More of the same at NASA

[Kopji]

NASA Unable to learn from past mistakes
(Will Griffin run for President in 2008?)

On the eve of the shuttle Discovery's scheduled launch, NASA Administrator Mike Griffin acknowledged Friday that he is "playing the odds" by giving the go-ahead for the mission despite continuing concerns about foam-insulation debris...

Simulations of the tank's aerodynamics has indicated that debris from the ice/frost ramps could pose a very slight risk of catastrophic damage - leading NASA's chief engineer and chief safety officer to declare that they were "no-go" for Discovery's launch until the ramps are redesigned...

Even Griffin acknowledges that the ramps need to be fixed eventually — but he said that, in the long run, holding up shuttle flights for a redesign would pose more risk than going ahead with the launch. Presented with that reasoning, the dissenters said they understood the decision and declined to pursue an appeal...


"You're not going to like this, and I'm sure I'm not going to like how it sounds in print, but we are playing the odds," Griffin answered. "What you pay us for, as taxpayers, is to understand those odds in great detail. When we say 'playing the odds,' what we're talking about is risk management. And to engineers, risk is expressed in terms of probability and statistics. I think we've got a team here that understands that discipline as well as any group I've seen."

Griffin said that the go/no-go decision had to strike a balance involving risks to the crew, as well as cost risks and schedule risks.

http://www.msnbc.msn.com/id/13637213/


Well he's right, his attitude does not look good in print. This seems a lot like the same attitude that got two entire shuttles and their crews destroyed. NASA management's confidence in themselves knows few limits.


"What you pay us for, as taxpayers, is to understand those odds in great detail. When we say 'playing the odds,' what we're talking about is risk management.

That is the part that rubs me the wrong way. Ah! NASA's poor management decisions are the taxpayer's fault. Well he's wrong about that, his logic and reasoning are flawed. He does not need to launch for me.

[WildCat]

Does anyone know why we're still flying the space shuttle any more? Seems to me this horse has run its race and it's time to move on.

[Apollyon]

Are you suggesting that launching people attached to the world's largest firework should be without risk?

[gumboot]

What, honestly, is the big deal?

Space Travel is not a sunday drive. The dangers are enormous. Everyone involved knows this. Accidents happen. And with space travel, when accidents happen people die.

If man only did things that had no risk none of us would ever do anything. All this "making it totally safe" BS is helping no one.

Why doesn't NASA just come out and say "Hey, this stuff is highly dangerous. Sometimes there are accidents. And there will continue to be accidents in future. It's part of the deal. Every time we send seven astronaughts into space we all know they might never come home."

Human advancement has its foundations on the wreckage of accidents and failed attempts.

-Andrew

[Cylinder]

Of course, this echoes many other responses, but what's a little piling on between freinds...

Does anyone remember which SST mission was the last to be free from risk?

What do the NASA acronyms LOM, LOV and LOC stand for in relation to manned space flight? How are these values calculated?

[Kopji]

I don't disagree, but the attitude seems a bit cavalier. After all, it is because of not listening to the engineering staff we have lost two shuttles and what, 14 dead astronauts?

Losing 20% of 5 shuttles is one less than sending well over half of the fleet to destruction.

And we are not above doing things for national pride. We smacked a comet on the 4th of July. (Just a coincidence mind you). :rolleyes:

So while I would agree that sacrifice comes with the dangerous territory, is this exploration we are doing or politics? The greatest country in the world sends people into space on shuttles, not dangerous rockets or experimental craft.

('astronaughts' is an interesting typo.)


Far better it is to dare mighty things, to win glorious triumphs even though checkered by failure, than to rank with those poor spirits who neither enjoy nor suffer much because they live in the gray twilight that knows neither victory nor defeat. - Teddy Roosevelt


(I turn my acronyms off at night.)

[gumboot]

I guess it depends a lot on the scenario...

What we don't know is whether it was a case of:

A: No it's too risky
B: Oh harden up, gotta take some risks
A: No really, it's not safe at all, if we launch-
B: I said we're going and that's an order! Do you want me to show everyone those photos of you and that guy from electricals?
A: No sir!
B: Good, then give us the OK for launch
A: Yes sir

or

A: There's still a risk
B: Look, it's a small risk, much smaller than before
A: But if anything happens...
B: They all die. We all know that. They know that. This is dangerous.
A: Okay, you're right, we're good. We can go.

Okay, lame dialogue... :p but you get the idea...we may never know how it went down...

