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.
Sorry, the 2 separate links about NASA management's terrible decision to enforce a huge loss of NASA's experienced engineering staff, got put together:
http://www.mercurynews.com/mld/mercurynews/5241209.htm?1c
http://www.freerepublic.com/focus/f-news/903020/posts?page=13#13
In aerospace (especially federal aerospace) there is another problem, in that neither civil servants nor commercial managers have a genuine appreciation that -- due to experience -- a 20-year engineer who "costs" 25% more, just might provide better overall "value" than a 10-year engineer. During the last decade federal aerospace orgs have been exuberant in jettisoning seasoned 20+ year engineers for "cheaper" junior engineers who really aren't that much cheaper even in real $, let alone when the "value" equation is considered (which rarely happens).
Example: seasoned aerospace engineers predicted that a well-known interceptor program would have a major problem with flex dynamics (body bending). They were essentially shouted out of the room, and jettisoned from the program, by the juniors who were rushing to fill their shoes. Management essentially supported the juniors in this and muzzled the seniors. The seniors were later proven right (surprise, surprise) but few had survived the cost cutting cycles, and none were ever "thanked" for being right. For what it's worth, I was one of the juniors, who said we should listen to the seniors, but nobody wanted to hear that. That little "cost saving" episode cost the government at minimum hundreds of millions in future "bandaids." But like one of my bosses said later, "it's white collar welfare," so that must make it all OK.
4349-"I was thinking that maybe something simple like a large amount of simple concrete might be good to pour into a large hole in the Thermal Protection System.'
Interesting idea, and this is way out of my area of expertice, we really need a civil engineer, however, I do know that to cure concrete takes several days and the temperatures must be within a certain range. I think, up north in yankee land, they can't pour when it gets too cold, and I KNOW down south it sometimes gets too hot. In fact, when I was working in Saudi Arabia, we had to construct and complete our ICE plant before we completed our concrete batch plant, because we needed to cool the concrete with ice while making it, or else it was no good.
4359 - "I totally agree with your thoughts about the "nothing we could or can do" statement. It is not productive."
I am getting to the point, as screwed up as NASA is, that the politically correct women's lib movement has succeded in screwing it up even more.
And the "can do" attitude has been replaced by the feminist "mothing we can do" attitude.
So, the attitude of "if you don't do something" you will die, of men/military, has been replaced by the "well, since we can't do anything, lay back and enjoy it", attitude of women and rape.
We now have two women in charge, who didn't do anything, 'couldn't' do anything. NASA and a female Army Prison General who also 'couldn't' do anything.
LOL! Ya might just be on to something there.
IMO, the NASA culture did change from can-do to a federal bureaucracy with all the trimmings.(that would include gender equality)
He said the political BS is worse now than it was when it drove me out of there 5 years ago.
Back then, NASA was turning over control of just about everything to USA. Now, the pendulum is swinging the other way, and NASA is taking everything back. They are hiring away a lot of engineers from USA.
As predicted, NASA is trying to shift the blame for their own malfeasance onto the contractors. "They need more oversight" blahblahblah...
My friend is in a fairly high position, and works for a female NASA person who "works hard, but doesn't know anything". How typical. He has to explain the simplest shuttle processing things to her.
Another friend who was one of the most talented managers out there - been there since 1980 - got moved aside for saying the wrong thing to NASA.
The scariest thing he told me was that the Nasa Test Director group - who take over for S0007 (the launch countdown), are all new people. The old "skilled hands" have all moved on. The launch countdowns should be real interesting from now on...<smirk>
My friend had some interesting stories about the recovery effort. He said that during their dragnet in East Texas, they found parts of three bodies that weren't astronauts (via DNA testing). Several old murder cases had to be re-opened.
He also said that the "black boxes" in the Avionics bays mostly survived, but that all the solder on the internal circuit boards had melted so that the chips and other components were piled in the bottom of the heavy aluminum cases.
The one exception was the OEX recorder, which was located under the floor of the mid-deck. They think that maybe the nearby water tanks kept it cool enough to survive the re-entry. What a miracle!
The smart money is on a May launch, although officially they are shooting for February. (There are no launch windows between Feb. and May, thanks to AlGore.)
Thanks for the update. Nothing you have said surprises me, and is no more than I expected.
Except for the part about the additional bodies found in Texas. Interesting, and I hadn't heard this. However, thinking about it, it isn't surprising.
The area where the major debris was found is often pretty, well not remote, but sort of temperate jungle. It's called the 'great piney woods', and is sort of like Brer' Rabbit's hard to traverse Briar Patch in some respect. It has been a hideout and place for run-aways etc since the days of Jean LaFitte, the pirate, the place where runaway slaves went to hide, the place where outnumbered civil war soldiers (from both sides) went to hide when they were running.
It still is thinly populated, and we were very lucky in that respect that it basically landed in this 'scrub', otherwise a lot of people would have been killed.
367 - "The one exception was the OEX recorder, which was located under the floor of the mid-deck. They think that maybe the nearby water tanks kept it cool enough to survive the re-entry. What a miracle! "
Interesting observation, makes sense. And, should tell the engineers/designers something - make a design change and put the really important black boxes in the water/wastewater tanks.
PS - Unfortunatley, It seems like Doc has permanently gone off the deep end. Too bad. I hope he gets better, but (like the whole space program) I have my doubts.
It looks like NASA is well along on the scenario painted by many science-fiction episodes - where there is advanced technology everywhere but nobody knows how it all works anymore.
Oh, the "Foundation" series. Those were great.
I am still lurking when the "moderator" allows me to.
I was disgusted when the moderators here unfairly edited my comments without my approval, then censored some comments which were totally appropriate and within the context of the discussion, and then tried to act like nothing occurred.
As the POTUS says... I will always pick defense of AMERICANS first... and that INCLUDES clearly defining for DUAL CITIZENS that they are not permitted to influence US political life. DUAL citizenship has got to go.
PERIOD.
Excuse me?
Sorry that you feel that Dual citizens belong influencing our national elections...
maybe when you come back to the REAL meaning of US Citizenship, then we'll have a real discussion... but I digress from the longest and most technical thread in this board's history.
I remind you that this thread that heavily impacted by my continuing commitment towards educating the populous on the dynamics in and around our national space program.
Lastly, GOD SPEED THE SPACESHIP ONE...
may be we should start a launch date pool?
I'll take never.
That would be too easy. The few daylight 5-minute launch windows scattered around the calendar are well known within the probram.
Glad to see you back.
Thanks for the kind words...
I still don't trust this board for anything... the editing and the censorship imposed by the illinformed admin is little different than the stupidity printed in the LA Times each day.
Let the people debate!
I'm with you on that. In fact I left FR in disgust for over a month after you were banned.
But I came back, censorship, stupid mod tricks and all.
They can censor me and pull my threads, but I'm not going to donate any more money until this crap stops.
I've been reading about problems/predictions re: Main Landing Gear Door - Thermal Barrier failure and the foam strike.
Does anybody know of some www info showing details or some close-up pictures of what this structure looks like? From what I've seen so far, it looks to me like the tile structure gets a little weird but I can't tell much from what info I have found so far. Thanks..
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