Modified Re-entry?

[Bill Roberts]

I was wondering if anyone knows more about this than I do and can possibly explain. . .

When Ron Dittemore discussed NASA's awareness of possible damage to the left wing of the shuttle, he said 1) that they did not believe the damage was threatening, and 2) that there was nothing that could be done anyway.

Yesterday, in my local newspaper (of all places) I read an Associated Press article explaining how a couple of years ago, when somewhat similar damage was suspected to have occurred to the right wing of Atlantis, the re-entry angle was modified. In short, the suttle was angled slightly to the right so the drag on the damaged wing was reduced (as the article said, imagine a football player turning away from a tackler so his injured knee isn't hit). I believe the process is called "thermal conditioning."

Here is the URL to the story: http://archive.columbiatribune.com/2...208News019.asp

Unfortunately, the diagrams are not included, but the article contains a more detailed description of the maneuver. I've tried to find other stories on this, but my local paper is the only place that I have found anything more than a passing reference to this story.

I'm not attempting to be a conspiracy nut or point the finger at anyone, but does anyone know why this wasn't considered in Columbia's situtation, given the possiblity of damage to the left wing? Perhaps it was too risky or deemed ineffective?

[David Hall]

I wouldn't be surprised if there were some minor alterations that could be made to alleviate some of the stress on a specific area, but I doubt there's a lot that would have made a huge difference overall.

As for what was said during the interview, that was an off-the-cuff remark, so I wouldn't be surprised if he wasn't aware of all the possibilities.

[Kizarvexis]

There is the possiblity that after inspecting Atlantis on the ground that the 'favoring' of one wing over the other didn't make much of a difference. I would like an official explanation of why it wasn't used on Columbia though.

Kizarvexis

[David Hall]

Also, taking the load off of one area would mean increasing the load on others. Maybe the trade-off just wasn't safe in this case.

[Donnie B.]

Keep in mind that NASA's review of the foam incident concluded that there was no chance of significant damage. Therefore there was no need for special measures on reentry.

It's still uncertain whether that conclusion was or was not correct.

[Bill Roberts]

You all make very good points, it's very possible that given what they knew at the time, it didn't seem like the risk was warranted.

My real concern is that NASA is making an effort to be more open about what happened here than they were with Challenger, which is good, but they have created an appearance in this case of not being forthcoming. I wish that they had been more open about the fact that this possibility (favoring the left side on re-entry) existed, but was ruled out; rather than simply saying that even if there was something wrong there was nothing they could do.

I think they HAVE to be totally forthcoming in order to prevent the investigation from becoming more of a political football than an actual problem solving effort.

[Argos]

I think this accident shows that the safety of people on the ground must come into discussion.

To land on Florida the shuttle has to fly over thousands of miles of land. LA, Phoenix, New Orleans, and even Dallas and Houston, were at risk in the last Columbia flight.

I believe it would be a good idea to work on this problem. Spain, a place reserved for an emergency landing should be explored as a permanent site for landing of shuttle missions, at least for those ones connected to ISS, an international project. To land in Spain, the shuttle would approach in the final leg flying over the sea. At the critical phase of reentry it would be over the Atlantic. The risk of casualties on the ground due to accidents on reentry maneuvers would be reduced to a minimum. The downside is the extra amount of fuel required to alter the orbit inclination by some degrees, and the costs of transporting the shuttle back to the US.

Anyway, Florida has shown to be the worst place for a shuttle landing.

[kucharek]

If you don't want the re-entry and approach over country, just always land at Edwards. Then most of the critical stuff happens over the pacific ocean.
But then, in case of an accident, not very much evidence would be salvaged. And, as the current accident proofed, the chances to be hit on the ground are pretty small, even in denser populated area.
Some ten years ago, two Canadian F-18 fighters crashed into each other over Karlsruhe, the 270000 inhabitants city where I live. Debris rained down all over the city (some impact sites within view of my flat). Roofs and cars were damaged, but no one was directly hit by the debris. There are also plane crashes from time to time, but rarely people on the ground are affected.