-Andrew

EDT. Typo

[TragicMonkey]

"Cost risks" and "schedule risks"? For the latter, we seem to have plenty of time to get it right. We're not fighting aliens, are we? Do we have to get shuttles up before the enemy mothership arrives? As for "cost risks", NASA isn't supposed to be a business. You put money in, you get science out. It's not supposed to turn a profit, and if it costs a little more to get it right, well, it already costs enormously already. Are you going to buy a $1.5 million dollar mansion then balk at buying a few $10 smoke alarms?

I'm interested in science and think we ought to spend even more on the space program, but I'd rather they send half as many flights that are each twice as safe than send double the flights at half the safety. When in doubt, delay. Too many dead astronauts will kill the program entirely.

[AmateurScientist]

Does anyone know why we're still flying the space shuttle any more? Seems to me this horse has run its race and it's time to move on.

You got it. The simple answer is that government programs are self-perpetuating and hard as the devil to kill.

The shuttle is a 30+ year old technology and idea that serves no legitimate function anymore.

NASA (and Congress) screwed up long ago by not developing and pursuing a feasible follow on program for "routine" manned space flight to step in once the shuttle became obsolete (which happened years ago).

The whole program should have been scrubbed after the Columbia disaster. I truly thought it would be. I'm very sorry it wasn't. My city already has enough public schools named after dead astronauts. We don't need any more.

Are we never going to Mars in this century either?

AS

[Apollyon]

Isn't there a plan in place for a shuttle replacement by 2012, or somewhere thereabout? I agree a replacement should have been developed much sooner, but better late than never.

[zenith-nadir]

The problem is the shuttle program represents design ideas from the 1970s. Vital parts of the shuttle are obsolete, and NASA engineers spend most of their time simply maintaining these vintage technologies to squeeze a few more years out of them. As these obsolete technologies become ever more difficult to find and maintain, the viability of the entire shuttle system becomes threatened, hence the danger of operating the old girl.

[AmateurScientist]

Isn't there a plan in place for a shuttle replacement by 2012, or somewhere thereabout? I agree a replacement should have been developed much sooner, but better late than never.

A replacement is a horrible idea. The shuttle was developed in concept as a precursor to routine travel into space, much like routine terrestrial airline travel. It was hoped at the time that everyday citizens would eventually use it or its successor to travel to and from space stations and/or lunar bases.

In retrospect, it's clear than routine travel by ordinary citizens is a pipe dream, at least for the foreseeable future, which includes all of this century. Not only is there no real need or demand for such travel (as there is nothing to speak of to travel to presently {and I hardly think the ISS qualifies for ordinary citizens}, for one thing), but also we have learned a lot in the past 30 or 40 years about just how many dangers there are inherent in traveling outside our protective atmosphere. Gamma radiation, solar storms, space debris, etc. pose unacceptable risks to ordinary citizens. It is unlikely space travel as envisioned 35 years ago by the visionaries who sold this concept to Congress will entail anything like what they dreamed of. Kubrick's Pan Am spaceplane from 2001 is nothing more than a fairy tale.

As for professional space exploration, the only worthwhile, feasible project for manned space flight in the foreseeable future is a manned Mars mission. The Space Shuttle and any possible replacement for it have no place in such a mission. The Mars mission is a completely different paradigm from a "cheap" reusuable craft for short flight.

AS

[AmateurScientist]

The problem is the shuttle program represents design ideas from the 1970s. Vital parts of the shuttle are obsolete, and NASA engineers spend most of their time simply maintaining these vintage technologies to squeeze a few more years out of them. As these obsolete technologies become ever more difficult to find and maintain, the viability of the entire shuttle system becomes threatened, hence the danger of operating the old girl.

I think the problem is much deeper than that, actually. In contrast, look at the SR-71. It was developed using technology from the 1950s. It was and still is a technological marvel, and remains to this day, as far as we know, the fastest airplane ever. We never lost one, either.

I think so much of the problem remains in a systemic failure in the bureaucracy that is NASA, and the many failures it has made in management, engineering, planning, and budgeting. I say this as someone who knows dozens of NASA and prime and sub contractor engineers, and who grew up in a city which derives its identity and economic prosperity from the U.S. space programs. I should be defending NASA and its contractors, but I'm not.

AS

[Kopji]

I guess we will find out if it was a good decision or not.

I agree it is not so much old technology, it is the execution/decision structure of NASA. I'm not really inclined to take any lessons on risk management from NASA. Safety and quality are their number one goals right behind meeting their delivery schedule set by a political agenda.

Off topic, but the US space program should either be returned to the military or turned over to private industry. Sure there's going to risk, but why pretend it is some kind of government run business? NASA is sort of like FEMA - more of the same kind of politicians making decisions.

[Dr Adequate]

I wonder if Richard Branson will let them borrow SpaceShipThree.

