all of a sudden, i heard a big explosion. >> a mysterious flaw brings down a boeing 737. >> there's something going on that left no marks, no calling card. >> shortly after takeoff, a powerful explosion rips apart twa flight 800, igniting controversy about what really happened. >> if anybody thinks that this chairman is involved in any kind of cover-up, they're damn wrong. >> conflicting commands put two jets on a collision course. >> descend, descend. >> and the devastation provokes a violent act.

>> it was a crime of almost unimaginable magnitude. >> terrifying crashes and the dramatic investigations. >> the navy's a suspect. >> true to life animations reveal the critical moments that lead to disaster. september 8th, 1994, traveling from chicago, u.s. air flight 427 is flying at 6,000 feet as it prepares to land in pittsburgh. when suddenly the boeing 737 spirals out of control. 28 seconds later it smashes down into a field in hopewell township, pennsylvania. >> there was a real loud motor

that was screaming. all of a sudden i heard a big explosion. >> police officer george david is 2 1/2 miles away from the crash site, which happens to be next to his farm. >> that was when i got the phone call. they said, you better get up here right now. a plane had just crashed. >> when david arrives, it is a horrifying scene. the airplane has been obliterated by the 300-mile-per-hour impact. there is no hope for the 132 passengers and crew on board. >> i've been a policeman for 25 years. i've seen a lot of things, but that was the worst that i've ever seen it. >> investigators will try to find clues among the destruction. it's a daunting task for the ntsb investigator in charge, tom haueter. >> it was first time that an

ntsb team had to wear biohazard suits to go on site. because of the impacted on the level of destruction there were human remains. >> an aviation mains technician captures the scene up close prying a rare and vivid glimpse into the investigation. >> bodies up there. >> there was no airplane left. >> looks like the cockpit up there. >> clearly the airplane hit close to being vertical at a

high rate of speed. >> so you're looking at one of the engines, right engine. looks like the right wing. you can see it's not very far from the tail section. >> pilot john cox, who has extensive background with 737s is assigned to the investigation as a representative for the airline pilots association. >> facing now the direction that the airplane was, it's directly behind us. >> as an aircraft accident investigator, you have to shift into this -- i can't help the people that are here. i now need to understand what happened so we don't have a recurrence. >> several teams worked to identify and recover pieces of the wreckage. >> left engine pickup. you can see parts of clothes. some wires. the stuff here is waiting for

decontamination. before it goes to the hangar. >> at a nearby hangar, the wreckage will be sorted and analyzed piece by piece. >> this is day one of the sorting process. >> the flight data and cockpit voice recorders were ejected from the airplane on impact and are quickly recovered. but they don't provide any clear answers. there are no sounds of explosions and no evidence of a major mechanical failure, but the recorders do provide investigators with a clearer picture of the flight crew's final moments.

one minute before impact, the crew of flight 427 is alerted to another airplane that will be passing below them. >> they're looking for the airplane. first officer acquires it visually and tells the captain, yes, i see the jet stream. and then they encounter the wake turbulence of a delta airlines 727 and not an uncommon event at all. the airplane rocks around and moves. and from that moment of encountering the wake, something happened. they couldn't stop the roll in the airplane. and this was very difficult to listen to as a pilot because i could hear them struggling for control of the airplane and every second that ticked by they were losing that battle. >> as seen in this ntsb video, investigators set up a test flight that would examine the possibility that the u.s. air pilots were startled by the wake of a nearby 727 airplane causing them to lose control. >> what we found was you could take the airplane, let go of the controls and the airplane would come out of the wake and regain its composure and fly on with no problems. there was no reason to lose control of the airplane. >> one of the lead investigators made a very, very good observation.

and that was that if the wake of a 727 could cause the loss of control of a 737, we'd have 737s falling out of the sky weekly or more. >> investigators zero in on flight 427's rotation or yawing toward the left just minutes before the pilots lost control. >> we knew the airplane yawed, and the question was what would cause that. and it quickly became apparent that the only device that could make the airplane yaw the way it did, was the rudder. that's what it's designed for. >> the rudder is positioned at the tail of the boeing 737 and is used by pilots to control the plane's movement to the right

and left. trying to determine how the rudder could have malfunctioned, investigators test every theory they have. >> there were a couple people on the airplane that were very heavy, and one said, well, what would happen if the floor gave way and a passenger stepped on a control cable? could that have done it? >> so we did a test, and that quickly became obvious that that event couldn't happen. that the amount of weight required was too great. so we looked at all kinds of bizarre potential failures. you name it. everything was considered. and one by one we eliminated them. >> the safety board could not determine exactly what caused the accident. people started linking u.s. air

427 to flight 585. both airplanes were on approach, both rolled and dove into the ground or unknown reasons. >> the two flights have something else in common. both airplanes are boeing 737s. >> the most widely used jet in the world. the second time something unexpected had happened and resulted in the loss of an airplane. if another one went down, they were going to ground the airplane. and the ramifications for grounding the 737 were unbelievably severe. this sets off a global economic catastrophe. we had to find out what happened. coming up -- another boeing 737 ends up in serious trouble. could that crisis lead to a break in the case? >> so you have two pilots shoving with all their might and all it's doing is driving them back, keeping pushing them back doesn't go forward.

