Image of Columbia from Air Force. Photo: NASA TV
Posted on 02/07/2003 4:08:42 PM PST by Lokibob
Image of Columbia from Air Force. Photo: NASA TV |
According to sources close to the investigation, the images, under analysis at the Johnson Space Center in Houston, show a jagged edge on the left inboard wing structure near where the wing begins to intersect the fuselage. They also show the orbiter's right aft yaw thrusters firing, trying to correct the vehicle's attitude that was being adversely affected by the left wing damage. Columbia's fuselage and right wing appear normal. Unlike the damaged and jagged left wing section, the right wing appears smooth along its entire length. The imagery is consistent with telemetry.
The ragged edge on the left leading edge, indicates that either a small structural breach -- such as a crack -- occurred, allowing the 2,500F reentry heating to erode additional structure there, or that a small portion of the leading edge fell off at that location.
Either way, the damage affected the vehicle's flying qualities as well as allowed hot gases to flow into critical wing structure -- a fatal combination.
It is possible, but yet not confirmed, that the impact of foam debris from the shuttle's external tank during launch could have played a role in damage to the wing leading edge, where the deformity appears in USAF imagery.
If that is confirmed by the independent investigation team, it would mean that, contrary to initial shuttle program analysis, the tank debris event at launch played a key role in the root cause of the accident.
Another key factor is that the leading edge of the shuttle wing where the jagged shape was photographed transitions from black thermal protection tiles to a much different mechanical system made of reinforced carbon-carbon material that is bolted on, rather than glued on as the tiles are.
This means that in addition to the possible failure of black tile at the point where the wing joins the fuselage, a failure involving the attachment mechanisms for the leading edge sections could also be a factor, either related or not to the debris impact. The actual front structure of a shuttle wing is flat. To provide aerodynamic shape and heat protection, each wing is fitted with 22 U-shaped reinforced carbon-carbon (RCC) leading-edge structures. The carbon material in the leading edge, as well as the orbiter nose cap, is designed to protect the shuttle from temperatures above 2,300F during reentry. Any breach of this leading-edge material would have catastrophic consequences.
The U-shaped RCC sections are attached to the wing "with a series of floating joints to reduce loading on the panels due to wing deflections," according to Boeing data on the attachment mechanism.
"The [critical heat protection] seal between each wing leading-edge panel is referred to as a 'tee' seal," according to Boeing, and are also made of a carbon material.
The tee seals allow lateral motion and thermal expansion differences between the carbon sections and sections of the orbiter wing that remain much cooler during reentry.
In addition to debris impact issues, investigators will likely examine whether any structural bending between the cooler wing structure and the more-than-2,000F leading edge sections could have played a role in the accident. There is insulation packed between the cooler wing structure and the bowl-shaped cavity formed by the carbon leading-edge sections.
The RCC leading-edge structures are bolted to the wing using Inconel fittings that attach to aluminum flanges on the front of the wing.
The initial NASA Mission Management Team (MMT) assessment of the debris impact made Jan. 18, two days after launch, noted "The strike appears to have occurred on or relatively close to the "wing glove" near the orbiter fuselage.
The term "wing glove" generally refers to the area where the RCC bolt-on material is closest to the fuselage. This is also the general area where USAF imagery shows structural damage.
The second MMT summary analyzing the debris hit was made on Jan. 20 and had no mention of the leading-edge wing glove area. That report was more focused on orbiter black tiles on the vehicle's belly. The third and final summary issued on Jan. 27 discusses the black tiles again, but also specifically says "Damage to the RCC [wing leading edge] should be limited to [its] coating only and have no mission impact." Investigators in Houston are trying to match the location of the debris impact with the jagged edge shown in the Air Force imagery.
Columbia reentry accident investigators are also trying to determine if, as in the case of the case of Challenger's accident 17 years ago, an undesirable materials characteristic noted on previous flights -- in this case the STS-112 separation of external tank insulation foam debris -- was misjudged by engineers as to its potential for harm, possibly by using analytical tools and information inadequate to truly identify and quantify the threat to the shuttle. As of late last week, NASA strongly asserted this was not the case, but intense analysis on that possibility continues.
The shuttle is now grounded indefinitely and the impact on major crew resupply and assembly flights to the International Space Station remain under intense review.
Killed in the accident were STS-107 Mission Commander USAF Col. Rick Husband; copilot Navy Cdr. William McCool; flight engineer, Kalpana Chawla; payload commander, USAF Lt. Col. Michael Anderson; mission specialist physician astronauts Navy Capt. Laurel Clark and Navy Capt. David Brown and Israeli Air Force Col. Ilan Ramon.