Heck, why don't NASA just ask Scaled Composites to build them an orbital spaceplane? The technology is safer, it's cheaper, it's more reuseable (none of your solid rocket boosters, thank you so much) it has a faster turn-around time --- and Burt Rutan's spaceships look effin' fantastic.

http://img227.imageshack.us/img227/4585/spaceshipone9st.jpg

Admit it, you want one.

[geni]

Heck, why don't NASA just ask Scaled Composites to build them an orbital spaceplane?

Because there is no way Scaled Composites could do it. Orbit is much harder than sub orbital. Temeber the X-15 was pretty much doing what space ship one does back in 1963.

[geni]

The problem is the shuttle program represents design ideas from the 1970s.

Even in the 1970s the desighn made little sense. A manned craft with a heavy lift capabilty is an odity. Only exists for political reasons.

[Apollyon]

A replacement is a horrible idea. The shuttle was developed in concept as a precursor to routine travel into space, much like routine terrestrial airline travel. It was hoped at the time that everyday citizens would eventually use it or its successor to travel to and from space stations and/or lunar bases.
My understanding is that the shuttle was initially intended to haul a crew into space and be reusable with a relatively quick turnaround time to launch. Eventually, compromises reached with the Pentagon to get the Shuttle program funded (it was almost cut as a viable program) required that it carry some fairly hefty payloads. Thus, instead of a sort of passenger car, as it was initially designed, we ended up with a tractor-trailer.

I don't recall the Shuttle ever being any precursor to commercial space travel. Much like commercial air travel, commercial space travel was always left to commercial enterprise to develop.

In retrospect, it's clear than routine travel by ordinary citizens is a pipe dream, at least for the foreseeable future, which includes all of this century. Not only is there no real need or demand for such travel (as there is nothing to speak of to travel to presently {and I hardly think the ISS qualifies for ordinary citizens}, for one thing), but also we have learned a lot in the past 30 or 40 years about just how many dangers there are inherent in traveling outside our protective atmosphere. Gamma radiation, solar storms, space debris, etc. pose unacceptable risks to ordinary citizens. It is unlikely space travel as envisioned 35 years ago by the visionaries who sold this concept to Congress will entail anything like what they dreamed of. Kubrick's Pan Am spaceplane from 2001 is nothing more than a fairy tale.

As for professional space exploration, the only worthwhile, feasible project for manned space flight in the foreseeable future is a manned Mars mission. The Space Shuttle and any possible replacement for it have no place in such a mission. The Mars mission is a completely different paradigm from a "cheap" reusuable craft for short flight.

AS
What you say is possibly true. But look at the difference between the beginning of the 20th century, when we didn't even have powered air flight yet, to just 40+ years later when the first commercial airlines began operations. Rutan has already taken the X-Prize. A lot of money is going into commercial space flight. Once the ball gets rolling it should begin to steamroll relatively quickly.

As to professional space exploration, isn't the new Shuttle design supposed to be able to go to the moon and back so we can begin building a base from which to launch a Mars mission?

[CapelDodger]

Even in the 1970s the desighn made little sense. A manned craft with a heavy lift capabilty is an odity. Only exists for political reasons.
I've never understood why it has such a large payload-bay. Payloads can be thrown up using the old method - a stick of dynamite with a tin-can on top - while people fly up to rendezvous with it. Much simpler and safer.

[Apollyon]

I've never understood why it has such a large payload-bay. Payloads can be thrown up using the old method - a stick of dynamite with a tin-can on top - while people fly up to rendezvous with it. Much simpler and safer.
This might explain it:

http://www.space.com/spacenews/businessmonday_050815.html

By 1970, the White House had lost its appetite for large space programs, Logsdon said. Production of the Saturn 5 was ended, and NASA was told to forget about a space station for the time being.

That forced NASA to seek allies to justify building the shuttle. "The key ally was the national security community," Logsdon said.

The Pentagon agreed to get behind the shuttle provided it had certain characteristics, Logsdon said.

"One of those characteristics was the ability to launch classified payloads that could be up to 60 feet (18 meters) in length" and weigh up to 18,200 kilograms, Logsdon said. "The width of the payload bay was driven by NASA’s desire to eventually build a space station."

Another Defense Department-driven requirement, Logsdon said, was the ability to take off and return to a West Coast launch site after a single polar orbit. Because of the Earth’s rotation, a single polar orbit would not bring the shuttle back directly over its launch site, meaning it would have to glide farther through the atmosphere to land than otherwise would be the case. That drove NASA to add large delta-shaped wings and a more robust—not to mention heavier— thermal protection system to its space shuttle design.
It was a compromise to prevent the Shuttle program from getting canned.

