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4 ways Columbia could have been saved. From NASA's Kennedy Space Center Home Page
NASA's Kennedy Space Center Home Page ^ | 04 February 03 | Mitchel Tighe

Posted on 02/04/2003 9:40:32 PM PST by Mitchel Tighe

I have been pulling my hair out watching both the NASA press conferences and also the stupid reporters questions after the absolute tragedy of the Columbia disaster. They all say there was no way to save the ship... That is Nonsense!!

Remember the Challenger disaster where the launch control director was yelling RTLS RTLS after the explosion at 83 seconds? RTLS stands for Return To Launch Site. If 83 seconds was good enough for Challenger. Why wasn't 80 (or more) seconds good enough for Columbia?

If I can find this, then people at NASA know this. Husband and McCool could have easily executed any of these.

There are 4 types of launch aborts that could have saved Columbia. Here is the URL, scroll about half way down.

http://science.ksc.nasa.gov/shuttle/technology/sts-newsref/mission_profile.html

Look under ABORTS and you will see the following:

ABORTS Selection of an ascent abort mode may become necessary if there is a failure that affects vehicle performance, such as the failure of a space shuttle main engine or an orbital maneuvering system. Other failures requiring early termination of a flight, such as a cabin leak, might require the selection of an abort mode. There are two basic types of ascent abort modes for space shuttle missions: intact aborts and contingency aborts. Intact aborts are designed to provide a safe return of the orbiter to a planned landing site. Contingency aborts are designed to permit flight crew survival following more severe failures when an intact abort is not possible. A contingency abort would generally result in a ditch operation.

There are four types of intact aborts: abort to orbit, abort once around, transatlantic landing and return to launch site.

The ATO mode is designed to allow the vehicle to achieve a temporary orbit that is lower than the nominal orbit. This mode requires less performance and allows time to evaluate problems and then choose either an early deorbit maneuver or an orbital maneuvering system thrusting maneuver to raise the orbit and continue the mission.

The AOA is designed to allow the vehicle to fly once around the Earth and make a normal entry and landing. This mode generally involves two orbital maneuvering system thrusting sequences, with the second sequence being a deorbit maneuver. The entry sequence would be similar to a normal entry.

The TAL mode is designed to permit an intact landing on the other side of the Atlantic Ocean. This mode results in a ballistic trajectory, which does not require an orbital maneuvering system maneuver.

The RTLS mode involves flying downrange to dissipate propellant and then turning around under power to return directly to a landing at or near the launch site.

There is a definite order of preference for the various abort modes. The type of failure and the time of the failure determine which type of abort is selected. In cases where performance loss is the only factor, the preferred modes would be ATO, AOA, TAL and RTLS, in that order. The mode chosen is the highest one that can be completed with the remaining vehicle performance. In the case of some support system failures, such as cabin leaks or vehicle cooling problems, the preferred mode might be the one that will end the mission most quickly. In these cases, TAL or RTLS might be preferable to AOA or ATO. A contingency abort is never chosen if another abort option exists.

The Mission Control Center-Houston is prime for calling these aborts because it has a more precise knowledge of the orbiter's position than the crew can obtain from onboard systems. Before main engine cutoff, Mission Control makes periodic calls to the crew to tell them which abort mode is (or is not) available. If ground communications are lost, the flight crew has onboard methods, such as cue cards, dedicated displays and display information, to determine the current abort region.

Which abort mode is selected depends on the cause and timing of the failure causing the abort and which mode is safest or improves mission success. If the problem is a space shuttle main engine failure, the flight crew and Mission Control Center select the best option available at the time a space shuttle main engine fails.

If the problem is a system failure that jeopardizes the vehicle, the fastest abort mode that results in the earliest vehicle landing is chosen. RTLS and TAL are the quickest options (35 minutes), whereas an AOA requires approximately 90 minutes. Which of these is selected depends on the time of the failure with three good space shuttle main engines.

