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.
It is standard procedure when separating from a booster or vehicle, to immediately start an orbit change process to get to a safe distance from the stuff you wish to leave behind. Otherwise it just smacks back into you one orbit later.
That's right. According to the reports I've read, Nasa did not notice the debris coming of the Shuttle and hitting the wing until HOURS after liftoff. The Shuttle was already in orbit when they reviewed a frame by frame recording of the liftoff and discovered the debris that came loose at the 80 second point after launch.
Prior to that review there was never any indication or reason to consider aborting the mission and by then it was too late.
Even if they had seen the insulation "hit" the instant it happened (and it happened so fast it was only visible on the slow-motion "instant replay" later -- someone watching that camera's monitor would have missed it "live"), there's another issue.
It just didn't look that bad at the time. It certainly wouldn't have been the sort of issue that screamed "MUST ABORT!". In fact, even the next day, after they had a discussion about the video, based on all they could see and all they knew from previous flights, they concluded that it didn't look all that serious. It's only in retrospect that it's suddenly looking Really Serious. (And even now it may possibly turn out to be a red herring that had nothing to do with the failure.)
And they *can't* and *shouldn't* abort any time something looks "odd" or a "possible" problem. The abort sequence itself is untested, risky, and may result in the loss of the craft. One thread quoted one of the astronauts saying that in the simulator they managed to land safely in less than half of the abort simulations -- the rest of the time they crashed for being unable to make it back to an appropriate runway.
Aborting is NOT something they should do lightly, or "just in case" something appears out of the ordinary. It should be saved for *undeniable* emergencies during launch, when the danger of proceeding truly outweighs the danger of aborting.
It's like leaping out of a commercial airliner with a parachute. It's not something you do except in the gravest of circumstances -- hearing or seeing "something funny" is not a good enough reason.
A legend in his own mind...
Thanks for posting this. It's enough for me. Kranz is the go-to guy for working out of tough spots. If he says there wasn't much that could be done, that carries a lot of credibility.
I recall in the one book about Apollo 13 that the flight controllers have a process of working through their options. They try to keep as many options as they can and not make decisions that unnecessarily eliminate potentials, "closing out" options, I think they call it.
Fact is, once that bird was up there in orbit, the only options were to leave it there or try to bring it back. The laws of physics dictated that it couldn't get to the ISS (conservation of energy, not enough delta v, different orbital height and inclination), nor could the ISS send its Soyuz to the shuttle (it has retrorockets but little in the way or orbital maneuver capability). NASA could have rushed a shuttle to the pad to bring the Columbia crew back, bypassing normal preparation and safety procedures, and risked losing a second ship or both crews if something went wrong. The Russians sending up a Soyuz? Were they ready to do that? Could the Soyuz dock with the shuttle? How many could the Soyuz bring down? How much resupply could the Soyuz bring up? A Progress module to the shuttle? The Russians had one ready to send to the ISS, which needed it. Could the ISS get by without it? It can attach to the ISS but can it get to or dock with the shuttle?
Seems like the options were limited. Stay up in orbit and die up there, or take a chance on getting back down (assuming they knew there was serious damage). Not the kind of limited options flight controllers prefer.
If NASA would have suspected a problem with re-entry, I am certain that this option would have been attempted.
To be as technical as possible..."Shit Happens!"
Not a lot of people realize this. The mindset seems to be, abort the launch and you'll be okay. That is far from true. It takes guts to call an abort because of the inherent risks associated with that. Controllers in fact are reluctant to call for it precisely because it places the systems in a state where there is little experience and even less margin for error.
There have been previous cases where abort is the seemingly obvious call yet isn't made, going back to the very early days of spaceflight. Some of you may be old enough to recall the aborted launch of Gemini 6. The Titan II engines quit after being ignited and the crew had a couple of seconds to decide whether to pull the ejection handle or not. They knew that blasting themselves out of that capsule while it was still on the ground was not exactly without risk, so they sat tight, and saved their ship and themselves.
The other was on the launch of Apollo 12 when the spacecraft lost electrical power as a result of a lightning strike during ascent. The flight director there was very close to calling a launch abort and getting that crew out of there, but the Saturn V was controlling normally even though the command module (separate systems) had lost power. He knew it was safer to get them up into a stable orbit and figure things out than to try an untested abort procedure and risk the loss of the crew during powered flight.
http://www.freerepublic.com/focus/news/835422/posts?page=270#270
It's our best quality that we are skeptical. We live Reagan's "trust but verify" credo, but sometimes, it's a good thing to be able to balance that skepticism with a common sense, studied approach to the facts, before we dig our heels in to one side or the other of an issue.
Well, let's send you up strapped to the wing on the next shuttle launch so you can do some in-flight maintenance.
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