Harald

[Irishman]

One possible difference is alluded to in that article. The location of tile damage on Atlantis was described as the top of the wing just in front of the elevon. The damage on Columbia was suspected along the bottom of the leading edge.

"You can yaw the vehicle to the side, you can roll the vehicle a little bit," said Steven Schneider, an associate professor at Purdue University’s Aerospace Sciences Laboratory. He said some shuttle surfaces, such as near the fuselage or the back edges of the wings, could be better shielded during such maneuvers than others. "You can’t change the trajectory too much."

Bolding mine.

[Kaptain K]

If Columbia had been headed for Edwards, we would have even less evedence than we do now (Scant and inconclusive as it is.).

[Argos]

Of all the landing sites currently availble, Iberic peninsula is the one with lesser area of dry land to fly over.

I would prefer a single tax-payer protected from falling debris, than a neat investigation.

[DaveC]

On 2003-02-10 11:31, Argos wrote:
Of all the landing sites currently availble, Iberic peninsula is the one with lesser area of dry land to fly over.

I would prefer a single tax-payer protected from falling debris, than a neat investigation.

Ah - taxpayers are a dime a dozen! If the investigation is compromised by inaccessibility of the wreckage, how would it be possible to ensure that future astronauts (and taxpayers) aren't at risk because of a failure that wasn't identified?

[Argos]

On 2003-02-10 11:41, DaveC wrote:

On 2003-02-10 11:31, Argos wrote:
Of all the landing sites currently availble, Iberic peninsula is the one with lesser area of dry land to fly over.

I would prefer a single tax-payer protected from falling debris, than a neat investigation.

Ah - taxpayers are a dime a dozen! If the investigation is compromised by inaccessibility of the wreckage, how would it be possible to ensure that future astronauts (and taxpayers) aren't at risk because of a failure that wasn't identified?

It is a false dilemma. Astronauts know the riks of the enterprise (no pun).

The responsibility of NASA (as anyone else) is to operate without threatening civilians. If thereīs room for cutting the overall risk for the external public, NASA (as any other entity) must act accordingly.

[logicboy]

Here is an IDEA!!

What about using one of our ground based telescopes to inspect the shuttle before re-entry.
They could make the tiles reflect light therefore making them easier to see.

Maybe even go as far as putting small transmitters on each of the tiles. I realize it might be $$$ but to save lives?

[Doodler]

On 2003-02-10 11:31, Argos wrote:
Of all the landing sites currently availble, Iberic peninsula is the one with lesser area of dry land to fly over.

I would prefer a single tax-payer protected from falling debris, than a neat investigation.

*sigh* I was wondering when a NIMBYist would show up. God forbid a taxpayer in another country suffers, eh? Better yet, who cares what really happened, we can just dump the wreckage in the ocean and wash our hands of it. Very selfish... The shuttle is an American bird, she has every right to land here. Any crash in another country opens the doors to all kind of political crap, and fights over salvage of debris, think of the looting happening now in Texas being fought in the international courts. If it has to go down, better it go down on the home field, at least then we retain control of the situation from launch to landing.

[DaveC]

On 2003-02-10 11:54, Argos wrote:
[The responsibility of NASA (as anyone else) is to operate without threatening civilians. If thereīs room for cutting the overall risk for the external public, NASA (as any other entity) must act accordingly.

There will always be some risk to innocent bystanders. For this one incident, using Spain as a landing site would have dropped virtually all the wreckage in the Atlantic Ocean. But if the loss of integrity of the spacecraft had happened at a different point in its landing approach, or indeed while it was still in orbit, the choice of planned landing site may have made no difference to where the wreckage came to Earth. Overshooting the mark in the Iberian Peninsula could drop the shuttle on some pretty populated parts of southern Europe. That may be just as much of an issue as coming up short depending on the type of failure. There just isn't a zero risk option for the Earthbound, although the risk is obviously much less than it is for the astronauts.