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u.s. air flight 427 smashes down outside of pittsburgh. it is the second boeing 737 in three years to suddenly roll for unknown reasons and then crash killing everyone on board. it's a mystery threatening to ground the most widely used jet in the world. investigators suspect a problem with the rudder, which controls the plane's movement to the left and right, but they find no evidence of a malfunction. nearly two years after the crash, a possible break in the case. the pilot of an eastwind airlines boeing 737 experiences a sudden roll as the jet approaches richmond, virginia. >> he quickly got on the rudder pedals. so you had two pilots shoving with all their might on a rudder pedal and all it's doing is

driving them back. it keeps pushing back at them, it doesn't go forward. we've never had this report from a crew of a pedal back forcing against them. now we're into a different scenario. >> fortunately they were at a higher air speed than the 427 which gave them more control. they were able to successfully land the plane. >> after hearing the pilot's experience with the rudder pedals, investigators suspect a jam might be the problem in the airplane's rudder system. >> the pilots control the rudder on the 737 with pedals. those pedals are connected via cables to the muscle, if you will, that physically moves the rudder. that's the power control unit. and like power steering in your car, it's hydraulically powered. >> about the size of a soda can, the power control unit or pcu, houses a set of valves called the duo servo valve. this causes hydraulic fluid to move the rudder. >> this is the duo servo valve. just by moving back and forth

across these openings it redirects fluid. >> in the days after the u.s. air accident, investigators recovered the flight 427's pcu from the crash site. >> some is intact. some of the brackets broken. >> if something did malfunction inside this pcu, it left no evidence. >> the valves were not badly scarred. there were no marks. there wasn't an instant indication of what would have caused the power control unit to have problems. >> investigators run a battery of tests on the pcus from u.s. air 427 and eastwind airlines, trying to determine if the units can jam. what they find is even more alarming. not only can the pcu jam, but it

can then deflect the rudder in the opposite direction. >> if you jam the secondary valve just slightly off neutral, you could cause the valves to basically misalign and import hydraulic fluid in the wrong direction so the rudder reversed operation. this would be like driving your car and you turn to the left and the car goes right. you'll never figure this out before the car goes off the road. >> investigators had found a lethal malfunction in a valve the size of a pencil capable of bringing down a boeing 737. the malfunction leaves no marks or scars, almost as if it never happened, matching exactly what investigators found in u.s. air 427. >> all of a sudden you put the reversal scenario in and it all started coming together that all these parts now fit. the big puzzle we've had the edges and everything else, now the center pieces are all locking in. >> when flight 427's crew encountered the wake turbulence of a passing airplane, they press down on the rudder pedals to counter the wake and move the airplane slightly to the right.

but the duo servo valve jams and misaligns causing the rudder to be deflected in the opposite direction. >> and what they didn't recognize was that the rudder was full over. so as they're pushing, the rudder's not moving because it's jammed, but they don't know this. >> then the nose starts to follow through and the crew pulls back to bring the nose up and the plane just enters what basically look likes a spin into the ground. >> the pilots of 427 faced a condition they never heard of, they weren't trained for. from a pilot's standpoint, you never consider the possibility that if you turn to the right, the airplane's going to go to the left. they didn't have a long time to sort it out. they had around the 13 seconds to diagnose the problem, deal with it effectively. >> it takes 4 1/2 years, one of

the longest accident investigations in aviation history to solve the mystery of flight 427. with it investigators are able to bring closure to another cold case, united flight 585, the other boeing 737 that crashed three years earlier. >> the rudder system on the 737 fleet has been completely redesigned. it's a very different system now than it was at that time. there was a lot of changes also to flight crew training. more hands-on flying, being ready to recover from unusual upsets and unusual events. >> history's proven us to be right. there's not been another occurrence of a rudder hardover since, and i think we made a good airplane even better. coming up -- one of the most infamous aviation disaster in history. >> it appeared to be a flare going straight up. >> what really happened to twa flight 800? >> microscopic explosive traces of unknown origin have been