"We continue to recover crew remains and we are handling that process with the utmost care, the utmost respect and dignity," said Ronald Dittemore, shuttle program manager.
No matter what the investigations show, there are no apparent credible crew survival options for the failure Columbia experienced. With the ISS out of reach in a far different orbit, there were no credible rescue options if even if wing damage had been apparent before reentry -- which it was not.
If, in the midst of its 16-day flight, wing damage had been found to be dire, the only potential -- but still unlikely -- option would have been the formulation over several days by Mission Control of a profile that could have, perhaps, reduced heating on the damaged wing at the expense of the other wing for an unguided reentry, with scant hope the vehicle would remain controllable to about 40,000 ft., allowing for crew bailout over an ocean.
Reentry is a starkly unforgiving environment where three out of the four fatal manned space flight accidents over the last 35 years have occurred.
These include the Soyuz 1 reentry accident that killed cosmonaut Vladimir Komarov in 1967 and the 1971 Soyuz 11 reentry accident that killed three cosmonauts returning after the first long-duration stay on the Salyut 1 space station.
The only fatal launch accident has been Challenger in 1986, although Apollo astronauts Gus Grissom, Ed White and Roger Chaffee were killed when fire developed in their spacecraft during a launch pad test not involving launch.
No other accident in aviation history has been seen by so many eyewitnesses than the loss of Columbia -- visible in five states.
Telemetry and photographic analysis indicate the breakup of the historic orbiter took place as she slowed from Mach 20-to-18 across California, Nevada, Arizona and New Mexico with the loss of structural integrity 205,000 ft. over north central Texas where most of the debris fell.
The science-driven STS-107 crew was completing 16 days of complex work in their Spacehab Research Double module and were 16 min. from landing at Kennedy when lost. Landing was scheduled for 8:16 a.m. CST.
Abnormal telemetry events in the reentry began at 7:52 a.m. CST as the vehicle was crossing the coast north of San Francisco at 43 mi. alt., about Mach 20.
The orbiter at this time was in a 43-deg. right bank completing its initial bank maneuver to the south for initial energy dissipation and ranging toward the Kennedy runway still nearly 3,000 mi. away.
That initial bank had been as steep as about 80 deg. between Hawaii and the California coast, a normal flight path angle for the early part of the reentry. The abnormal events seen on orbiter telemetry in Houston indicate a slow penetration of reentry heat into the orbiter and damage on the wing, overpowering the flight control system. Key events were:
But the rate of left roll was beginning to overpower the elevons, so the control system fired two 870-lb. thrust right yaw thrusters to help maintain the proper flight path angle. The firing lasted 1.5 sec. and, along with the tire pressure data and elevon data, would have been noted by the pilots.
At about this time, the pilots made a short transmission that was clipped and essentially unintelligible
In Mission Control, astronaut Marine Lt. Col. Charles Hobaugh, the spacecraft communicator on reentry flight director Leroy Cain's team, radioed "Columbia we see your tire pressure [telemetry[ messages and we did not copy your last transmission."
One of the pilots then radioed "Roger," but appeared to be cut off in mid transmission by static. For a moment there was additional static and sounds similar to an open microphone on Columbia but no transmissions from the crew.
All data from the orbiter then stopped and the position plot display in Mission Control froze over Texas, although an additional 30 sec. of poor data may have been captured.
Controllers in Mission Control thought they were experiencing an unusual but non-critical data drop out. But they had also taken notice of the unusual buildup of sensor telemetry in the preceding few minutes.
About 3 min. after all data flow stopped, Hobaugh in mission control began transmitting in the blind to Columbia on the UHF backup radio system. "Columbia, Houston, UHF comm. check" he repeated every 15-30 sec., but to no avail. In central Texas, thousands of people at that moment were observing the orbiter break up at Mach 18.3 and 207,000 ft.
Milt Heflin, Chief of the Flight Director's office said he looked at the frozen data plots. "I and others stared at that for a long time because the tracking ended over Texas. It just stopped. It was was then that I reflected back on what I saw [in Mission Control] with Challenger."
The loss of Challenger occurred 17 years and four days before the loss of Columbia.
"Our landscape has changed," Heflin said. "The space flight business today is going to be much different than yesterday.
"It was different after the Apollo fire, it was different after Challenger."
Columbia, the first winged reusable manned spacecraft first launched in April 1981, was lost on her 28th mission on the 113th shuttle flight.
Did a quick 'histogram equalization' to bring out more detail, both in the positive and negative image. If this is IR, it certainly appears to show a good deal more heat concentrated on the underside of the left wing, compared to the right.
I'll try and post a couple of lunar and planetary/nebula shots. May take a while. LOL!
Nice scope you got there.
Nice scope you got there.