[nebularain]

On 2003-02-10 11:57, logicboy wrote:
What about using one of our ground based telescopes to inspect the shuttle before re-entry.

I'm not sure this would have made a difference. From what I heard (and I could be wrong), it sounds as if it was the underside that was possibly damaged. When the shuttle is in orbit, it travels upside-down; therefore, the the underside would have been facing away from the Earth. Once the shuttle flips over for re-entry, I do not think there would be enough time for an inspection.

[logicboy]

I'm not sure this would have made a difference. From what I heard (and I could be wrong), it sounds as if it was the underside that was possibly damaged. When the shuttle is in orbit, it travels upside-down; therefore, the the underside would have been facing away from the Earth. Once the shuttle flips over for re-entry, I do not think there would be enough time for an inspection.

You are probably right about the not enough time issue. I think it would be justifiable to make time for a pre re-entry inspection.

The only thing they would need would be a high resolution image of the underside.

There are many things NASA could do but I feel a change needs to be made to their re-entry procedures.

[Argos]

On 2003-02-10 11:59, Doodler wrote:

*sigh* I was wondering when a NIMBYist would show up.

NIMBYist. What is it? Do I look like one? [img]/phpBB/images/smiles/icon_smile.gif[/img]. Sighing is a common reaction of who encounters a silly argument. Do you regard my concern for (American) civilians as silly, or futile? Well, maybe Iīm too heart-bleeding...

God forbid a taxpayer in another country suffers, eh? Better yet, who cares what really happened, we can just dump the wreckage in the ocean and wash our hands of it. Very selfish...

Iīm not a selfish. Iīm talking from a universal point of vantage. I think iīm expressing a very reasonable concern. As you know, ISS is an international project(*) suject to an international agreement. The spanish "tax-payer" is part of the process. The burden should be equally distributed. And no matter where the "tax-payer" or human being lives. The risks must be reduced at any cost. Spain should be less risky for everyone.

The shuttle is an American bird, she has every right to land here.

NO discussion, sir. I hope the worst case scenario I consider never turns into fact.

(*) I just donīt know if Spain is part of the deal.



<font size=-1>[ This Message was edited by: Argos on 2003-02-10 15:12 ]</font>

[Bill Roberts]

Regarding the risk of falling debris. We're overflown by all manner of aircraft all of the time, craft flying at much lower altitudes with much less time for debris to disperse and break into smaller pieces. Remember, when Pan-Am 103 was bombed, people on the ground were killed too, as with the crash in NYC shortly after the WTC attacks.

Compare the prevalence of jumbo commercial jets and other civilian flights to the relative rarity of shuttle overflights. Even though the Shuttle is more likely to have a problem than other aircraft (unless Courtney Love is on board the other aircraft), the sparsity of overflights adds little to what people have going on over their heads everyday.

[Doodler]

On 2003-02-10 15:10, Argos wrote:

On 2003-02-10 11:59, Doodler wrote:

*sigh* I was wondering when a NIMBYist would show up.

NIMBYist. What is it? Do I look like one? [img]/phpBB/images/smiles/icon_smile.gif[/img]. Sighing is a common reaction of who encounters a silly argument. Do you regard my concern for (American) civilians as silly, or futile? Well, maybe Iīm too heart-bleeding...

God forbid a taxpayer in another country suffers, eh? Better yet, who cares what really happened, we can just dump the wreckage in the ocean and wash our hands of it. Very selfish...

Iīm not a selfish. Iīm talking from a universal point of vantage. I think iīm expressing a very reasonable concern. As you know, ISS is an international project(*) suject to an international agreement. The spanish "tax-payer" is part of the process. The burden should be equally distributed. And no matter where the "tax-payer" or human being lives. The risks must be reduced at any cost. Spain should be less risky for everyone.