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july 17th, 1996. beach goers and boaters are enjoying a summer evening at twilight on long island, new york. nearby, at jfk airport, a boeing 747 is taking off carrying 230 passengers and crew headed for paris. less than a minute later, as twa flight 800 is climbing over the atlantic, there's an explosion. the force rips the airplane apart. other pilots in the area begin reporting what they've seen to air traffic control. >> we just saw an explosion up ahead of us here about 16,000 feet or something like that. it just went down in the water. >> rescue teams scour the area for survivors, but no one is found alive. as dusk turns to dark, all that can be seen of the boeing 747 is

the burning debris and jet fuel on the surface of the water. >> we seen the big flames. we didn't expect to see that. right when we seen that, we knew it was going to be pretty bad. we found our first victim. it was a female. and in bad shape. >> as the wreckage burns, so does speculation that there may have been a bomb on board the plane. >> you have to remember the times. this had been the first attempt at the world trade center. and i think terrorism was just getting on people's radars. >> by morning, eyewitness accounts point to yet another alarming possibility. a missile. >> we saw what appeared to be a

flare going straight up. >> and then we seen this white glowing thing. then a big ball of fire came out of it and two pieces on fire fell into the water. >> the ntsb sends a go team to determine what brought down the plane while the fbi launches a criminal investigation. >> if it is a terrorist event, we then have the challenge to find out who the perpetrators were, who the cowards were that did this. >> from the safety board point of view, we want to know is it possibly just an aviation safety issue we need to know about, so there came two investigation, one for the fbi and one for the ntsb. >> the first challenge for investigators -- recovering the victims and the wreckage submerged more than 150 feet in the atlantic ocean. to do this, investigators employ the resources of the u.s. navy.

it will be one of the largest diver-assisted salvage operations ever conducted. it is both difficult and dangerous. >> i talked to the grapple master diver and he was talking about like it was diving in razor blades. >> as pieces of the wreckage are recovered and examined, investigators find what could be a frightening break in the case. >> microscopic explosive traces of unknown origin have been found. >> even more disturbing, rumors are swirling online that a missile may not have been fired by terrorists but by the u.s. military. the fbi investigates the claims, scrutinizing u.s. naval vessels in the area at the time of the crash, but they find no

evidence. >> i can assure you that we've looked at every angle, every possibility, and the military of this country has had nothing to do with this horrendous tragedy. >> but proponents of the friendly fire theory believe there's been a cover-up. >> the navy's a suspect. >> let's go, come on. >> the navy's a suspect. why they shouldn't be taking part in the investigation. >> if anybody thinks that this chairman, this agency's involved in any kind of cover-up, then they're damn wrong. >> i tried to deal with the distractions so our investigators could deal with doing their work. >> investigators have been recovering as much of twa flight 800 as they can. pulling pieces from the bottom of the ocean and transferring them to a hangar where they will attempt to reconstruct the aircraft. >> to see that massive jumble of wires certainly brought home to me how difficult it's going to be to try to put that all back together again. >> investigators recover hundreds of pieces of the wreckage, an astounding 95% of the airplane. when they finish assembling this massive puzzle, it is the largest aircraft reconstruction in history. >> when an explosive device goes off in close proximity to metal it leaves behind very small craters and localized melting and all kinds of soot patterns and things like that. we were able to determine that

there was absolutely no evidence that a bomb exploded close to the structure and also that there was no evidence that any kind of particle might have penetrated from a missile that exploded nearby. >> looking inside the airplane, we have all the human remains x-rayed looking for particles of explosion that have been captured by the body. all the seat cushion, all the other parts we had examined looking for the evidence of explosion with the shrapnel flying around. we didn't see that, with the evidence we saw coming back. >> as for the traces of explosive residue found, investigators believe it could have been transferred from military ships that transported the wreckage from the crash site. after 16 months, the fbi closes their parallel investigation. >> the team conducted a total and thorough investigation. one, there was no evidence of high explosive damage. two, there was no evidence of explosion of a missile war head, three, there was no evidence of missile impact.

>> if it isn't a criminal act, then what brought down twa flight 800? and how can the eyewitness accounts be explained? coming up -- >> we were all surprised that it didn't take a lot of energy to ignite these vapors. blp brap isn't it beautiful when things just come together?

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july 17th, 1996, twa flight 800 explodes in flames shortly after takeoff. the fbi rules out a bomb or missile, but it will take a four-year investigation, the most costly and extensive in the ntsb's history, to determine the cause. after pulling debris from the ocean, investigators conclude that the airplane broke apart into three distinct sections. >> the front section including the cockpit and the first class areas broke off and that just fell to the ground, then much further away you had the rest of the airplane, which seems odd. it was clear that piece of the airplane had to continue some part of the flight for a lot longer. went back and started looking at all the pieces that came off first. they all came out of areas around the wing center fuel tank. so it started becoming apparent that whatever happened happened inside the wing center fuel tank.

