At 2:25 pm EST SpaceX announced that a structural issue in the first stage fuel tank of the Falcon 1 launch vehicle had arisen and that the launch is off until at least next month.

The customers for this first mission are DARPA and the U.S. Air Force.  The payload is FalconSat-2, part of the U.S. Air Force Academy’s satellite program that will measure space plasma phenomena, which can adversely affect space-based communications, including GPS and other civil and military communications.

The target orbit for this satellite is 400 km X 500 km at an inclination of 39 degrees.

SpaceX Update Posted December 19, 2005 at 4:40 p.m. California time: Here is the apparent cause of structural damage (further analysis may change the conclusion):

Due to high winds, we placed the countdown on hold and began draining the fuel tank.  As we drained fuel from the 1st stage tank, a faulty pressurization valve caused a vacuum condition in the tank.  This caused a fuel tank barrel section to deform and suck inward.  It is important to note that the root cause is an electrical fault with a valve, not structural design. 

 At this point, it appears that no other damage was sustained to the vehicle or the satellite.  The rocket will be lowered down this afternoon and placed in its hangar for further inspection.

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