The shuttle is an American bird, she has every right to land here.

NO discussion, sir. I hope the worst case scenario I consider never turns into fact.

(*) I just donīt know if Spain is part of the deal.



<font size=-1>[ This Message was edited by: Argos on 2003-02-10 15:12 ]</font>

NIMBYism - Not In My Back Yard-ism. A form of protest that deems anything that may disrupt the normal flow of events at the home of a said individual should not be imposed at any cost, whether said disruption is beneficial or baneful. eg, anew shopping center in a region which will add a number of jobs and economic growth to an area is proposed and the knee jerk reaction of the community, while liking the idea, does not believe said development should occur anywhere it might impose on their particular patch of dirt. Whether by additional traffic or whatnot.

I was not sighing because I found your point silly, futile maybe, definitely frustrating, but not silly. The Station is international, and Spain's part is through ESA cooperation, if at all. I do not know specifics. The Shuttles, aside from the arm, are purely American in financing and construction (Not sure about components, some COULD be imports), so they are OUR responsibility. Not to say that we ought to fly them exclusively where they can drop debris all over us, better they not drop debris at all, but as we've seen the worst cases do tend to happen from time to time, and we ought to see to it we do our best not to make our shuttle's accidents a problem for others. Sorry if it seemed a personal attack, that was not the intent, its just frustration at the concept in general.


edited to add definition of NIMBYism.

<font size=-1>[ This Message was edited by: Doodler on 2003-02-10 16:57 ]</font>

[daver]

On 2003-02-10 11:57, logicboy wrote:
Here is an IDEA!!

What about using one of our ground based telescopes to inspect the shuttle before re-entry.

They've done something like that in the past (maybe even to Columbia). Maybe it should be made mandatory, although i'm not sure that that would do much good. Maybe the shuttles should be equipped with a flying camera that makes a once-around (although now you have to worry about the camera running into the shuttle and causing the damage it was supposed to detect. And if you bring the camera down with the shuttle, you're landing with several pounds of explosive fuel on board, unless you vent the camera's fuel before docking). Even if you detect damage, you still have the question of what to do about it. Maybe someone can come up with some space-going spackling compound that you can use to fill and cracks or voids. And a mobile platform to stand on while applying it. Maybe it can be done; maybe it could even be done within five years. The question is, is it worth it? How much of a fluke was Columbia?

[Doodler]

There is some development going on with remote flying cameras using compressed nitrogen for propulsion, Space.com has a pretty good article on them at the moment.

<font size=-1>[ This Message was edited by: Doodler on 2003-02-10 17:14 ]</font>

[daver]

On 2003-02-10 17:13, Doodler wrote:
There is some development going on with remote flying cameras using compressed nitrogen for propulsion, Space.com has a pretty good article on them at the moment.

<font size=-1>[ This Message was edited by: Doodler on 2003-02-10 17:14 ]</font>

Good idea; that solves the fuel problem for the camera. Still leaves the other issues.

[Argos]

On 2003-02-10 11:59, Doodler wrote:

NIMBYism - Not In My Back Yard-ism.

Ok. Definitely funny. [img]/phpBB/images/smiles/icon_smile.gif[/img]

The Shuttles, aside from the arm, are purely American in financing and construction (Not sure about components, some COULD be imports), so they are OUR responsibility. Not to say that we ought to fly them exclusively where they can drop debris all over us, better they not drop debris at all, but as we've seen the worst cases do tend to happen from time to time,

I see my reasoning has taken a path different than I wanted. I didnīt mean to hurt susceptibilities. I just put a legitimate thought on the discussion. I think itīs fairly legal.

Iīm not willing to argument for the "internationalization" of the shuttles. I really just wanted to post something about a matter that was hardly commented here: the safety on ground. Maybe Iīm over estimating the dangers (I come from a corporate safety culture), over acting my sensitivity or playing the devilīs advocate. But I think this board can withstand weird, sometimes rather foolish, arguments once in a while.