[Dr Adequate]

Because there is no way Scaled Composites could do it. Orbit is much harder than sub orbital. Temeber the X-15 was pretty much doing what space ship one does back in 1963. But SpaceShipThree is already being planned. It is intended to be orbital.

This is just so much a better way to build a shuttle.

[geni]

But SpaceShipThree is already being planned. It is intended to be orbital.

Not really. They are talking about trying if SS2 succees but thats just talk until they try to build the thing. Consider the X-38.


This is just so much a better way to build a shuttle.

Minimal payload means a shuttle equiverlent isn't really practical. If you want a pure manned launch with a low payload you just use soyuz.

[webfusion]

"If you want a pure manned launch with a low payload you just use soyuz."


Soy Vessels on the Launch Pad (http://www.nickelinstitute.org/multimedia/nickel_and_its_uses/nickel_magazine/archives/2005/March_2005/Soy_sauce_tanks_450.jpg)

Weird Image Link

[Azure]

Does anyone know why we're still flying the space shuttle any more? Seems to me this horse has run its race and it's time to move on.

No kidding. Popular Science had a way better design.

As stupid as that sounds, its true. The old junk has to go.

[gumboot]

I think the problem is much deeper than that, actually. In contrast, look at the SR-71. It was developed using technology from the 1950s. It was and still is a technological marvel, and remains to this day, as far as we know, the fastest airplane ever. We never lost one, either.

You lost twenty (http://www.wvi.com/~sr71webmaster/srloss~1.htm) actually.

Much of the lack of replacement for the shuttle seems to be budget... as I understand it the plan, after getting to the moon, was to establish facilities outside the earth's atmosphere - in orbit and on the moon. The primary role of the shuttle was to provision those facilities (bear in mind the shuttle is designed as a cargo vehicle - not a passenger vehicle). Except the ISS programme didn't get the funding it really needed, and no one was overly interested in the moon.

I think a replacement for the shuttle (that is a surface-to-orbit cargo vessel) is still important for any mission to other planets - it makes a lot of sense to build any deeper-space craft in orbit. (As I understood it, this was one of the original intentions of having the ISS and/or moon base)

-Andrew

EDT. Having read others comments... having a remotely controlled craft to take up payload, and a smaller vessel just for crew, makes much more sense. We have the technology now to build entirely computer-operated craft... makes sense.

[webfusion]

Why I absolutely enjoy the JREF Forums can be summed up in the following exchange:

AmateurScientist writes:In contrast, look at the SR-71. It was developed using technology from the 1950s. It was and still is a technological marvel, and remains to this day, as far as we know, the fastest airplane ever. We never lost one, either.

and gumboot responds:
You lost twenty actually.


ZING! Thanks for making my day, andrew.

[Kopji]

I wonder if Richard Branson will let them borrow SpaceShipThree.

Heck, why don't NASA just ask Scaled Composites to build them an orbital spaceplane? The technology is safer, it's cheaper, it's more reuseable (none of your solid rocket boosters, thank you so much) it has a faster turn-around time --- and Burt Rutan's spaceships look effin' fantastic.

http://img227.imageshack.us/img227/4585/spaceshipone9st.jpg

Admit it, you want one.

Yeah I want one.
Watching a launch is on my list... Not too far away.

[AmateurScientist]

Why I absolutely enjoy the JREF Forums can be summed up in the following exchange:




ZING! Thanks for making my day, andrew.

ZING? I didn't realize it was a competition.

I made an error. Zing, huh? I suppose my faulty memory, rather than my Googling skills, caused me to erroneously believe we never lost an aircraft, when I must have been remembering the Air Force's record of not losing a crewmember, and that none of the planes were ever shot down. They could fly faster than missiles and bullets, and their mission altitudes were extremely high.

AS

[gumboot]

ZING? I didn't realize it was a competition.

I made an error. Zing, huh?


I suppose you could give them the benefit of the doubt and assume they feel the forums are worthwhile because they have the constant opportunity to learn new things...

;)

-Andrew

EDT. While that might not have been their meaning...it's certainly something I enjoy about this place... I have had many of my misconceptions (especially regarding aspects of the USA) corrected here... resulting in a net profit to my overall knowledge :D

[AmateurScientist]

I suppose you could give them the benefit of the doubt and assume they feel the forums are worthwhile because they have the constant opportunity to learn new things...

;)

-Andrew

EDT. While that might not have been their meaning...it's certainly something I enjoy about this place... I have had many of my misconceptions (especially regarding aspects of the USA) corrected here... resulting in a net profit to my overall knowledge :D

I agree with your sentiment, and perhaps that's we he meant. I just didn't appreciate the ZING remark. I didn't take your correction as a ZING. I agree with you that you were contributing to a misconception and correcting a mistake. There's nothing wrong with that. We should encourage that.