The flight crew selects the abort mode by positioning an abort mode switch and depressing an abort push button.

RETURN TO LAUNCH SITE OVERVIEW The RTLS abort mode is designed to allow the return of the orbiter, crew, and payload to the launch site, Kennedy Space Center. approximately 25 minutes after lift-off. The RTLS profile is designed to accommodate the loss of thrust from one space shuttle main engine between lift-off and approximately four minutes 20 seconds, at which time not enough main propulsion system propellant remains to return to the launch site. An RTLS can be considered to consist of three stages-a powered stage, during which the space shuttle main engines are still thrusting; an ET separation phase; and the glide phase, during which the orbiter glides to a landing at the Kennedy Space Center. The powered RTLS phase begins with the crew selection of the RTLS abort, which is done after solid rocket booster separation. The crew selects the abort mode by positioning the abort rotary switch to RTLS and depressing the abort push button. The time at which the RTLS is selected depends on the reason for the abort. For example, a three-engine RTLS is selected at the last moment, approximately three minutes 34 seconds into the mission; whereas an RTLS chosen due to an engine out at lift-off is selected at the earliest time, approximately two minutes 20 seconds into the mission (after solid rocket booster separation).

After RTLS is selected, the vehicle continues downrange to dissipate excess main propulsion system propellant. The goal is to leave only enough main propulsion system propellant to be able to turn the vehicle around, fly back towards the Kennedy Space Center.and achieve the proper main engine cutoff conditions so the vehicle can glide to the Kennedy Space Center.after external tank separation. During the downrange phase, a pitch-around maneuver is initiated (the time depends in part on the time of a space shuttle main engine failure) to orient the orbiter/external tank configuration to a heads up attitude, pointing toward the launch site. At this time, the vehicle is still moving away from the launch site, but the space shuttle main engines are now thrusting to null the downrange velocity. In addition, excess orbital maneuvering system and reaction control system propellants are dumped by continuous orbital maneuvering system and reaction control system engine thrustings to improve the orbiter weight and center of gravity for the glide phase and landing.

The vehicle will reach the desired main engine cutoff point with less than 2 percent excess propellant remaining in the external tank. At main engine cutoff minus 20 seconds, a pitch-down maneuver (called powered pitch-down) takes the mated vehicle to the required external tank separation attitude and pitch rate. After main engine cutoff has been commanded, the external tank separation sequence begins, including a reaction control system translation that ensures that the orbiter does not recontact the external tank and that the orbiter has achieved the necessary pitch attitude to begin the glide phase of the RTLS.

After the reaction control system translation maneuver has been completed, the glide phase of the RTLS begins. From then on, the RTLS is handled similarly to a normal entry.

TRANSATLANTIC LANDING ABORT OVERVIEW The TAL abort mode was developed to improve the options available when a space shuttle main engine fails after the last RTLS opportunity but before the first time that an AOA can be accomplished with only two space shuttle main engines or when a major orbiter system failure, for example, a large cabin pressure leak or cooling system failure, occurs after the last RTLS opportunity, making it imperative to land as quickly as possible.

In a TAL abort, the vehicle continues on a ballistic trajectory across the Atlantic Ocean to land at a predetermined runway. Landing occurs approximately 45 minutes after launch. The landing site is selected near the nominal ascent ground track of the orbiter in order to make the most efficient use of space shuttle main engine propellant. The landing site also must have the necessary runway length, weather conditions and U.S. State Department approval. Currently, the three landing sites that have been identified for a due east launch are Moron,, Spain; Dakar, Senegal; and Ben Guerur, Morocco (on the west coast of Africa).