Regards. [img]/phpBB/images/smiles/icon_smile.gif[/img]

[Kaptain K]

Here is an IDEA!!

What about using one of our ground based telescopes to inspect the shuttle before re-entry.

Have you seen the photo of Columbia taken with the Project Starfire camera? It was taken with a 3.5 meter (150 inch) scope equipped with adaptive optics. This is "state of the art" hi-res imaging by a system specifically designed to photograph satelites in orbit. There is very little detail visible. Astronomical scopes are not capable of "slewing" fast enough to keep up with the Shuttle.

[logicboy]

On 2003-02-10 17:13, Doodler wrote:
There is some development going on with remote flying cameras using compressed nitrogen for propulsion, Space.com has a pretty good article on them at the moment.

<font size=-1>[ This Message was edited by: Doodler on 2003-02-10 17:14 ]</font>

Using sensors on each of the tiles and a remote flying camera sounds like a redundant enough system.

But what if something were to break?

[Doodler]

Honestly, we lose the shuttle. All the repair kits, cameras and robots cannot possibly cover every base. You can reengineer the spacecraft till your heart is content, you can fly every possible approach you can think of, and at some point, things are just going to happen. There was a CNN report that said the odds of a failed shuttle flight were 1/200 on paper; in practice, were about 1/60 give or take the next seven missions. After reading all the threads, reviewing the comments from people who know a LOT more than I ever will, the space shuttle as is, is the best system we can build in reusable spacecraft and its still a crapshoot. There will be incremental improvements in the system as new flaws are found and new materials made available, but the fact is, there is no perfect fix. We do not ask these people to take these risks, they volunteer for it, in VASTER numbers than NASA has slots for. All we can do is make these people fully aware (as if this and Challenger didn't make that CRYSTAL clear)and prepare them to handle the challenge. We're as good as we can get right now, realistically, what more can we do?

[Doodler]

On 2003-02-10 19:14, Argos wrote:

I see my reasoning has taken a path different than I wanted. I didnīt mean to hurt susceptibilities. I just put a legitimate thought on the discussion. I think itīs fairly legal.

Iīm not willing to argument for the "internationalization" of the shuttles. I really just wanted to post something about a matter that was hardly commented here: the safety on ground. Maybe Iīm over estimating the dangers (I come from a corporate safety culture), over acting my sensitivity or playing the devilīs advocate. But I think this board can withstand weird, sometimes rather foolish, arguments once in a while.

Regards. [img]/phpBB/images/smiles/icon_smile.gif[/img]

I understand, my thought is that she's our ship, she's our responsibility, for better or worse.

[logicboy]

On 2003-02-11 11:03, Doodler wrote:
Honestly, we lose the shuttle. All the repair kits, cameras and robots cannot possibly cover every base. You can reengineer the spacecraft till your heart is content, you can fly every possible approach you can think of, and at some point, things are just going to happen. There was a CNN report that said the odds of a failed shuttle flight were 1/200 on paper; in practice, were about 1/60 give or take the next seven missions. After reading all the threads, reviewing the comments from people who know a LOT more than I ever will, the space shuttle as is, is the best system we can build in reusable spacecraft and its still a crapshoot. There will be incremental improvements in the system as new flaws are found and new materials made available, but the fact is, there is no perfect fix. We do not ask these people to take these risks, they volunteer for it, in VASTER numbers than NASA has slots for. All we can do is make these people fully aware (as if this and Challenger didn't make that CRYSTAL clear)and prepare them to handle the challenge. We're as good as we can get right now, realistically, what more can we do?

I agree with you but the purpose of this system would be to check the structure and the titles of the space shuttle so that this kind of accident has a lower chance of happening again. To improve the ratio from 1/200 to 1/201+ is worth the extra $$$ to me and it should be to be to NASA to.

Plus the remote camera system would be able to take some awesome shots and aid in work that has to be done up there.