It's one thing to correct someone. It's another to treat it as if you have just trounced that someone in a verbal smackdown. There was nothing in my posts in this thread to merit such treatment on his part.

Perhaps you are right in that he didn't mean it that way. If not, then I apologize to both of you for my taking it the wrong way.

AS

[Mr. Skinny]

Of course, this echoes many other responses, but what's a little piling on between freinds...

Does anyone remember which SST mission was the last to be free from risk?

What do the NASA acronyms LOM, LOV and LOC stand for in relation to manned space flight? How are these values calculated?
I assume they stand for Loss of Mission, Loss of Vehicle, and Loss of Crew. I doubt they have a "value" that can be calculated, although individual values for each event or series of event that could lead to LOM, LOV, or LOC could be assigned, allowing one to calculate the probablility of those top events occuring. However, given the nature of your first question, and its obvious answer, I'm not sure you were serious about your second one.

[Cylinder]

I assume they stand for Loss of Mission, Loss of Vehicle, and Loss of Crew.

Yup.

I doubt they have a "value" that can be calculated, although individual values for each event or series of event that could lead to LOM, LOV, or LOC could be assigned, allowing one to calculate the probablility of those top events occuring.

They actually do calculate a probability value as part of the planning cycle in very much the manner you describe.

However, given the nature of your first question, and its obvious answer, I'm not sure you were serious about your second one.

Yea, the questions only become un-serious when you understand the risk involved with human spaceflight. For Griffin to assert no chance for these events would be a bare lie. Absent that, you are left with managed risk.

[Rob Lister]

Everyone has their favorite charity, SETA and NASA are mine. Pipedreams can be realities.

Shuttle? It is old, it is dangerous, It fairly sucks in terms of what a newly designed one could and would do...I watch every launch I can.

Scrap it after you replace it. I like it.

[Mr. Skinny]

Yup.
Cool.
[quote=Cylinder]They actually do calculate a probability value as part of the planning cycle in very much the manner you describe.
I'm a System Safety Engineer for the Air Force. Never had to do a hazard analysis on anything as complicated as the Shuttle, but I'm quite aware of how the process works.
Yea, the questions only become un-serious when you understand the risk involved with human spaceflight. For Griffin to assert no chance for these events would be a bare lie. Absent that, you are left with managed risk.
I'm not sure I read it the same way as you. Are you thinking he lied, or are you saying that if he hypothetically had said that, it would be a lie? I saw nothing that looked like that assertion in his comments.

"You're not going to like this, and I'm sure I'm not going to like how it sounds in print, but we are playing the odds," Griffin answered. "What you pay us for, as taxpayers, is to understand those odds in great detail. When we say 'playing the odds,' what we're talking about is risk management. And to engineers, risk is expressed in terms of probability and statistics. I think we've got a team here that understands that discipline as well as any group I've seen."
Sounds to me like he's saying "We looked at all the risks, and feel the risk is acceptable, but it's still a roll of the dice". The only beef I have with his comment should have been "risk is expressed in terms of probablility and severity." This can be quantified in some cases, but in other cases, it's sometimes a best guess based on the input of experts in different disciplines, but I don't want to get into that too heavily at this point.

Anyhow, you cleared up some things, and re-confused me on another. :)

[Cylinder]

I'm not sure I read it the same way as you. Are you thinking he lied, or are you saying that if he hypothetically had said that, it would be a lie? I saw nothing that looked like that assertion in his comments.

Sorry. It would have been clearer to have said "If Griffin had asserted..."

I don't think he lied at all. It would have been a transparent lie - given the results of the last 2 STS missions - to assert no risk or very little risk as opposed to managed risk.

[Mr. Skinny]

Sorry. It would have been clearer to have said "If Griffin had asserted..."

I don't think he lied at all. It would have been a transparent lie - given the results of the last 2 STS missions - to assert no risk or very little risk as opposed to managed risk.
Thanks, Cylinder. The engineer in me wanted to make sure I understood what you were saying.

[Kopji]

Interesting link on the Blackbirds. I'd never heard that many were lost either.

The main safety issue at hand is the foam though, and not the older technology of the shuttle itself. This is the same stuff where NASA management could not accept that something that soft could actually be a problem, until they saw for themselves what it could do when shot from a cannon at the speeds in question.

So here the shuttle sits on the launch pad, and before it is even moving there are pieces of foam falling off: The same stuff that caused enough damage to destroy a previous flight with loss of all crew.

