Thrust Oscillation concerns worsen
Last month, Sentinel Space Editor Robert Block reported on the likelihood that the first test flight of the Ares I-X -- a mockup of the Ares I intended ot test performance of the solid-fuel first stage -- would be delayed past its scheduled date of Aug. 30. Officially, he reported, NASA was holding to the August date for liftoff at Kennedy Space Center but that September was "more likely."
Now comes the officially revised date, courtesy of a memo from Johnson Space Center's Robert Ess, the Ares I-X mission manager: Oct. 31.
"This is still a very aggressive schedule and requires a lot of tasks to complete on or before their planned dates," Ess wrote in a memo obtained by the Orlando Sentinel.
And there's word from Marshall Space Flight Center, where Ares I is being designed, that engineers there are continuing to wrestle with the issue of "thrust oscillation." A blog post by Dan Kanigan, a public information officer at Marshall, explains the problem this way:
"The vibration that is produced by the burning of the solid rocket propellant in the first stage booster is called thrust oscillation. These vibrations -- or oscillations -- come in the form of waves, which travel up and down the length of the rocket like a musical note through an organ pipe. One of the biggest challenges in any rocket design is developing avionics (aviation electronics) that can function in this vibrating environment."
Kanigan confirms that the Air Force's 45th Space Wing’s Range Safety team remains concerned, As Block also reported, that thrust oscillation will vibrate Ares I so badly that it will disable both the Thrust Vector Control system that steers the rocket and the Flight Termination System that would be used to blow it up if the rocket veered of course.
Read The Write Stuff posting HERE.