Sweet! I thought about going that route- I have seen some really affordable LX-200s on the used market- but I wanted something that I'd be more inclined to want to regularly schlep around, since building an observatory here isn't really practical. The ETX doesn't have that mighty aperture, but it does break down to where I could lug it on my motorcycle, if necessary.
Maybe we need an astronomy/astrophotography thread at some point. While even Meade admits that the ETX 90 EC isn't a great astrophotography platform, I just found a page where somebody sucessfully jimmied a pc golf-ball webcam onto one! LOL!
Good luck with that. Lots of fun....
My wife and I live in Daytona Beach,Florida.We are the sixth house from the "A-1-A" which puts our location around 1000ft west from the Atlantic Ocean,with KSC around 70-80 miles south.The front of our house faces north,which makes the rear portion of our property face south.The shuttle launches are very visible from my screened in back porch,and if the shuttle goes to the space station,a lot of launches go to the north(passing to our east as it climbs to it's required orbit.The "throttle up" portion and jettison of the solid rocket boosters of those flights are clearly visible from our property.We have a 12" b&w tv on our back porch,and it's antenna picks up WESH-TV News Center 2 NBC affilliate from Orlando with a clear strong signal.We use WESH as our monitor for any shuttle flights.Since we can't see the actual initial portion of the launch,we have the TV on,watch the shuttle "lift off",and then we can get ready to visually watch for it to come into view.We have seen many from our back yard,and my wife even decided to take a "movie" of the January 16th Columbia launch,using our Sony Maciva 91 digital camera ,(that she hand held for the filming of STS-107 until it's eastern trajectory took it from our view). She had only done this filming one other time(since we moved to this location in 1988).The "finished" product of her efforts would probably be in the running for second place in clarity to the USAF photo which we are discussing in this thread,but I am SO glad she made the attempt so we have a memento of Columbia and it's crew's final launch......
OK....sorry for the long intro,but I needed to give you the background for my question to you,and a possible path on which to maybe go to try and find a clue into Columbia's disasterous return to earth...
Your expertise would be greatly appreciated,since from reading your very insightful postings,you might be able to help me with my "theory"...
The reporter( from WESH-TV News Center 2 NBC in Orlando)that covers KSC,is a very knowledgeable gentleman named Dan Billow.His Kennedy Space Center(KSC)"beat",is just about the only thing that seems to be required of him to receive monetary compensation for his labors at WESH.Because of my watching his reporting for so many launches(Space Shuttle and military)I have learned many "little known facts" about space launches,and flight, that I have found very interesting, and due to his "better access" to the higher up KSC personel and property,he is not without fairly intelligent commentary durring any lulls in a pre-launch KSC event.....
While sitting on our back porch at about 10:30am Feb.1st,the b&w tv (tuned to WESH and Dan Billow)was again my monitor,but this time it was kind of a " national grief sharing device" that I was monitoring as I watched and listened......until Dan Billow was brought back on air for another of his many live reports of Feb,1st from his KSC location.....
I have heard "Dan" describe many reasons for a delay or total abort of a shuttle launch such as"the emergency landing site in Spain (or wherever)does not provide the weather needed for a non- orbital abort of a shuttle flight....or a certain tracking station needed for total earth orbit tracking of the shuttle has weather not conducive for launch....or a sensor reading of some kind from the shuttle puts it on the list of "do-not-launch".....except THIS time at 10:30am on Sat.Feb.1st 2003,his very visible,and audible grief had HIS brain spinning and searching for possible reasons for the tragic ending of STS-107 as he asked Orlando for a broadcasted replay of the final moments of radio and monitored contact between Houston and Columbia.....
I watched the replay,and then Dan's KSC reporting continued with the following insite:the wheel wells of the shuttle are VERY well monitored,and as much as is possible, are kept at a constant temperature of around 100 degrees,(forgive me if the temp I gave is wrong...it is the function of it that made me type all this!!!).This is accomplished by actual sensors applying either heating or cooling to the enclosed landing gear-tire area.When the shuttle is in sunlight,the internal temp of the wheel wells will rise...(I think Dan put"as high as 400 degrees??)while in the non-sunlight portion of a shuttle orbit it will cause a decrease in the internal temperature of the enclosed "wheel- well".... ( levels of MINUS 200 degrees could occur??).....
Please forgive me if my actual temps are off,but Dan did say that if the internal temperature was not "controlled",this would result in a constant 400 degree temperature swing(from hot to cold) for each 90 minute orbit of flight.Add the number of orbits that the mission requires of any shuttle flight to bring it to a (hopefully successful) conclusion,(and times that by the # of flown missions)and think about the stress put on all the components inside that compartment(from the tires,hydraullics,metals,fluids etc.that are VITAL to get the shuttle to perform it's "one-shot" chance at a successful landing to complete a mission.This is why the "wheel well" area is WELL monitored,and the temperature of it's contents thermostatically kept at a steady,and as safe a temperature as possible to provide as much protection and stress relief for it's vital contents...
