NASA Considers Shuttle Launch "As Is"
Sensor Malfunction Cause Still Unknown; Earliest Next Launch Would Be Saturday
-
-
Photo
Space shuttle Atlantis launch director Doug Lyons seems surprised to hear Mission Management Team chairman Leroy Cain say the shuttle might launch "as is," during a news conference Thursday, Dec. 5, 2007. (Nicholas Kamm/AFP/Getty)
-
Photo
Space shuttle Atlantis sits on the launch pad after the scrub, Thursday, Dec. 5, 2007. (Stan Honda/AFP/Getty)
-
Photo
Space Shuttle Atlantis, partially obscured behind the rotating service structure, sits on launch pad 39-A at the Kennedy Space Center in Cape Canaveral, Fla., early on the morning of Dec. 6, 2007. (Matt Stroshanen/Getty)
-
Photo
The official crew portrait of the Space Shuttle Atlantis: From the left (front row) are Stephen N. Frick, commander; Leopold Eyharts, European Space Agency; and Alan G. Poindexter, pilot. From the left (back row) are mission specialists Leland D. Melvin, Rex J. Walheim, Stanley G. Love and Hans Schlegel of the ESA. (AP/NASA)
-
-
Interactive
Eye On Space
Explore the mysteries of our solar system, galaxy and universe, and track the struggles and triumphs of human space exploration.
-
Photo Essay
Atlantis Mission STS-122
Space shuttle brought Europe's Columbus lab to the international space station.
That problem forced a delay of the space shuttle's launch on a space station assembly mission until Saturday at the earliest.
If those sensors fail to detect when the external fuel tank is empty, the engines could continue to run dry, and explode.
Based on electrical data seen during fueling Thursday, engineers believe the problem involves an open circuit in the wiring between an electronic box in the shuttle's engine compartment and the sensors at the base of the hydrogen section of the external tank. Given the shuttle's short eight-day launch window, NASA managers Thursday ruled out opening up the engine compartment to attempt any inspections of repairs.
LeRoy Cain, chairman of NASA'S Mission Management Team at the Kennedy Space Center, told reporters late Thursday engineers will meet again Friday to reconsider their options, adding they may not get comfortable with a fly-as-is rationale in time for a Saturday launch.
In the meantime, NASA managers ruled out a fueling test Friday and decided instead to top off the shuttle's onboard supply of liquid hydrogen to power the ship's electricity producing fuel cells. That would permit launch attempts Saturday and Sunday and still provide enough on-board supplies for a two-day mission extension and the addition of a fourth spacewalk.
Three spacewalks are required to connect the European Columbus research lab to the station; to replace a nitrogen coolant system pressurization tank; to install a pair of experiments on the Columbus module; and to move a failed space station gyroscope to the shuttle for return to Earth.
NASA managers want to add a fourth spacewalk if possible to permit a detailed inspection of a stalled solar array rotary joint to help engineers figure out what sort of repairs might be needed to get the joint turning smoothly again. But an additional spacewalk would require a two-day mission extension and that, in turn, is based on how much hydrogen and oxygen is available to power the ship's fuel cells.
We'll try to put together an operational workaround plan that we can get comfortable with that will allow us to go fly on Saturday.
LeRoy Cain, NASAAtlantis' launch window closes Dec. 13 because of power and temperature issues related to the space station's orbit. The window reopens Dec. 30, but senior NASA managers have said launch would be delayed to at least Jan. 2 if the shuttle team misses the current window.
NASA managers had high hopes for a launching Thursday, with a forecast calling for a 90 percent chance of good weather and no technical problems of any significance at pad 39A. After a short 13-minute Mission Management Team meeting, engineers were cleared to begin loading a half-million gallons of super cold liquid oxygen and hydrogen rocket fuel into Atlantis' external tank at 7:06 a.m. A few minutes later, the engine cutoff - ECO - sensors at the base of the tank were covered with supercold propellant.
The ECO sensors are part of a backup system that ensures the shuttle's three main engines don't drain the tank in the event of other problems during the climb to space that might prevent an on-time shutdown.
