Nasa chiefs 'repeatedly ignored' safety warnings

[CaliGirl]

Fears of a catastrophic shuttle accident were raised last summer with the White House by a former Nasa engineer who pleaded for a presidential order to halt all further shuttle flights until safety issues had been addressed.
In a letter to the White House, Don Nelson, who served with Nasa for 36 years until he retired in 1999, wrote to President George W. Bush warning that his 'intervention' was necessary to 'prevent another catastrophic space shuttle accident'.

During his last 11 years at Nasa, Nelson served as a mission operations evaluator for proposed advanced space transportation projects. He was on the initial design team for the space shuttle. He participated in every shuttle upgrade until his retirement.

Listing a series of mishaps with shuttle missions since 1999, Nelson warned in his letter that Nasa management and the Aerospace Safety Advisory Panel have failed to respond to the growing warning signs of another shuttle accident. Since 1999 the vehicle had experienced a number of potentially disastrous problems:

· 1999 - Columbia's launch was delayed by a hydrogen leak and Discovery was grounded with damaged wiring, contaminated engine and dented fuel line;

· January 2000 - Endeavor was delayed because of wiring and computer failures;

· August 2000 - inspection of Columbia revealed 3,500 defects in wiring;

· October 2000 - the 100th flight of the shuttle was delayed because of a misplaced safety pin and concerns with the external tank;

· April 2002 - a hydrogen leak forced the cancellation of the Atlantis flight;

· July 2002 - the inspector general reported that the shuttle safety programme was not properly managed;

· August 2002 - the shuttle launch system was grounded after fuel line cracks were discovered.

http://www.observer.co.uk/international/story/0,6903,887236,00.html

[2nd_Amendment]

And here comes the "Evul NASA" finger pointing.

*sigh*

[ThomasIsUnderrated]

Don't forget the "It's Bush's fault" finger pointing.

[PaulRevere]

Oh, Gawd, I can already see Hillary standing on the Senate floor again with a NY Post newspaper headline reading, "BUSH KNEW!"

[CaliGirl]

Did anyone else read that this shuttle was over 20 years old and should have been out a long time ago?

[2nd_Amendment]

The shuttles are refit regularly. None of them are the same birds they were when they were built. With proper maintenance 23 years is nothing.

[CaliGirl]

[ QUOTE ]
2nd_Amendment said:
The shuttles are refit regularly. None of them are the same birds they were when they were built. With proper maintenance 23 years is nothing.

[/ QUOTE ]

Can you back that up? Because I don't recall reading that!

[aresian]

From FoxNews

"Since 1988, Columbia went through more than 1,540 modification packages and, due to advances in thermal protection technology, Columbia eventually flew with 5,550 fewer tiles than were carried on its first mission."

And from www.chron.com (http://www.chron.com) a 1985 article...
"The space shuttle Columbia, reworked from front to back since finishing test flights two years ago, was scheduled for launch today, but clouds and stiff winds were keeping the event uncertain. "

And of course all shuttles were reworked after the Challenger disaster in 1986

[CaliGirl]

OK, I can back up what I read earlier today:

[i]On Jan. 28, 1986, space shuttle Challenger exploded shortly after liftoff. Columbia was NASA's original space shuttle, blasting off for the first time on April 12, 1981. Since then, Columbia completed 27 successful missions, logging 284 days, 19 hours, 19 minutes in space before the current mission got underway. The other shuttle's in NASA's fleet – Discovery, Atlantis and Endeavour – remain operational, but obviously grounded until the cause of today's disaster are determined. All told, the shuttle fleet logged 1,015 days, 14 hours, and 15 minutes of flight time in the 112 flights going into Columbia's mission.

The next planned flight by shuttle Atlantis will not fly until engineers determine what went wrong today. Beyond that, it's not yet clear what effect the loss of one of NASA's four space shuttles will have on the launch schedule.

Columbia, NASA's oldest, heaviest space shuttle, does not make routine flights to the space station because it is unable to carry heavy payloads to the station's orbit. But NASA had planned to launch Columbia to the station on its next flight in November.

http://www.washingtonpost.com/wp-dyn/articles/A10088-2003Feb1.html

[The_Finman]

[ QUOTE ]
NASA retiree, Jose Garcia, who was a technical assistant, did not want to speculate Saturday on a possible cause but said budget cuts throughout the 1990s resulted in the elimination of many safety checks and balances during launch preparations. He went public with his concerns, all the way to President Clinton, in fact, but said nothing changed.

http://www.foxnews.com/story/0,2933,77303,00.html


[/ QUOTE ]

[Gone_with_the_Wind]

I beginning to lose all respect for the "UK's most respected magazine". Everything I've read put out by The Guardian lately sounds like liberal hogwash.

