fell away and the single Merlin engine powering the rocket's second stage ignited to continue the push to orbit.

Live video from cameras mounted on the Falcon 9 showed the launch site falling away from the rapidly accelerating rocket and later, the nozzle of the second stage engine, glowing red with the heat of combustion.

The second stage engine shut down as planned 9 minutes and 14 seconds after liftoff. About 35 seconds later, the Dragon capsule separated from the second stage, visible in a forward-pointing camera as it floated away into space.

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SpaceX cargo ship blasts off to International Space Station in NASA's first commercial flight