Posted on 02/01/2003 5:50:13 PM PST by hope
This does not jive with the telemetry data NASA apparently received ... the FIRST signs of trouble were EXCESSIVE temps recorded in several systems in the left wing. Shortly after acknowledging 'trouble' with these temp readings comms and telemetry were lost.
CONJECTURE about the tail coming off, based on dubious internet video interpretations is, well, next to quackery ...
Right now, that's all we've got.
CONJECTURE about the tail coming off, based on dubious internet video interpretations is, well, next to quackery ...
I'm with you, we really don't know what happened. In sad truth, we may never know. The evidence has been scattered over two states and even if we found every last bit, it still may not answer the question, 'what happened'.
Such is life.
FReegards, FRiend.
Just get a grip, Justa. I reviewed the link that goes to a 9sec video capture from Foxnews at http://www.gibsonridgesoftware.com/shuttle/zoom.mpg. There ain't nothing there, no matter how fancy you think your hardware is.
Why don't you post the specific frame you're talking about as a still image so we can ridicule your astute observation more easily.
I'm confident that when this video is enhanced there will be no doubt. I have a frame frozen here which I refer to. There are others like it of similar or lesser quality. It's quite clear and quite chilling. The tail is clearly visible. It is seperated from the orbiter (still intact) and perpindicular to the field of view. The black rudder markings are even visible on it. My post (#8) pretty much sums up my take. The information is there. The film simply requires study.
QUESTION:From: http://ltp.arc.nasa.gov/space/ask/landing/Space_Shuttle_tile_failure.txtIs the adhesive used to 'glue' the heat tiles to the shuttle surface strong enough that the tiles would never come unglued (or have any tiles ever come off)? And if a tile were to come off during re-entry in a critical place such as underbelly or nose, would the heat penetrate and destroy the shuttle?
ANSWER, from Bob Speece on August 10, 1999:
The adhesive used to bond Space Shuttle tiles is RTV-560.
This RTV is specially processed in that surface preparations, material mix and handling are controlled to yield the optimum product.
The RTV strength is 250 psi (1723.7 N/m2) in shear and 400 psi (2757.9 N/m2) tensile at room temperature.
On STS-2, we had a hypergolic spill that resulted in multiple tiles coming loose at the launch Pad, these were repaired and the Shuttle subsequently launched.
On STS-4, we applied too much waterproofing material to upper surface tiles and tiles came off during the mission.
Our greatest concern with tiles is damage, this is due to their fragility (they are silica glass).
On mission STS-27R, we suffered much tile damage and in the area of the L-band antenna a tile was so severely damaged that the L-band antenna cover was heat-damaged and had to be replaced.
The tile system protects critical areas on the Shuttle such that if a "burn-through" occurs the results could be catastrophic.
We control the design of the Shuttle and ground systems to eliminate or reduce the effects of damaging debris. The Debris team, of which I am a member, performs routine tasks and inspections that work to protect the Shuttle from damaging debris.
This team performs an intense post-launch film review that looks for damage to the vehicle from debris. If damage is known, the Shuttle flight crew can take measures to reduce the effects of this damage, for example, a more benign attitude for reentry that will reduce atmospheric heat effects.
Our most heat critical areas are those protected by black tiles, these offer the greatest protection against high heat and are normally of increased thickness.
The Shuttle system uses both high and low heat protection tiles, flexible reusable surface insulation, and re-enforced carbon-carbon heat shields to protect flight surfaces.
It's not so clear to me.
There is an optical artifact - a "ghost" image of the shuttle itself - clearest when the zoom is at maximum.
As the zoom-in is happening, this artifact moves away from the shuttle, because of the zoom effect. This sort of artifact is common in viewing very bright objects.
Once the zoom-in is complete, he artifact is on a constant position, relative to the shuttle.
As the camera zooms back out, the artifact moves closer to the shuttle.
About the midpoint of the clip, the left side of the shuttle (right side of image) takes on a reddish glow, and then (unfortunately) the zoom-out starts. Then the trail gets longer.
But I see no tail-piece coming off.
The TIMELIME sheds some light on this: STS-107 was scheduled to be overhead in the DFW area at about 8:03 AM CDT.
By 8:00 AM CDT (straight up) NASA had already experienced comm (and telemetry) failure. The craft was already doomed when it reached the DFW area ...
STS-107 had already experienced catastrophic problems for 3 minutes by the time the video was captured by WFAA CH 8 in Dallas.
That's not what you want it to be.
When you zoom a compound lense, the depth of focus drops, which is what you see here.
Sorry guys, I know you think you've got whiz-bang equipment and you see something no other observer or network studio editing crew has seen, but we have, and we know it's not a "very good and clear" shot of the tail, engines or anything. Keep trying.
I'm confident someone else who has video capture software will soon post the frame. Between the clear frames and the tumbling of the 'artifact' throughout much of the video it's a no-brainer -it's the tail.