The verbal musing this morning is " 'whew', well that piece was not big enough to do damage so maybe we should go". This does not seem like a real head scratching kind of safety decision, but I guess I'm not a qualified expert.

[Mr. Skinny]

he main safety issue at hand is the foam though, and not the older technology of the shuttle itself. This is the same stuff where NASA management could not accept that something that soft could actually be a problem, until they saw for themselves what it could do when shot from a cannon at the speeds in question.

So here the shuttle sits on the launch pad, and before it is even moving there are pieces of foam falling off: The same stuff that caused enough damage to destroy a previous flight with loss of all crew.

The verbal musing this morning is " 'whew', well that piece was not big enough to do damage so maybe we should go". This does not seem like a real head scratching kind of safety decision, but I guess I'm not a qualified expert.
Actually, Kopji, it probably is a real head scratcher, and there are probably dozens of safety engineers sitting around right now trying to re-assess the risk, as we speak (type).

Based on what I heard on the news tonight, though, I think you probably have a reasonable point though. The news (ABC) said they thought it was from the filling and draining of the hydrogen. That would indicate a failure due to thermal stress. That sounds like something that could have been forseen.

If it's something else, well, who knows.

I'm watching with great interest to see what develops.

[Kopji]

Actually, Kopji, it probably is a real head scratcher, and there are probably dozens of safety engineers sitting around right now trying to re-assess the risk, as we speak (type).

Based on what I heard on the news tonight, though, I think you probably have a reasonable point though. The news (ABC) said they thought it was from the filling and draining of the hydrogen. That would indicate a failure due to thermal stress. That sounds like something that could have been forseen.

If it's something else, well, who knows.

I'm watching with great interest to see what develops.

I hope everything goes ok. I've been a follower of the space program from the Apollo days.

I was being a little sarcastic on the 'head scratching': I don't really understand where their confidence in going forward is coming from. They say they are following objective standards, but they are adjusting the standards to fit what they want to do.

A purpose of the mission is to test some repair procedures and safety features, so maybe their thinking is that if anything 'low to medium risk' bad happens they can get experience fixing it. (Another destroyed shuttle and they are all looking for work anyway). I suppose that might make sense, but I'd pass on the tourist tickets, put me on a later flight...

There are a number of things that a 'normal business' might object to in how this decision is being made. Something to be careful of is a management style that suppresses dissent, or in this case causes dissent to be waged something like a battle. I've never heard of that style being used to evaluate safety concerns.

Not to lecture NASA, but product 'safety' is something similar to 'quality'; it is integral to what you are doing, not tacked on. Clearly in the Shuttle this is not the case, safety is something that has been sort of re-engineered and retrofitted as unforeseen failures occur. The Shuttle program did not seem quite so 'experimental' in nature when it began.

On Sunday, rain showers swept over Discovery at the pad, and Shannon said rainwater most likely entered a small crevice in the feed-line bracket foam. That trapped water could have frozen and expanded during contact with the chilled tank, then thawed as the tank was drained — opening the crack further.

The cracked material was likely flexed when the launch pad's rotating service structure was moved back toward the orbiter, leading to the break-off of the small foam piece, Shannon said.
http://www.msnbc.msn.com/id/13666974/

I just don't get how they can be confident that more damage was not done, or that there are not more cracks that escape visual inspection.

...By Monday evening, NASA's management team agreed to go ahead with launch preparations. Gerstenmaier said there was "lots of discussion from many people during the review ... but essentially no dissenting opinions with where we're going." Among those in attendance was NASA Administrator Mike Griffin, he said.

It's the phrases like I boldfaced that are bothering me. Maybe those are more common in government enterprises, but I'd have my roasted ass handed to me if I put that phrase in a report. You document your discussion and affirm any dissent. I have no idea what 'essentially' means in terms of dissent, it sounds like an equivocation. Does it mean that there was dissent but not any they felt overrode the mission?

[gumboot]

With the whole foam thing...

It's not like Columbia was the first time ever that foam fell off during launch. It always falls off. It may be there's no realistic way to prevent it. It was just with Columbia the falling off caused key damage.

And a thing to bear in mind - that damage had no affect on the mission whatsoever UNTIL RE-ENTRY. I have not seen evidence that foam coming off during launch poses any threat to the mission prior to re-entry.

They have developed processes for inspecting and reparing damage prior to re-entry.

Surely this addresses the issue? Foam falls off during lift-off, as per normal. There's a 1 in 1 million or whatever chance of it causing damage to heat tiles. In the event of such happening, the astronaughts detect the damage during their inspections and repair the damage. No harm done.