The ECO sensors can indicate two possible states: wet or dry. If the sensors falsely indicated they are submerged in fuel when, in fact, the tank is dry, the engines could run out of propellant while operating at flight pressures, speeds and temperatures, suffering catastrophic failures.
Based on the logic used in the computer software that monitors the sensors during ascent, two "failed wet" sensors would have no impact. But a third sensor failing wet could trigger a premature engine shutdown to protect against the possibility of the remaining sensor failing in the dry state. Launching with two sensors in the failed wet state would leave no redundancy in the system.
Propellants flow into the tank from the bottom and shortly after the four engine cutoff sensors at the base of the hydrogen section were submerged Thursday, commands were sent to simulate dry conditions to make sure the circuitry responded properly. Voltage readings from two of the sensors immediately indicated a dry state while sensors 3 and 4 showed voltages higher than 13.5 volts, an indication of an open circuit. The readings occurred simultaneously.
"What's currently in the plan is that we'll try to put together an operational workaround plan that we can get comfortable with that will allow us to go fly on Saturday," Cain said. "And it would be with the intent of flying with one or more failures potentially in the system when we go tank up again."
A premature engine shutdown could result in a trans-Atlantic landing. An emergency landing in Spain or France would cause major disruption to the space station assembly schedule and NASA's plans to complete the outpost and retire the shuttle by 2010.
Engineers say the odds of a premature engine shutdown in this case are acceptably remote because multiple failures would be required - ECO sensor failures as well as a leak or problems elsewhere in the system that would cause the shuttle to use up its hydrogen fuel at a higher-than-expected rate.
But not everyone agrees. Some engineers favor rolling Atlantis back to the Vehicle Assembly Building for repairs. NASA Administrator Mike Griffin participated in Thursday's Mission Management Team meeting and presumably will weigh in on how the agency proceeds this weekend.
© MMVII, CBS Interactive Inc. All Rights Reserved.



I sure wouldn''t want to be an astronaut on this mission!
In fact, each NASA shuttle is *still* at risk from the same launchtime debris impacts that killed Columbia. The difference in mission outcomes, if any, remains one of sheer (blind) luck.
NASA resumed launches after literal years of wrestling (unsuccessfully) with the icing and foam debris problems. Announcing its new shuttle launch schedule for July 4, 2006, NASA said the agency had done all it could be expected to do (?) with the ice hazard, and now, it would return to business as usual.
A second of the NASA safety corrections ordered by the post-Columbia inquiry was to develop effective means of patching in-flight damage to the carbon-on-carbon leading edge (not the same as the heat shield). That project was given up, as well.
NASA continues to ignore the two major problems identified after the Columbia disaster. NASA cannot disguise its glaring failure to complete the major safety objectives assigned to the agency after Columbia, and recklessly places shuttle crews at risk.
Clearly, NASA is back to its old, lethally slack behavior. Besides, NASA is eager to begin phaseout of the remaining shuttles. So, why spend more time or money on the problem? Just hope it will go away.
Heckuva job!
People say it''s a matter of pride to have people in orbit. Yeah, it''s a matter of pride like it''s a matter of pride to have Woody Harrelson chained to a redwood trying to save it. There are other needs in this country, and we have better things to do with our scientists than blowing them up.
It would have worked every time, and saved jet fuel to boot...
---
Incoherent rants from ignorant GOP bozos should not surprise us, but Demslie really needs to move his mindset into the 21st century and discover his real enemies.
For example, the PRC is the world''s richest communist dictatorship-- richer and fatter after Bush policies promoting wholesale export of American-based jobs. Thanks to such policies, Communist China is the biggest creditor of the government of the United States.
How unpatriotic of Bush! Yet not surprising, since both Bush and Beijing regimes claim a country''s leadership is a power unto itself. Not since Nixon has a president displayed such contempt for the rule of law and the interests of the American people.
Bush is the individual who, in November, 2005, facing an assembly of party members critical of his NSA spying program, bristled like a teenager caught drinking after curfew-- "Stop throwing the Constitution in my face! It''s just a GD)((#@*! piece of paper!"