[Gone_with_the_Wind]

Cali, I've got pictures of myself and my family standing next to the Columbia (the first shuttle ever built) and me touching it. A good friend of mine was the first female EVER to work on a project like this.

The Columbia was in EXCELLENT condition. It had been completely rebuilt.

[CaliGirl]

[ QUOTE ]
The_Finman said:
[ QUOTE ]
NASA retiree, Jose Garcia, who was a technical assistant, did not want to speculate Saturday on a possible cause but said budget cuts throughout the 1990s resulted in the elimination of many safety checks and balances during launch preparations. He went public with his concerns, all the way to President Clinton, in fact, but said nothing changed.

http://www.foxnews.com/story/0,2933,77303,00.html


[/ QUOTE ]

[/ QUOTE ]


He went public with his concerns, all the way to President Clinton, in fact, but said nothing changed

I rest my case!

[Gone_with_the_Wind]

History of the Columbia (http://science.ksc.nasa.gov/shuttle/resources/orbiters/columbia.html)

http://science.ksc.nasa.gov/shuttle/resources/orbiters/columbia.gif

On September 24, 1999, Columbia was transported to Palmdale California for its second ODMP. While in California, workers will perform more than 100 modifications on the vehicle. Columbia will be the second orbiter outfitted with the multi-functional electronic display system (MEDS) or "glass cockpit". Last year, Shuttle Atlantis had the full-color, flat-panel displays installed on its flight deck during an OMDP. The new system improves crew interaction with the orbiter during flight and reduces the high cost of maintaining the outdated electromechanical cockpit displays currently onboard. (Reference KSC Press Release 74-99)

[**DONOTDELETE**]

I think the problem here is more likely to be an old creeky NASA management that needs to be refit more than its ships. Most of our managerial caste has become too 'team oriented and goal centered' for its own good, downplaying lesser concerns like Truth and objectivity which modern managerial methods disrespect these days. Engineers with decades of experience all too often seem to be ignored in favor of political concerns for the managerial Brahmins.

But in all likelihood, this was just an accident that no one could have avoided; just dumb bad luck.

Just the same, it is a good opportunity to re-evaluate NASA's managerial methods and technical consent procedures.

[CaliGirl]

Gone,

I read your reply, but can't explain today.

I just know of what I read:

Columbia was NASA's original space shuttle, blasting off for the first time on April 12, 1981

It's old...reason for my reasoning, I guess. I don't know if we will ever know the reason.

Does anyone else agree it's old for the trip it takes into space? Am I clueless for thinking this way? Think of the power, the travel it goes through.

I am just thinking out loud right now. It's so boggling to the mind!

[Gone_with_the_Wind]

Cali, All I've got to say is that the Columbia is NOT the same bird it was in 1981. In fact, it is more up to date than all the others. It's a brand new bird.

[Rhino]

[ QUOTE ]
CaliGirl said:................Since 1999 the vehicle had experienced a number of potentially disastrous problems:

· 1999 - Columbia's launch was delayed by a hydrogen leak and Discovery was grounded with damaged wiring, contaminated engine and dented fuel line;

· January 2000 - Endeavor was delayed because of wiring and computer failures;

· August 2000 - inspection of Columbia revealed 3,500 defects in wiring;

· October 2000 - the 100th flight of the shuttle was delayed because of a misplaced safety pin and concerns with the external tank;

· April 2002 - a hydrogen leak forced the cancellation of the Atlantis flight;.............................

· August 2002 - the shuttle launch system was grounded after fuel line cracks were discovered.

[/ QUOTE ]
I think they sort of torpedoed their own premise with this list. These are examples of how the system worked to prevent any shuttle flights with potentially dangerous defects from flying. This is how the system is supposed to work, not a problem that needs to be fixed.

[ QUOTE ]
CaliGirl said:................Does anyone else agree it's old for the trip it takes into space? Am I clueless for thinking this way?

