Skip to comments.Space Station Maneuvering System Fails
Posted on 10/12/2006 7:05:01 AM PDT by Fitzcarraldo
Trouble on the International Space Station could mean changes for the next space shuttle mission.
Astronauts aboard Discovery could find themselves on a repair mission, WESH 2 News reported.
That's because part of the space station's maneuvering system is not working. Mission Controllers shut down one of the station's four stabilizers. They keep the station correctly oriented in space.
So on Discovery's scheduled December mission, astronauts may have to toss out their assembly plans and make repairs instead.
Station gyro off line; impact on shuttle flight assessed
BY WILLIAM HARWOOD
Posted: October 11, 2006
One of the international space station's four control moment gyroscopes, used to keep the outpost properly oriented without jarring, fuel-consuming rocket firings, was taken off line late Monday because of concern about repeated instances of excessive vibration.
While CMG-3 has not been officially declared failed, flight planners are scrambling to assess the potential impact of a failure on the shuttle Discovery's upcoming mission in December to rewire the space station to take advantage of newly delivered solar arrays.
During the third of three planned spacewalks during Discovery's flight, CMGs 1 and 4 will have to be shut down while spacewalking astronauts unplug and replug electrical cables routing solar panel power to two of four main electrical circuits.
If CMG-3 is not available to help control the station's orientation, rocket thrusters might have to be used to augment CMG-2.
But the newly installed P4 solar array panels, which stretch 240 feet from tip to tip, are designed to rotate to track the sun as the station circles the globe. It's not yet clear whether the fragile masts that support the extended arrays can withstand jarring rocket firings while rotating. And they need to rotate to generate the necessary power.
Depending on the results of an engineering assessment, CMG-3 could be put back on line full time, brought up for specific events like the spacewalk in question or left off line but available for use as an emergency backup. Engineers also are assessing whether the arrays can simply be locked in a power-favorable position, if necessary, during the spacewalk.
The station's four control moment gyroscopes maintain the lab's orientation in space without having to tap into limited supplies of on-board rocket fuel. They are housed in the Z1 truss, which was attached to the Unity module's upward-facing, or zenith, hatch during shuttle mission STS-92 in October 2000.
Along with saving fuel, the 800-pound gyros, spinning at 6,600 rpm, allow station crews and flight controllers to reorient the outpost and keep it stable without using rocket firings that would jar sensitive microgravity experiments. Or the new P4 solar arrays, installed during the shuttle Atlantis's mission in September.
The station's orientation can be maintained with just two CMGs in a worst-case scenario. On June 8, 2002, CMG-1 suffered a malfunction and shut down. Station astronaut Carl Walz reported hearing an unusual noise inside the Unity module. He said the noise appeared to be coming from the module's zenith area. Mission control then told Walz engineers were working an issue with a spin bearing in CMG No. 1. Walz said the noise was quite noticeable inside the module.
"We're hearing a pretty loud, audible noise, kind of a growling noise, from inside the node," Walz reported. "It looks like we have a mechanical failure of the spin bearings on CMG-1," an astronaut in mission control replied. "It's currently spinning down right now. The growling noise is undoubtedly due to vibration."
That CMG was replaced with a spare during the first post-Columbia shuttle mission in 2005. No other backups are available, but the failed gyro currently is being refurbished. Depending on what happens with CMG-3, the refurbished gyro could be added to an upcoming mission.
"Moderator: this is definitely breaking news."
No, it's news about a break.
The ISS is ill conceived, and less than functional. Get the people off and enjoy the light show as it re-enters the atmosphere.
"But, we've spent billions - we must go on!"
Can the station and the crew on it wait 'til December?
"But, we've spent billions - we must go on!"
That's what's known as throwing good money after bad.
I support the space program. But the ISS is a b*st*rd child. Too many cooks.
There was no hesitation cutting off three missions (costing approx. $4 billion in 1972 dollars) from a highly successful project called Apollo.
*sigh* Therein lies the rub. Once a behemoth like that starts rolling, its momentum alone assures years of continued waste before it can safely be brought to a halt.
Let's skip the Lunar base and go for Mars.
A lunar base would become yet another underfunded struggle for existence, like the space station and shuttle.
Have they tried some duct tape?
NASA- Duct Tape Suggested for Spacewalk Repair
AP ^ | 7/11/06
Today: July 11, 2006 at 7:26:19 PDT
Duct Tape Suggested for Spacewalk Repair
By MIKE SCHNEIDER
CAPE CANAVERAL, Fla. (AP) -
Even in space, a little duct tape may work wonders. Astronaut Piers Sellers suggested using some of the multipurpose sticky material to fix a safety-jet backpack used during spacewalks after it almost came loose from him while he repaired the international space station.
We've got to relearn how to crawl before we can walk. I'm all for the mission to Mars, but it is several orders of magnitude more complicated than the mission to Luna.
NASA was ready to send people to Mars in 1986 - for that matter von Braun had a plan to do it in 1952.
Let's stay home...
I think they need the duct tape to tape up the NASA admin and his staff.
Let's send them to Mars with the minimum needed to live off the land there. If it requires advanced technoogy, like nanotech, let's develop it - it will be useful in the private sector.
And if it hits the Taco Bell sign, we all get a free taco, so something good may yet come out of the program.
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