It seems senseless to attempt to avoid all damage whatsoever (especially as that seems impossible). There will always be risk of the shuttle receiving damage during the mission. A single screw or a bit of rock in orbit is capable of inflicting equally deadly damage.

The solution, to me, is YES, do as much as realistically possible to reduce damage risk in lift off. But more important is to provide the astronaughts the capabilities to inspect and repair their craft in space. to me this seems to be NASA's failing - not the design of a craft that isn't 100% safe.

Surely after Apollo 13 they should have learned that Astronaughts needed the equipment and resources with them to repair damage to their craft.

Also, while the Shuttle is "old" it is important to note that in aviation terms (it is an aircraft of sorts, afterall), it's not really *that* old - especially given its constant makeovers.

This is not a perfect comparison, but as late as 2001 the RNZAF were operating A4K Skyhawks, 40 years of age, yet still rated to be in "excellent" condition, comparable with a modern F-16A. We had upgraded these craft, sure, but we didn't have an army of experts ready to improve them after every single flight.

I agree the shuttles need replacing, but I would be cautious in claiming they were too old to do their mission any more, or somehow obsolete. They're just not ideal (and at some point they *will* be too old).

-Andrew

[Dr Adequate]

Not really. They are talking about trying if SS2 succees but thats just talk until they try to build the thing. Consider the X-38.

Minimal payload means a shuttle equiverlent isn't really practical. If you want a pure manned launch with a low payload you just use soyuz. They've tested the innovative bits: the methods of launch and re-entry.

For orbital capacity and a greater payload, you just need a bigger ship with more fuel.

It's not exactly ... oh, hold on. It is, isn't it?

But it's not brain surgery.

They do seem to think they can build SpaceShipThree and make it work. If I were NASA, I'd at least commisssion them to produce a design.

[Checkmite]

Since I am not intimately familiar with all of the variables involved in launching a shuttle, and therefore am unable to examine the risk factors myself, I'm not sure I'm really qualified to second guess these guys. It should be noted that the dissenters withdrew their no-go; these folks are professionals, and their opinions also count when they agree, not just when they disagree.

[WildCat]

About a minute away from launch now. I hope all goes well.

[Dr Adequate]

I'll relax in two minutes when they turn off the engines.

[WildCat]

Looks like everything went smoothly. Rendezvous w/ the ISS tomorrow.

They're now saying they may extend the mission to 13 days.

[R.Mackey]

NASA engineer here... though I don't work on Shuttle, and speaking solely my own unofficial positions. All standard disclaimers apply.

Basic reason the Shuttle is designed the way it is -- it's a very complex spacecraft -- is because the intent, back in 1969 when it was designed, was to boost and return large payloads, and to provide a platform for astronauts to bolt things together in space.

Two realities of engineering have emerged since that time that make the shuttle's original mission much less attractive. The first is the incredible advance of miniature electronics and computers. Spacecraft are now basically disposable. The only "return" missions are things like the Solar Max, a floating materials laboratory flown many years ago; and the only "serviced" spacecraft are Hubble and the Space Station. More recent return missions return on their own, robotically (e.g. Stardust), made possible because they are so much smaller.

The second is a consequence of the first -- electronics, small size, lower spacecraft cost, and advances in robotics make assembly by astronauts unneccessary, and expensive. Think about it: An astronaut, with a wrench, is the single most expensive labor you can possibly buy in the history of mankind. Design against it wherever possible.

We're still flying Shuttle because NASA hasn't designed and implemented a human-rated launch vehicle in over 30 years. NASA has become, largely, a service organization dedicated to sustaining the Shuttle and Space Station programs. Griffin, to his credit, realizes that NASA must change, but he is heavily constrained in terms of what he can and cannot do. He is not allowed to simply fire half of the NASA workforce and send the remaining Orbiters to the Smithsonian, even if that might be beneficial in the long run.

As far as Rutan and Scaled Composites go, I've met and like Rutan and I'm a big fan of what he's doing. But you are not likely to see a NASA-funded prototype go his way anytime soon. NASA can barely afford its current effort to design Constellation. There's no way it can further dilute its limited R&D money with a smaller, limited capability research vehicle that doesn't directly address a written Presidential need.

Rutan's bird has some unsolved bugs, by the way, in particular attitude control. No surprises (X-16 had the same gremlins), and no slam against Rutan; this is the kind of challenge that happens when you aim high. Rutan also knows that NASA will not bail him out, and has taken the more daring path, trying to make it commercially viable. I admire him and his accomplishments.