[/ QUOTE ]
No, you're not clueless. These are quite rational questions for someone not familiar with aerospace vehicles, and there are certainly many other people out there wondering the same things. Barring serious metal fatigue in the major structural members, an aircraft (and the shuttle is an aircraft) can theoretically be kept flying safely for an indefinite period. As far as the metal fatigue is concerned, the shuttles are regularly tested for such defects using several different NDI (Non-Destructive Inspection) techniques, and all cracks are repaired as necessary, as well as a running database being maintained on the strength and integrity of the metal itself. Beyond those major structural members, just about the entire remaining aircraft could be completey replaced over it's lifetime. Columbia itself received a major rebuild in 1999 that involved stripping it down to nearly the frame itself and being rebuilt as necessary.

23 years may seem like a long time because when most Americans hear the term "vehicle", they think of cars, and that makes 23 years seem like one hell of a long time. The Air Force has retired aircraft that were in active service more than forty years since they were originally built, and not that long ago the average age of airliners was approaching 30. In other words, the age related problems you are so rightly wondering about are exactly what they look for when they inspect and refurbish the shuttles.

Think of it this way. If you had the resources to have maybe a Ford Explorer of yours completely dissasembled every three years, have every part meticulously inspected and refurbished or replaced as necessary, have every speck of corrosion removed or repaired, have all parts of the vehicle repainted or recoated as they were in the factory, and have any new technology parts or features that were available re-installed instead of the originals, how long do you think that Explorer would last and be able to be safely driven? A lot longer than it would as things are now, huh? That's the general scenario for aircraft and shuttles. It doesn't prevent someone from missing something, but that can happen no matter what the age is, and they actually look for more as the aircraft gets older.

[2nd_Amendment]

Another reference for Cali: The B-52 first flew in...'58? Roughly then, making it almost 50 years old. The Air Force expects to keep them in the fleet for potentially another 50 years.

There are STILL DC-3's flying cargo and commercial runs. That's 1920's technology and it still has one of the best safety records in aircraft history. The SR-71 Blackbird is almost 40 years old now. There are no plans to ever retire it due to hours logged. It's sole criteria is cost effectiveness. The Blackbird, at least a couple, will almost certainly still be flying at the end of this century unless budget cuts kill them.

"Age" is a consumerist driven concept. One the government takes advantage of to justify the latest whiz-bang they think they need. The public buys it because that Chevy in the drive that they don't take proper care of can only last 10 years so everything must be like that. As for myself, I don't drive 'em till they're at least ten or twenty years old.

[EagleTed]

[ QUOTE ]
2nd_Amendment said:

"Age" is a consumerist driven concept. One the government takes advantage of to justify the latest whiz-bang they think they need. The public buys it because that Chevy in the drive that they don't take proper care of can only last 10 years so everything must be like that. As for myself, I don't drive 'em till they're at least ten or twenty years old.

[/ QUOTE ]

A visit to any car show proves your point. There are Model A's and T's that are in better shape today then when they rolled off the assembly line.

[**DONOTDELETE**]

While I do agree that proper maintenance can keep a vehicle going almost indefinately; the roughness and high temperatures that the shuttle engages in, with its rapid heat expansion and contraction, is far worse than what any public road can do to a Model T.

Even the B-52's dont take stress as much as the Shuttle does.

I can understand the gist of what you say, but the complete rebuilds that they do seems more than needed every 10 years or so.

If my car was having parts falling off of it two or three times a year, I'd take it back to the dealership.

[Rhino]

rglencheek,
The rapid expansion and contraction due to heat is almost completely limited to the ceramic tiles, which are regularly replaced. Relatively very little of that heat actually transfers to the structural body of the shuttle itself. The shuttle skin itself also has temperature sensors installed to alert NASA if any unduly high heat ever does make it to the skin so they can perform detailed inspections if necessary to look for exactly the type of damage you mention. You are correct that the shuttle experiences different stresses than do B-52s, but that is why the shuttle inspections are designed specifically for those kinds of stresses. I used to run an aircraft inspection section that did exactly this, and every different type of aircraft had different inspection criteria that was designed with the environment for that specific aircraft in mind. The same is true for the shuttle.

Didja know you can heat those tiles to several thousand degrees and drop them into your hand within five seconds without being burnt? Amazing what they can do these days!

[Warlady]

Rhino what are the tiles made of?

[Keith J]

The tiles are nothing like what you may have in your shower/bathroom. They are made from nearly purer silicon dioxide, sand if you will, that has been made into a low-density foam. The tiles will float on water (thank goodness) due to this porosity. This material feels like Styrofoam but its less forgiving. Drop it and it dents, chips or fractures.