I'm pretty sure that's a typo. I've never heard anybody from NASA claim they have any way to replace or repair tiles in orbit. Primarily, I would suspect, because the tiles are all unique with individual partnumbers, as they must conform to the skin of the spacecraft, so you couldn't just stock some of them and stick em on with superglue. You'd have to stock all of them, and that would effectively double the weight of the heat shield! Nor is there any NASA equivalent of the 200 MPH NASCAR Duct Tape which can withstand escape velocities of 12,500MPH!
But to your point, I wonder if NASA actually -DID- know how bad it was...if they did, would you advertise this a la Apollo 13? Would you want the crew to stew on it for 16 days? Would NASA management ethically allow a possible shower of debris that could kill hundreds, rather than require re-entry over unpopulated ocean (and hence sacrifice teh crew anyway.) I doubt they knew, but I also doubt they wanted to know.
It's frightening what things folks are "enabled" to see by the internet, even when just a little simple analysis would go a long way.
THERMAL PROTECTION SYSTEMMore, including descriptions of each material type at:The thermal protection system consists of various materials applied externally to the outer structural skin of the orbiter to maintain the skin within acceptable temperatures, primarily during the entry phase of the mission. The orbiter's outer structural skin is constructed primarily of aluminum and graphite epoxy.
During entry, the TPS materials protect the orbiter outer skin from temperatures above 350 F. In addition, they are reusable for 100 missions with refurbishment and maintenance. These materials perform in temperature ranges from minus 250 F in the cold soak of space to entry temperatures that reach nearly 3,000 F. The TPS also sustains the forces induced by deflections of the orbiter airframe as it responds to the various external environments. Because the thermal protection system is installed on the outside of the orbiter skin, it establishes the aerodynamics over the vehicle in addition to acting as the heat sink.
Orbiter interior temperatures also are controlled by internal insulation, heaters and purging techniques in the various phases of the mission.
The TPS is a passive system consisting of materials selected for stability at high temperatures and weight efficiency. These materials are as follows:
1. Reinforced carbon-carbon is used on the wing leading edges; the nose cap, including an area immediately aft of the nose cap on the lower surface (chine panel); and the immediate area around the forward orbiter/external tank structural attachment. RCC protects areas where temperatures exceed 2,300 F during entry.
2. Black high-temperature reusable surface insulation tiles are used in areas on the upper forward fuselage, including around the forward fuselage windows; the entire underside of the vehicle where RCC is not used; portions of the orbital maneuvering system and reaction control system pods; the leading and trailing edges of the vertical stabilizer; wing glove areas; elevon trailing edges; adjacent to the RCC on the upper wing surface; the base heat shield; the interface with wing leading edge RCC; and the upper body flap surface.
The HRSI tiles protect areas where temperatures are below 2,300 F. These tiles have a black surface coating necessary for entry emittance [radiative cooling].
3. Black tiles called fibrous refractory composite insulation were developed later in the thermal protection system program. FRCI tiles replace some of the HRSI tiles in selected areas of the orbiter.
4. Low-temperature reusable surface insulation white tiles are used in selected areas of the forward, mid-, and aft fuselages; vertical tail; upper wing; and OMS/RCS pods.
These tiles protect areas where temperatures are below 1,200 F. These tiles have a white surface coating to provide better thermal characteristics on orbit.
5. After the initial delivery of Columbia from Rockwell International's Palmdale assembly facility, an advanced flexible reusable surface insulation was developed. This material consists of sewn composite quilted fabric insulation batting between two layers of white fabric that are sewn together to form a quilted blanket.
AFRSI was used on Discovery and Atlantis to replace the vast majority of the LRSI tiles. Following its seventh flight, Columbia also was modified to replace most of the LRSI tiles with AFRSI. The AFRSI blankets provide improved producibility and durability, reduced fabrication and installation time and costs, and a weight reduction over that of the LRSI tiles.
The AFRSI blankets protect areas where temperatures are below 1,200 F.
6. White blankets made of coated Nomex felt reusable surface insulation are used on the upper payload bay doors, portions of the midfuselage and aft fuselage sides, portions of the upper wing surface and a portion of the OMS/RCS pods. The FRSI blankets protect areas where temperatures are below 700 F.
7. Additional materials are used in other special areas. These materials are thermal panes for the windows; metal for the forward reaction control system fairings and elevon seal panels on the upper wing to elevon interface; a combination of white- and black-pigmented silica cloth for thermal barriers and gap fillers around operable penetrations, such as main and nose landing gear doors, egress and ingress flight crew side hatch, umbilical doors, elevon cove, forward RCS, RCS thrusters, midfuselage vent doors, payload bay doors, rudder/speed brake, OMS/RCS pods and gaps between TPS tiles in high differential pressure areas; and room-temperature vulcanizing material for the thick aluminum T-0 umbilicals on the sides of the orbiter aft fuselage.
http://science.ksc.nasa.gov/shuttle/technology/sts-newsref/sts_sys.html
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