SpaceX Examines Cracked Engine Nozzle on Private Rocket
The private spaceflight company SpaceX test fires the nine engines of its second Falcon 9 rocket on Dec. 4, 2010 at Cape Canaveral Air Force Station in Florida ahead of a planned Dec. 7 launch to test the company's new Dragon space capsule. Credit: SpaceX
Credit: SpaceX

CAPE CANAVERAL, Fla. ? The private spaceflight company SpaceX is examining a cracked engine nozzle on its commercial Falcon 9 rocket that has ?delayed the inaugural launch of the firm's new Dragon space capsule.

The company, formally known as Space Exploration Technologies, planned to launch the Falcon 9 rocket and its first operational Dragon space capsule today (Dec. 7). But the company postponed the launch after discovered two cracks in the aft end of the second-stage engine nozzle extension of the Falcon 9 rocket.

NASA and SpaceX officials have stated that a launch attempt could occur as early as Wednesday. SpaceX is expected to announce a decision this evening.

The two cracks are located in a region near the end of the nozzle extension. Since the area experiences little stress, the fractures would likely not have caused a flight failure on their own, SpaceX officials said. [INFOGRAPHIC: Inside Look at SpaceX's Dragon Capsule]

The bell-shaped nozzle extension, which measures 9 feet (2.7 meters) tall and 8 feet (2.4 m) in base diameter, is made of an alloy metal with a melting temperature high enough to boil steel. Yet, despite its intricacies, this component is geometrically the simplest part of the engine, SpaceX officials said.

The Dragon spacecraft and Falcon 9 rocket form the core of SpaceX's plan to provide unmanned cargo deliveries to the International Space Station under a $1.6 billion contract with NASA. SpaceX will provide 12 Dragon flights under that contract.

NASA plans to rely heavily on commercial spacecraft such as SpaceX's Dragon for access to low-Earth orbit once the agency retires its space shuttle fleet next year.

SpaceX founder Elon Musk, a millionaire who also co-founded the Internet payment service PayPal, has said that while the initial Dragon capsules will serve as unmanned space freighters, SpaceX is also developing a crewed version of the spacecraft to carry up to seven people on round trip flights to orbit. ?

For the Dragon capsule's maiden flight, engineers and technicians are completing a thorough investigation to ensure that these cracks are not symptomatic of more serious problems.

SpaceX initially stated that a new launch attempt would not occur earlier than Thursday, with additional opportunities on Friday and Saturday if needed.?

The company is considering several options, including repairing the crack or shipping a replacement part from their headquarters in Hawthorne, Calif.

"The most likely path forward is that we will trim off the thinnest portion of the nozzle extension, which is where the cracks are located, perform a thorough systems check and resume launch preparation," SpaceX officials said in a statement.

SpaceX's Falcon 9 rocket set to launch this week is the second Falcon 9 booster to fly. The company successfully launched its first Falcon 9 rocket in June.

You can follow Staff Writer Denise Chow on Twitter @denisechow.