Posted on 02/04/2003 1:34:19 AM PST by bonesmccoy
In recent days the popular media has been focusing their attention on an impact event during the launch of STS-107. The impact of External Tank insulation and/or ice with the Orbiter during ascent was initially judged by NASA to be unlikely to cause loss of the vehicle. Obviously, loss of the integrity of the orbiter Thermal Protection System occured in some manner. When Freepers posted the reports of these impacts on the site, I initially discounted the hypothesis. Orbiters had sustained multiple impacts in the past. However, the size of the plume in the last photo gives me pause.
I'd like to offer to FR a few observations on the photos.
1. In this image an object approximately 2-3 feet appears to be between the orbiter and the ET.
2. In this image the object appears to have rotated relative to both the camera and the orbiter. The change in image luminosity could also be due to a change in reflected light from the object. Nevertheless, it suggests that the object is tumbling and nearing the orbiter's leading edge.
It occurs to me that one may be able to estimate the size of the object and make an educated guess regarding the possible mass of the object. Using the data in the video, one can calculate the relative velocity of the object to the orbiter wing. Creating a test scenario is then possible. One can manufacture a test article and fire ET insulation at the right velocity to evaluate impact damage on the test article.
OV-101's port wing could be used as a test stand with RCC and tile attached to mimic the OV-102 design.
The color of the object seems inconsistent with ET insulation. One can judge the ET color by looking at the ET in the still frame. The color of the object seems more consistent with ice or ice covered ET insulation. Even when accounting for variant color hue/saturation in the video, the object clearly has a different color characteristic from ET insulation. If it is ice laden insulation, the mass of the object would be significantly different from ET insulation alone. Since the velocity of the object is constant in a comparison equation, estimating the mass of the object becomes paramount to understanding the kinetic energy involved in the impact with the TPS.
3. In this image the debris impact creates a plume. My observation is that if the plume was composed primarily of ET insulation, the plume should have the color characteristics of ET insulation. This plume has a white color.
Unfortunately, ET insulation is orange/brown in color.
In addition, if the relative density of the ET insulation is known, one can quantify the colorimetric properties of the plume to disintegrating ET insulation upon impact.
Using the test article experiment model, engineers should fire at the same velocity an estimated mass of ET insulation (similar to the object seen in the still frame) at the test article. The plume should be measured colorimetrically. By comparing this experimental plume to the photographic evidence from the launch, one may be able to quantify the amount of ET insulation in the photograph above.
4. In this photo, the plume spreads from the aft of the orbiter's port wing. This plume does not appear to be the color of ET insulation. It appears to be white.
This white color could be the color of ice particles at high altitude.
On the other hand, the composition of TPS tiles under the orbiter wings is primarily a low-density silica.
In the photo above, you can see a cross section of orbiter TPS tile. The black color of the tile is merely a coating. The interior of the tile is a white, low-density, silica ceramic.
Cold Heat(formerly wirestripper)
Bet it would have. It always looked like an aluminum beer can just waiting for the superheated air to get inside.
I don't think any actual photo was ever released.
Here's the original SF article and some FR threads (3) , but no photo.
S.F. man's astounding photo
Mysterious purple streak is shown hitting Columbia 7 minutes before it disintegrated
http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2003/02/05/MN192153.DTL
FR Search results for
S.F. man's astounding photo
http://www.freerepublic.com/focus/search?s=S.F.+man%27s+astounding+photo+&ok=Search&q=deep&m=any&o=score&SX=41994bd073c5d9c49cc8e49351eea042194d1686
There is an E-mail link to the reporter. Obviously he never followed up because Bush did it.
Obviously he never followed up because Bush did it.
4 More Beers and I might buy into that theory too. ;-)
sprites do exist, the heliosphere is like a giant tesla bulb.
Maybe "WE" can't handle the 'truth'.
Majestic 12 rules.. :-}
Four more beers. Now that's a platform I can support!
