SpaceX tested its next Falcon 9 rocket during a major countdown rehearsal Monday, loading propellant into the two-stage launcher and validating improvements made to the company's Cape Canaveral launch pad before liftoff as soon as Nov. 30.

The third Falcon 9 rocket sits on the launch pad. Credit: Kyle Cothern/SpaceX
 
The practice countdown, also known as a wet dress rehearsal, put the Falcon 9 rocket, the launch pad and control teams through drills to get ready for launch day.

The dress rehearsal included most countdown procedures before simulating an abort at T-minus 1 second.

The Falcon 9's first stage arrived at Cape Canaveral in April, followed by the launcher's second stage in July. Workers assembled the stages inside a hangar at Cape Canaveral's Complex 40 before rolling the booster out to the pad for Monday's countdown test.

SpaceX says engineers have upgraded the seaside launch pad since the Falcon 9's previous launch in December 2010, including adding new liquid oxygen pumps to reduce the fueling time from 90 minutes to less than 30 minutes. The improvement will streamline the Falcon 9 countdown for the next launch.

The mission's payload, the first full-up Dragon spacecraft, will be shipped to Cape Canaveral in early September, according to Kirstin Grantham, a company spokesperson.

The Dragon is currently undergoing final environmental testing and assembly at SpaceX headquarters in Hawthorne, Calif.

Workers prepare the Dragon spacecraft for thermal vacuum testing. Credit: Roger Gilbertson/SpaceX
 
The 15-story Falcon 9 rocket is due to blast off Nov. 30 with the Dragon cargo capsule bound for the International Space Station. It will be the first launch to the complex in NASA's partnership with the commercial space industry to develop and test private spacecraft to deliver supplies to the million-pound laboratory.

The upcoming flight will be the first Dragon with an operational service module, including a full complement of engines, extra fuel tanks and solar panels to generate electricity. The December test flight, which lasted about three hours, operated entirely on battery power and didn't need as much propellant as a mission to the space station.

For the last flight, the unpressurized trunk stayed attached to the Falcon 9's second stage in orbit. Only the retrievable Dragon capsule separted from the rocket.

The Falcon 9 rocket's inaugural launch in June 2010 was topped with a dummy Dragon capsule.

NASA tentatively approved SpaceX's request to combine the second and third in a series of three test flights of its Dragon spacecraft after a near-perfect demonstration mission in December. The space agency is withholding final judgment until engineers finish software testing and reviews of SpaceX's plans to launch two small commercial Orbcomm communications satellites on the same flight.

The rotation actuator of one of the Dragon spacecraft's solar array wings is tested on the ceiling of SpaceX headquarters in California. Credit: SpaceX
 
"Our team continues to work closely with NASA to resolve all questions and concerns," SpaceX said in an update posted on the company's website.

NASA is investing federal money into SpaceX and Orbital Sciences Corp. to develop spaceships to ferry supplies to the space station after the retirement of the space shuttle. Orbital Sciences plans the first test launch of its new Taurus 2 rocket in December, followed by flights to the space station in 2012.

If NASA permits SpaceX to launch Nov. 30, the Dragon capsule would reach the space station around Dec. 9. Once the capsule reaches a hold point just below the outpost, the lab's Canadian-built robot arm will reach out and grapple the cargo freighter, then transfer Dragon to a docking port.

It would stay at the space station for a few weeks, deliver some non-essential cargo in its pressurized cabin, then return to Earth via a splashdown in the Pacific Ocean.