The tiles on the underneath side are further protected with a thin coating of silicon carbide glaze to further enhance their thermal properties by aiding in the radiation of heat. The most critical areas, namely the leading edges of the wings, tail and nose, have an additonal layer of a carbon-carbon composite covered with a layer of silicon carbide. This material is incredibly tough and impact resistant.

The tile are literally glued onto a felt pad which is bonded to the skin of the shuttle. The glue? Its a high-temperature silicone rubber much like the high-performance silicone rubber bathroom caulk commonly applied around bath tubs.

My prediction? NASA will invest in multiple layers instead of
one fragile layer.

[Warlady]

Thanks Keith. Yes, everytime there is a catastrophic event NASA learns from it and makes it better.

[**DONOTDELETE**]

But it would seem that the insulation on the fuel cells are not so rigorous, and the cold temperatures may have loosened the foam and that impact at hundreds of miles an hour can loosen, in turn the ceramic tiles.

It clearly demands that NASA incorporate some form of tile maintenance and inspection once in orbit. Otherwise, returning to Earth remains a crap shoot.

[Keith J]

[ QUOTE ]
rglencheek said:
But it would seem that the insulation on the fuel cells are not so rigorous, and the cold temperatures may have loosened the foam and that impact at hundreds of miles an hour can loosen, in turn the ceramic tiles.

It clearly demands that NASA incorporate some form of tile maintenance and inspection once in orbit. Otherwise, returning to Earth remains a crap shoot.


[/ QUOTE ]

The fuel tank insulation is designed to be disposable. There is the problem. Remember the first ~10 missions? Bright white tank? Well, it was a different insulation system and painted. Ditching the paint saved serious pounds...don't recall how much but it could have affected the insulation system by allowing moisture to infiltrate the urethane/styrene insulation system. The external tank is a cryogenic liquid storage unit with temperatures of 22 to 84 Kelvin (-420 and -309 F), depending on which liquid...oxygen goes in the forward tank.

NASA had a tile repair system, looks like a giant caulking gun. Astronaut Truly used it in a photo shoot for The National Geographic magazine, issue is March 1981(looked it up myself). What they are saying is they had no mission specialist capable of using it. Did NASA assume a low risk posture and not stow one on board? Did the system not pass technical merit?

[Rhino]

[ QUOTE ]
rglencheek said:
But it would seem that the insulation on the fuel cells are not so rigorous, and the cold temperatures may have loosened the foam and that impact at hundreds of miles an hour can loosen, in turn the ceramic tiles.

[/ QUOTE ]
Well, from the fuel tank to the shuttle it probably would not have accelerated more than around 50 MPH or so, but your point is well taken. They had similar concerns about ice chunks earlier on, because areas where liquid oxygen was used had ice form on the skin, and this would break loose on takeoff. Then again, if the tiles can hit the atmosphere at 25,000 MPH by design, I'd say they've gotta have some pretty damn good resilience of some sort! Seems like something that could withstand that kind of torture oughta be able to shrug off a piece of rather soft insulation at something below 100 MPH.

[ QUOTE ]
rglencheek said:
It clearly demands that NASA incorporate some form of tile maintenance and inspection once in orbit. Otherwise, returning to Earth remains a crap shoot.

[/ QUOTE ]
If they had EVAs scheduled, then I think such an exterior inspedtion would be a given. If they had to add an EVA to a mission that otherwise had none, it might require extra effort or resources beforehand, but I agree it would be worthwhile though. One thing makes me curious though. Usually there is not another shuttle standing by that could be launched in a timely manner. If they found damage that would prevent re-entry, I wonder what they'd do? Probably crash the international space station for now. Then order out for extra pizza I guess.

[Warlady]

Rhino there was a NASA reporter on earlier that said they weren't at the right pitch or something to rendevous with the space station but had they believed that this would have happened they would have sent up another shuttle to rescue them in about a week to 8 days and that it would have been risky. Maybe now they'll start working on rescue plans for future flights. Seems to me if the tiles are only 6"x 6" they take some spares and a glue gun and do a space walk to repair it. An interoffice memo just released said there was a 8" by 30" gash in the tiles under the left wing made by that insulation that broke off. Could that be enough of a breach in the heat shield to cause the thermal damage which resulted in it breaking up the way it did?

[Keith J]

Think of an area that large heated to 3000 F. That is a energetic fire. Now think of putting that anywhere on the surface of a flying plane. Keep in mind aluminum loses most of its strength past 350 F.

Aerodynamics also play a big part. That size of flow disruption would easily affect trim.