4480 - "Does anybody have a copy of, or link to, the photo taken in San Francisco of the "purple-corkscrew-lightning-bolt" thing? "
I guess I was one of the few who saw it, and actually got a copy. It was very 'wierd'.
However...., almost as soon as I got it, I had a hard drive screw up (why I don't know) and it and some other things disappeared.
So, sorry, I don't have it either, but it was out there, and maybe if you keep searching you will find it, if they didn't bury it too deep.
Note - numbers of 'interesting' photos and links 'disaapeared' off the web about that time. I also 'lost' a very interesting article on Sadaam's weapons of mass destruction, including planes for spraying poison gas, and crop dusters, and rocket distibution vehicles.
LOL! You better buy some tinfoil!:-)
Sorry, I don't have it either.
I got to thinking, and I lost mine as well, about the same time. I blamed it on my crappy Norton AV. I traced it to a virus I picked up on a photo hosting joint that a fellow freeper had some pics on and she sent me one via E-mail.
I now have a very much better scanner, but it really did not explain why my drive crashed.It got goofy and then failed to load.
The virus never had a chance to propagate. It was deleted by the av.
I had to reformat.
IRRC , It seems to me that the particular wierd photo(s) were an anomaly associated with wide aperaturs and long shutter speeds with that particular model of camera, some sort of Nikon, or something to that effect.
4492 - "I now have a very much better scanner, but it really did not explain why my drive crashed.It got goofy and then failed to load.
The virus never had a chance to propagate. It was deleted by the av.
I had to reformat."
Similar to my story as I remember, wierd. I tried to reformat, and couldn't get it to work. I Ended up disposing of the whole drive, and starting over, from scratch, with a brand new drive. Eventually, I got a whole new computer because of the experience.
Bob was only giving you the IIRC of it. I have not seen the pics either, even though we hunted for them, and the fact they are not on the net may be because they were traced to the artifact problem.
Then again, maybe little green men...................................
Oh, never mind.....LOL!
Yes, exactly.
If it were white lightning, it would not have gotten any attention, except to say the ship is resistant to such things.
There was radio comm throughout this period and there are no reports from the ship that indicate any concerns.
I would have thought that ground crews would have some indications as well.
What we do have is visuals of a chunk of foam hitting the leading edge of the wing on takeoff, then a gradual sequential failure event story that emanates from this specific area.
While the source of the interesting visuals from the ground in Cali are interesting, none of them seen to have any connection to the event sequence, except for reports of debris coming off the airframe.
Without a linkage to the colored lightning, or display, it remains as a isolated incident of interest. I don't think seeing the pictures would help at all. Which, is why I have not really been concerned about them. They do not fall into the event sequence in any way that I can see.
Systematic trouble shooting 101.
Something that this "lightning" brings to mind is the electrodynamics of a conductor (the shuttle, RCC carbon) moving thru even a weak magnetic field at 18,000 mph.
Maxwell's V x B can yield some large numbers at 18kmph.
With the energy of tons of fuel converted into a high velocity "semi-" conductor (the shuttle), I think some very bizarre electric-related-stuff could happen to a slightly cracked leading-edge RCC carbon-composite panel.
Does anyone know, when NASA does analysis of the shuttle's re-entry, how do they electrically model the shuttle? As an insulator? A resistor of very low or medium resistance? A network?
4498 - It's been several years now, and I only saw the strange image once, and it was strange, and it wasn't just the color. It was sort of a combination of lightning strike, static electricity, and kirilian photography, but in various densities of purple only, combined with a relatively normal image.
As i said, it was strange. And I have seen some strange photo images, especially in older cameras, for the lense coatings they use wierd metals, to cut lense flare and enhance images, and make all the different lensegrindings fit together. We don't have that trouble much any more, since they have all this computer design, but older cameras did. I had one lense which 'rusted' in between the different layers of glass in the lense. Ruined an expensive lense.
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