NASA today will decide if it's safe to launch space shuttle Discovery next Friday on an International Space Station assembly mission. In a flight readiness review starting at 9 a.m., top managers and engineers will pour over data collected from weeks of testing on propulsion system valves that, if damaged, could put astronauts at risk as they rocket into orbit.
They'll determine if the risk is acceptable for at least one mission while tests continue.
"It will be dependent on where the data leads the teams, and whether everyone can get comfortable with a one-flight rationale," said NASA spokesman Kyle Herring.
Conclusions will be announced today at a news conference scheduled no earlier than 5 p.m. You can watch live here on The Flame Trench - click on the NASA TV image at right to launch a viewer.
Briefing participants include Bill Gerstenmaier, associate administrator for space operations; John Shannon, space shuttle program manager; and Mike Leinbach, space shuttle launch director.
The three flow control valves in question work like pop-up lawn sprinklers to route gaseous hydrogen from the shuttle's main engines through a line to the external tank's liquid hydrogen reservoir, maintaining its pressure as the fuel is consumed.
The lip of one valve broke off during Endeavour's launch in November, raising new concerns that failed valves could rupture the gaseous hydrogen line or over-pressurize the tank.
Those events could cause an explosion or early shutdown of the main engines.
Engineers at five NASA centers conducted impact tests and developed computer models to better understand worst-case scenarios and their probability.
Today's review resumes one that began Feb. 3, when Discovery was targeted to launch Feb. 12.
The decision was made then to put off the launch to continue testing the valves.
You can read more about the flow control valves and see pictures of them in this fact sheet.
During a planned two-week mission, Discovery's seven astronauts will install the last piece of the space station's central backbone and deploy a final set of American solar array wings.
IMAGE NOTE: On Jan. 14, space shuttle Discovery rests on launch pad 39A after a seven-hour rollout from the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida. At left are the fixed service structure (next to the shuttle) and the rotating service structure. Discovery is targeted to launch to the International Space Station on a 14-day mission to install the S6 truss segment and its solar arrays to the starboard side of the station, completing the station's backbone, or truss. Photo credit: NASA/Troy Cryder
No comments:
Post a Comment