To select the TAL abort mode, the crew must place the abort rotary switch in the TAL/AOA position and depress the abort push button before main engine cutoff. (Depressing it after main engine cutoff selects the AOA abort mode.) The TAL abort mode begins sending commands to steer the vehicle toward the plane of the landing site. It also rolls the vehicle heads up before main engine cutoff and sends commands to begin an orbital maneuvering system propellant dump (by burning the propellants through the orbital maneuvering system engines and the reaction control system engines). This dump is necessary to increase vehicle performance (by decreasing weight), to place the center of gravity in the proper place for vehicle control, and to decrease the vehicle's landing weight.

TAL is handled like a nominal entry.

ABORT TO ORBIT OVERVIEW An ATO is an abort mode used to boost the orbiter to a safe orbital altitude when performance has been lost and it is impossible to reach the planned orbital altitude. If a space shuttle main engine fails in a region that results in a main engine cutoff under speed, the Mission Control Center will determine that an abort mode is necessary and will inform the crew. The orbital maneuvering system engines would be used to place the orbiter in a circular orbit.

ABORT ONCE AROUND OVERVIEW The AOA abort mode is used in cases in which vehicle performance has been lost to such an extent that either it is impossible to achieve a viable orbit or not enough orbital maneuvering system propellant is available to accomplish the orbital maneuvering system thrusting maneuver to place the orbiter on orbit and the deorbit thrusting maneuver. In addition, an AOA is used in cases in which a major systems problem (cabin leak, loss of cooling) makes it necessary to land quickly. In the AOA abort mode, one orbital maneuvering system thrusting sequence is made to adjust the post-main engine cutoff orbit so a second orbital maneuvering system thrusting sequence will result in the vehicle deorbiting and landing at the AOA landing site (White Sands, N.M.; Edwards Air Force Base; or the Kennedy Space Center.. Thus, an AOA results in the orbiter circling the Earth once and landing approximately 90 minutes after lift-off. After the deorbit thrusting sequence has been executed, the flight crew flies to a landing at the planned site much as it would for a nominal entry.


TOPICS: News/Current Events
KEYWORDS: aoa; ato; challenger; columbia; nasa; rtls; tal
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To: ALS
And while I'm on the subject... this posting of join dates on members is about as mature as a fresh pile of cowcrap. You can bet your bottom dollar that whoever does such a thing sure wouldn't like it if they joined up somewhere to contribute and got that kind of treatment. You and your kind aren't doing FR any favors by behaving this way. Maybe you need to go get your own board and see how fast it fills up with you reminding everyone that they just joined.

I believe that you are out of line on this. I posted his join date because it was obvious that he had not read any previous posts on this subject, or even listened to media reports or read a newspaper. It was as though he arrive to this subject as a new born babe, therefore the date posting was valid.

141 posted on 02/05/2003 6:51:33 AM PST by w1andsodidwe (NPR free zone)
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To: TLBSHOW
. . . is this how we welcome people here now?

It's how we screen for trolls. Is Tighe a troll? We'll see how he weathers scrutiny.

142 posted on 02/05/2003 6:55:42 AM PST by Kevin Curry
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To: Kevin Curry
Well, let's send you up strapped to the wing on the next shuttle launch so you can do some in-flight maintenance.

Howz about using high powered telescopes, you know, like the ones that capture pictures over Iraq. Ditz.

143 posted on 02/05/2003 7:11:53 AM PST by Fred Mertz
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To: Fred Mertz
I believe we've seen eveidence presented here in previous threads (which I KNOW you read, so don't plead ignorance) that stated the odds of being able to see damage with a ground-based telescope would require the damage to be extensive... if it was a few tiles, it would not have been easily seen...

bottom line: if the damage was extensive enough to be seen by ground-based telescopes, it was extensive enough that the crew would already have been aware of the damage...
144 posted on 02/05/2003 7:16:54 AM PST by Chad Fairbanks ('I WISH, at some point, that you would address those damned armadillos in your trousers." - JustShe)
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To: ALS
ALS signed up 2002-01-26

Sorry, couldn't resist. Sometimes Freep does get a little rough. This post combines several factors that guarantee a flaming response