The current Shuttle mission, and its problems, are really a mixed blessing. On one hand, it exposes many of the problems in the Agency. But on the other, back in the Challenger days, we might never have heard about these problems at all. Let us not forget that spaceflight is a hazardous enterprise. It's a shame that NASA gets hammered every time something happens. Do people freak out every time Jeff Gordon smacks into the wall? It happens.

NASA is, in my opinion, unfairly pressured -- mostly by politicians -- about physical realities that we simply have to deal with. NASA is also quite fairly pressured about how it has responded to some of its problems. We need to keep everything absolutely above board, with respect to risk, cost, hazards to astronauts. The truth is not always attractive, but ultimately as scientists and explorers, the truth is our first and best goal.

I wish only the best for Discovery's astronauts, who are risking everything to do the best job they can. Truly they represent the best of America.

[Belz...]

No kidding. Popular Science had a way better design.

As stupid as that sounds, its true. The old junk has to go.

Well, I assume NASA has gotten budget cuts in the last few decades that might explain why they still use the old stuff. Kinda like the Canadian military and its falling helicopters...

[Kopji]

NASA engineer here... though I don't work on Shuttle, and speaking solely my own unofficial positions. All standard disclaimers apply.
-snip-
I wish only the best for Discovery's astronauts, who are risking everything to do the best job they can. Truly they represent the best of America.

Thanks, that was well written.

[AWPrime]

I will be stunned if the Space shuttle is still used in 2020.

[gumboot]

I will be stunned if the Space shuttle is still used in 2020.

2010 is the shuttle fleet retirement date isn't it?

-Andrew

[richardm]

2010 is the shuttle fleet retirement date isn't it?


They're going to have to get their skates on if they want a replacement by then, I reckon.

[geni]

They're going to have to get their skates on if they want a replacement by then, I reckon.

depends on what exactly is wanted for a replacement.

[AWPrime]

2010 is the shuttle fleet retirement date isn't it?

-Andrew
Some things just won't die.

[AWPrime]

The big question for us Europeans is: Will the shuttle transport the remaining ISS parts?

[Cylinder]

The big question for us Europeans is: Will the shuttle transport the remaining ISS parts?

Yes. The remaining SST missions are tasked with fulfilling NASA's ISS commitment - with a possible HST service mission as the schedule allows.

[Cylinder]

Here (http://www.popularmechanics.com/blog/science/3259521.html) is an article from Popular Mechanics that explains some history of the probability estimates during this and other SST missions.

NASA’s official overall probability risk assessment number (PRAN) for complete loss of life and vehicle for the Space Shuttle remains at the widely quoted 1/100. Theoretically, there’s a one percent chance of catastrophe. While the agency stresses that Space Shuttle flights are extremely dangerous missions—sending humans into space always is—officials worry that the risk has been overstated. According to NASA, in practice, it’s not as bad as it sounds.

“This one in one-hundred is the probability risk assessment number given,” NASA space operations spokesman Allard Beutel tells PM. “It’s the chance of the possibility of loosing the space shuttle and crew.” It’s not, however, the odds of losing the crew on any given mission. “It doesn’t mean that if you have a hundred launches, you’re going to have an accident,” says Beutel.

Karl Sigman, a Columbia University engineering professor, explains the difference: “If you flip a coin, you have a 50 percent chance of getting heads,” he tells PM. “But on your next flip, you’re not going to get tails simply because the other option already occurred.” For odds to make sense, says Sigman, it must be considered over a large number of tries. The larger the number flips, the more accurate the coin flip probability becomes. According to Sigman, the 1/100 chance of a catastrophe would only apply after a large number of launches. It’s called the Law of Large Numbers: The more frequent an event, the more likely you are to see the pattern.

There are thousands of data points that go into calculating the PRAN and there are PRANs calculated for a multitude of different shuttle components. And, while 1/100 sounds extraordinarily dangerous, NASA has launched with worse: A 1993 study of the Shuttle put the PRA number at 1/90. After the Challenger accident, the assessment hit its all-time riskiest 1988, when PRAN for loss of vehicle and crew was assessed at 1/78. Safety improvements have improved probability of catastrophe, but only based on the data available at the time. In 2003, Space Shuttle Columbia launched with a 1/254 PRAN; only after the orbiter broke up during re-entry did engineers realistically factor the risk of foam damage into their PRAN studies. Accordingly, last year, Discovery launched with a 1/123 PRAN, and the huge amount data gathered from that mission has further refined that estimate to the current 1/100—which is, oddly enough, equivalent to the annual voluntary risk associated with a career as a professional stuntman, according to 2001 study.

Apparently the worst-case scenario assessment is called the PRAN - a term I was not familiar with - though planning document also cite LOM, LOV and LOC probabilities as well.