From listening to the final moments of STS-107,it appears that it was a concern to the Columbia crew also.The 16 day flight and it's many orbits put that whole ship through a pretty good workout,not even including Columbia's having to use external fuel tanks from a flight more than 2 years or so prior to their employment on STS-107...(which also means that the newly developed "envirormentally friendly" fuel tank coverings were at least 3 years old when they were finally used.THIS freeper would like to know what makes the covering more "environmentally friendly"....is it because of it's materials are more "envirornmentally friendly",(i.e....no asbestos,etc,)or instead of the coating being made of whatever is nessessary to insure as much safety as can be obtained for the brave (and a lot of times very "taken-4-granted")patriot men and women who do this "job"???....OR were they changed so they "decompose" at a fairly rapid rate,like some consumption containers are chemically manufactured today to decompose(when exposed to extended periods of air,water,sunlight etc) within a much shorter time frame in wherever the items final "resting place" happens to be..(i.e.,a landfill,the ocean,etc...)????.....Since they weren't used for around 3 years AFTER they were manufacured,(and were probably one of the first working examples of this "new" version of covering),and then sat on the launch pad for 3 WEEKS with all the wierd weather swings our area went through durring that period....(along with possibly retaining some of the very substantial rain we had that would turn to ice from the chemical mixture provided to the shuttle for it's fuel to be able to launch).....
OK...(and again,sorry for the long post but here's my question that I hope you can answer for me......).
When the shuttle is in pre-launch monitored mode,and in the monitored initial period of launch,is the "wheel-well" area monitoring data also being scrutinized AND records kept for each shuttle launch?
IF it is,could the data collected of the temperature,( and the readings of other sensors vital to that area) be compared to previous Columbia flights to see what the average readings were ,and then to search for "non-matching" abnormal readings immediately after the"chunks-of-whatever" hit Columbia's left wing,comparing the data until the time of last chance for a non-orbit abort had passed for STS-107???....(and a side question...who's repsonsibility is it to give the call for a non-orbit abort of a shuttle mission????.....)
Would abnormal readings for the "wheel-well" area during that time frame,(being it's temperature is adjusted at ALL times to maintain a safety temperature level)and during the remainder of the flight, possibly give clues to if that area's readings indicate higher "activity" to keep the area at whatever temperature is required?....(kinda like having to maintain the thermostat reading in your house with a door,or a couple of windows open,which means the unit has to run longer and harder to achieve the thermostat settings).
Thanks so much for putting up with my rant....but if it was my "job" to try to solve cause of this thing,.....I would try the theory I have put down here in this post.....Could ya let me know if what I asked you here COULD be checked if comparable flight records were kept????....Thanks again...
You didn't ask me, but it's the same thing that allows the Washington Post and LA Times to 'copyright' all their Government news stories [provided by our bureaucrats paid by taxpayer dollars and disseminated to self-selected messenger-boys] and then sue those same taxpayers who gather freely as Free Republic.
You are right, it is just the co-location of the lines and runs that (a) reacted first and (b) went to band edge before complete breakup.
I was also reacting to the visual note that something heavy came off early and was massive enough to track with the shuttle.
All that said, it may be that tires are up in the wheel high enough to not show the effects of heating quickly, (also the tire pressure sensors may be filtered to react slower, or they may be simply pressure/no pressure sensors that will not react to heating directly. the tires may be strong enough to take quite a bit if increased pressure before blowing. but since you mentioned it, a tire blowing could cause massive damage to weakened structure and may have been the event that caused breakup.
A voice of experience and reason emerges!
Thanks for verifying what others of reason realize. This is a remarkable (and honest) image.
It is amazing how folks with no experience in pushing technology at the cutting edge can state as gospel about hi-tech abilities. Their argument seems to be something like "I can get my PC to capture Donahue pictures from my TV and store them on a disk. If I can do that hi-tech stuff, NASA should be able to do anything!". You would think they have not outgrown the Santa Claus stage of their life.
This elementary statement is one of the best observations I have yet seen about the Columbia accident on this forum. There are similar statements you might have made with subjects of foam/aerodynamics, materials properties/Shuttle environment, photo technology, telemetry, management tasks, etc., but your statement may make drive it into the minds of some of the dunderheads that they are not by themselves going to solve this without far more information, regardless of their no doubt vaunted IQs.
Thank God some level of sanity is coming to these threads! The self agrandising rush to judgement was absurd.
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