1. Thread posted first day signed up
2. Posting of hypothesis that has been thoroughly repudiated multiple times on multiple threads, and in various other media sources within last two days
3. Opens thread with statements that are pretty inflammatory

All in all, I think people have been relatively restrained in their comments. As far as saving Columbia, I haven't seen any options suggested that would have involved less risk than the option tried, particularly when you consider that no one knew how bad the damage was. To save Columbia, you would have to change some parameters from BEFORE the launch. Each of these parameter changes would require other changes in the overall shuttle launch program. A couple of options would have been to include more supplies on shuttle launches allowing a longer sustained orbit (weight issues), tile repair kits (technical issues), slowing down before re-entry (fuel issues), docking ring and fuel for access to space station (fuel, technical and space station won't hold that many people issues), having another shuttle ready to launch for rescue (double cost of each launch).

Space travel is tough and dangerous. If it wasn't every bozo that has a hat would be up there. There are people a lot smarter than me who have dedicated their lives to this program and to understanding space travel. Questions certainly need to be asked, but I don't think you'll find any, "well, just do this and everything will be okay" answers.

145 posted on 02/05/2003 8:18:25 AM PST by Richard Kimball
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To: Mitchel Tighe
BUMP
146 posted on 02/05/2003 8:24:51 AM PST by TLBSHOW (God Speed as Angels trending upward dare to fly Tribute to the Risk Takers)
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To: Mitchel Tighe
nasa warned
plenty about the shuttle

http://search.news.yahoo.com/search/news?p=nasa+warned&c=
147 posted on 02/05/2003 8:31:25 AM PST by TLBSHOW (God Speed as Angels trending upward dare to fly Tribute to the Risk Takers)
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To: Mitchel Tighe
AHAHAHAHAAHHAHAH!!AHHAHAHAHH!

ZOT!

zot alert

148 posted on 02/05/2003 8:31:55 AM PST by JudgemAll
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To: Brett66
Unfortunately the eva suits were also on the ground. The mission was not configured for eva. The cargo bay was full of experiment modules.

AFAIK ... No way in, no way out.

snooker
149 posted on 02/05/2003 8:54:41 AM PST by snooker
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To: snooker
Unfortunately the eva suits were also on the ground.

I guess they truly were doomed. Hindsights 20/20 I guess but it would seem like they would stow at least one suit just in case. I think there's a few things they could rethink in the future that would give them more flexibility for dealing with such situations in the future. It's really kind of surprising just how limited their options were.

150 posted on 02/05/2003 9:08:04 AM PST by Brett66
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To: Chad Fairbanks
that stated the odds of being able to see damage with a ground-based telescope would require the damage to be extensive...

Don't put words in my mouth. I didn't use the term ground-based in my statement of query.

151 posted on 02/05/2003 9:43:22 AM PST by Fred Mertz
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To: Brett66
I believe the real problem was the shuttle bay was full of stuff with no door. At least that was what a friend who works close to the shuttle program said to me.

No need for EVA suits if there was no door. No docking collar no way to connect to another mission vehicle. They did each have inside the vehicle suits.

The mission was simply not designed for anything but inside vehicle low gravity experiments.

Doomed from the getgo if the debris actually damaged the wing. IMHO taking out one critical tile near or on the leading edge and there would be no hope for safe re-entry. Since NASA could not prove damage they went with re-entry.

Space is a risky business even if no one is paying attention.