Is this figure, who claims to be president of the United States, the same who pledged an oath to "protect, preserve and defend" the document he calls a "GD)((#@*! piece of paper"?
Okay those statements are all 100% wrong. If you are going to make up science and fabricate facts, you oughta try to keep them in the range of believable, despite Bush&Co example.
The space shuttle uses less jet fuel than a Boeing 787 does traveling between Chicago to New York.
:)
Cursing and throwing insults under cover of the anonimity of the internet. You would not speek that way to someones face least they lay you out as with any mouthy punk. I am not a liberal, not a dem. or rep. I am however a conservitive. A true fiscal con. I don''t believe in spending money you don''t have on things you don''t need. There is a reason these things are mutually exclusive and you have bought into it hook line and sinker. That is polititions of any label. The idea here is to divide the people along any lines that present themselves to continue the childish bickering and divert attention from the sale of our great nation to the highest bidder. Try engaging in an intellegent debate sometime and you might find that our views and priorities are not all that different.
The cost of a single space shuttle launch taking into consideration the cost to build the shuttle and launch facilities, and the expected end of the program in 2010 is $1.5 billion. The cost of a Soyuz launch including construction and facility costs is $50 million, or 1/30 the cost of a shuttle launch.
The problem of debris shedding from the main fuel tank of the shuttle has NOT been resolved, so it''s more a matter of blind luck if there is no damage to the landing vehicle. The Soyuz does not have this problem and is therefore much less likely to kill astronauts in the future.
Soyuz is much simpler, and can be launched with far less preparation than a shuttle. The Russians think nothing of selling extra seats to offset launch costs.
Very few new discoveries are coming from the space station since the Soviets logged so much time in orbit already.
It costs $1.5 billion to send astronauts to literally go around in circles! NASA has a dedicated TV channel, and if you''ve ever seen it, it''s the best cure for insomnia going. The people at mission control sound like they''re describing the process for cleaning a clogged drain.
The Mars Rovers have gone to Mars and send back countless pictures, have outlasted their expected lives, and actually do and see something new every day. They cost $450 million to build and launch. They don''t develop greasy hair, grin and wave at cameras, or poo into a vacuum cleaner, but they''re frankly more interesting than the shuttle and space station program.
---
Demslie should acknowledge his own screaming. If Demslie complains about the complaints, that is not a complaint?
Those affiliating themselves with the GOP should consider carefully the mounting criticisms of Bush and his policies that seem to be everywhere.
Such criticisms are more than material for a Bush-era post-mortema-- they indict Bush for not only his incompetence and vain, destructive ambition, but extreme abuse of the political process.
---
Thank you for the interesting comments. On human vs. machine probes of space, I suspect when it becomes painfully obvious a human cargo is an insufferable burden to mission design, someone at NASA quietly will move the grandstands to a pasture somewhere, decommission most (not all) of the spacesuits, and let machines come into their own.
Machine intelligence and vision have been a long time coming, but follow the same script as the original uneasy drama between NASA astronauts and the machine which put them into orbit. As Mercury, Gemini and Apollo programs matured, each assigned machines much more of the burden of spacecraft management.
Media overplay the astronauts, and often underplay the machine missions, but considering what has been accomplished in defining our solar system and galaxy, the machines win-- probes down.
NASA always has been invaded by politics, and some suspect our shuttle losses were, at least in part, due to some impatient presidents who wanted a public fireworks display. And, of course, Apollo 13 convinced many only a human crew could save a mission. But in the main, the days of astronauts are nearing an end.
this is why NASA does not Have the Confidence of America and why we need to overhaul the dead weight and get some real scientists who actually give a sh-t to run NASA. this GUY is a dweeb and I can not believe he would make such a statement.
-
by goldesprit
December 8, 2007 5:01 AM PST
- Read "Riding Rockets" by Astronaut Mike Mulaine.
-
Reply to this comment
-
See all 31 CommentsHe gives an excellent wrenching account of what its like to sit on one of these shuttles on the pad, and then ride it into space. Not sugar coated.
Not for the timid.