Engineers troubleshoot helium, nitrogen leaks in shuttle rocket pod (UPDATED)

Editor's note...
  • Posted at 08:14 AM, 10/29/10: Engineers troubleshoot OMS pod helium, nitrogen leaks.
  • Updated at 09:20 AM, 10/29/10: Start of countdown delayed 24 hours; launch off until at least Tuesday.
By WILLIAM HARWOOD
CBS News

KENNEDY SPACE CENTER, Fla.--NASA managers decided early Friday to delay launch of the shuttle Discovery from Monday to at least Tuesday -- election day in the United States -- because of work to fix two leaks, one helium and one nitrogen, in the plumbing of the orbiter's right-side orbital maneuvering system rocket pod.

The start of Discovery's countdown will slip one day to 2 p.m. EDT (18:00 GMT) Saturday. Assuming the repair work goes smoothly, the shuttle could be ready for launch by Tuesday, at 4:17:56 p.m. (20:17:56 GMT), but that remains to be seen. The current launch window extends through Nov. 7.

"This is not a huge deal, but we just have no cushion in the schedule," a NASA official said earlier today.

Two interim problem reports, or IPRs, were written up overnight, one because of a gaseous nitrogen leak at a quick disconnect fitting and another in the helium pressurization system that is used to push propellants into the OMS pod engines.

The first problem showed up during a gaseous nitrogen fill valve leak check and the second issue was discovered after the helium system was pressurized for launch. An inspection revealed an internal O-ring in a ground-system helium coupling was partially stuck inside its shuttle counterpart. That fitting apparently will have to be replaced.

The right-side OMS pod was re-installed in July after work to fix a helium isolation valve that had problems during Discovery's most recent mission in April. A leak in a fuel crossfeed line associated with the right OMS pod was repaired last weekend when two internal seals were replaced.

NASA officials say the current leaks are not related to last weekend's repair work or the rocket pod's removal and reinstallation. This status report will be updated after a countdown status briefing at 10 a.m. EDT (14:00 GMT).