BTW, I was involved with the Apollo program, hence contacts and interest on my part.

snooker

152 posted on 02/05/2003 9:52:35 AM PST by snooker
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To: Fred Mertz
Well, other than Hubble (which certainly wouldn't work), where are all of our other telescopes????
153 posted on 02/05/2003 9:57:54 AM PST by Chad Fairbanks ('I WISH, at some point, that you would address those damned armadillos in your trousers." - JustShe)
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To: Chad Fairbanks
How about our surveillance/spy satellites; you know, the ones that can read newspaper headlines. I'll admit to not having much knowledge about them, that's why I asked the question aloud, hoping someone with better knowledge could address whether some sort of surveillance telescope (satellite, U-2, etc.) could have examined the Columbia from afar.
154 posted on 02/05/2003 10:03:12 AM PST by Fred Mertz
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To: Fred Mertz
So which is it - Sattelites, or telescopes????
155 posted on 02/05/2003 10:04:45 AM PST by Chad Fairbanks ('I WISH, at some point, that you would address those damned armadillos in your trousers." - JustShe)
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To: Fred Mertz
How about our surveillance/spy satellites; you know, the ones that can read newspaper headlines.

Not quite true: the best resolution you're going to get will be about six inches, which means that you can distinguish the PRESENCE of a six-inch square object, not identify what it is.

I'll admit to not having much knowledge about them, that's why I asked the question aloud, hoping someone with better knowledge could address whether some sort of surveillance telescope (satellite, U-2, etc.) could have examined the Columbia from afar.

U-2 is out--the cameras point the wrong way (don't even THINK of trying to roll a U-2 inverted).

Satellites--orbital mechanics may have precluded a detailed examination (you need the satellite, the Shuttle, and the Sun to all be in proper relationship with each other in order to examine the wing in detail.

Additionally, there is the possibility that the object striking the left wing did NOT do significant damage, and that any damage to the tiles was done while in orbit. (IIRC, one of the Shuttles took a window strike on orbit a few years ago--had the same object grazed the underside TPS instead of a window, it would have taken out several tiles, and in all likelihood no one on the Shuttle would have known until reentry.)

156 posted on 02/05/2003 10:13:37 AM PST by Poohbah (Beware the fury of a patient man -- John Dryden)
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To: Poohbah
I really do appreciate your input, Mrknowitall. Thanks very much;^)
157 posted on 02/05/2003 10:18:18 AM PST by Fred Mertz
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To: Mitchel Tighe
Even if it was after the 80 seconds, they still had options.

1. They didn't "have" a problem until the next day. There was no basis on which to call an abort.

2. The Flight Rules governing an abort are very specific, and very limited. They are not based on "something that we won't even know about until tomorrow may have happened (or not)." (Having participated in meetings where these rules were reviewed and revised post-Challenger, I know this to be true.)

3. Aborts are dangerous. The probability of the Shuttle surviving an abort is significantly less than one -- and thus they are (again) not something to do on the basis of "bad feelings." In any case that does not involve serious propulsion or guidance problems, orbit is the safest place to go.

158 posted on 02/05/2003 10:25:55 AM PST by r9etb
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To: fatima
Well you must have missed this at #41-- Try Mitch and this was before my new computer (I've not been here in a few years) that had what I thought was my old PW. Of course, my new computer and Outlook do not have it, ergo, I had to register again. Actually, now that I think about it, the last time I was here was impeachment .

So he left out a word or two like "during impeachment" -- big fricking deal--his posts are a lot easier to interpret than yours.

An easy search turned up this MITCH signed up 1998-04-10 -- which could be his old name.

He never said he was banned but that he lost his password to his old account.


That being said, it is frustrating seeing the same questions and theories being posted over and over after being answered and/or debunked/confirmed.
If they would take the time to find and read over the MANY threads already posted with hundreds of replies they would find what they wondering about, or add to already on-going conversations.
159 posted on 02/05/2003 11:31:33 AM PST by CARDINALRULES (8 days 10 hours 30 minutes until pitchers and catchers report)
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To: Mitchel Tighe
I'm sorry, but having watched the stupid questions the reporters are asking NASA, then reading your post, it's a toss-up as to who is more ignorant of the Space Transportation System - you, or the bubble-headed blond from People Magazine.
160 posted on 02/05/2003 12:54:15 PM PST by snopercod
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