>> unlike gasoline, jet fuel isn't highly flammable. but as this faa test shows, when it's heated, the vapors that are produced can be explosive. as twa flight 800 prepares to take off from new york's jfk airport, the center wing fuel tank, about the size of a two-car garage, is nearly empty. >> all that was in that fuel tank was basically just residual fuel, just a small amount of fuel sloshing around the bottom of the tank. >> given the short duration of this particular flight, the operators don't usually use or put fuel into the center fuel tank because they don't need it. the wings hold a sufficient amount of fuel. >> you can save some money and get better performance by leaving the fuel out of it. >> with passengers waiting on board flight 800, a delay with baggage is keeping the plane at the gate. >> it was a hot day in new york, and they've had the air conditioning packs running to keep the aircraft cool. the air conditioning packs are mounted in close proximity to the center fuel tank. >> as the ac packs work to keep the airplane cool, they're

actually generating heat underneath the center wing fuel tank. >> so the fuel tank was actually getting very warm. so when the airplane takes off, you have this warm fuel vapor. if there was a full load of fuel in that tank, it could absorb that heat with no problem. >> it was generally believed that fuel tank were not really flammable. they couldn't really even be ignited because the temperature wasn't great enough. >> and so we took a 747 tested them in very similar conditions, and we were all surprised how hot it got and also it didn't take a lot of energy to ignite these vapors. it's less than you feel if you rub your feet across a carpet

and touch a door knob and the spark you get. less energy than that was necessary to ignite that fuel tank. >> but there is no clear source of ignition on board twa flight 800. by design, only low voltage wires are used inside the fuel tank. >> however, those low voltage wires pass in very close proximity to much higher voltage wires in wiring bundles. and as the airplane's age and these wiring bundles chafe, you can have occasion where there's arcing or shorting between these wires, which introduce this high voltage into low voltage wire and now you have an ignition source. >> we don't have a piece of wire or something that we can hold up and say, this absolutely did it. there's not enough left. the ntsb believes and i believe it's most likely a short circuit of the wiring and that certainly was very possible. you look at all the evidence.

whatever ignited the fuel of the tank was inside the tank. it didn't come from outside. >> the cockpit voice recorder recovered one week after the crash may provide evidence. the pilot is heard observing a strange reading on a fuel flow gauge. >> that's probably an indication of some type of short circuit going on. this airplane was old, it was getting ready to be taken out of service. >> and there are more clues. one second before the cockpit voice recording ends, there are two dropouts in background noise suggesting a possible arc on the cockpit wiring. investigators believe in this moment high voltage enter the center wing fuel tank igniting the warm fuel vapors. >> that ignition caused overpressurization of the tank that blew out the forward panel of the tank. you can see the indentation where it's very clear on slam down, there's a very clear mark. >> from that position we had fractures that went down into

the fuselage because of the pressurization of the airplane itself. that crack ran around the portion of the lower fuselage. >> that caused the nose of the airplane to detach from the rest of the aircraft. it fell off. if you drop the weight off the front, the center of gravity goes back, the airplane's going to nose up. it's going to climb and go up. engines are still producing thrust. >> the aircraft enters a steep climb, ascending between 2,000 and 3,000 feet. 42 seconds after the initial explosion, the left wing separates, spraying unburned fuel and ignites a second fireball. the wreckage, with passengers inside, plunges to the surface of the ocean. the breakup of flight 800 provides explanation for one of the most confounding aspects of

the investigation -- the eyewitness accounts. many described an ascending streak of light moving to a point of a large fireball that then splits into two. >> the sound happened first, and then the fireball. >> what's really interesting looking at the witness statements was how many witnesses reported they heard the explosion and looked in that direction and saw the fire coming down. now, if you take a look at distance between the speed of light and the speed of sound, it's quite clearly that the explosion happened some time before they heard it. and so when they heard the explosion, that already happened some time ago. and so they turn and look, they're seeing the aftermath. they're seeing the fire after the explosion. they didn't see the initial event itself.

>> investigators believe that the ascending streak of light that eyewitnesses describe is the main fuselage still climbing after the initial explosion despite the ntsb's findings, theories persist of a bomb or missile attack on twa flight 800. >> it is unfortunate that a small number of people pursuing their own agendas have persisted in making unfounded charges of a government cover-up in this investigation. >> i look back, and i am in awe of the cooperation and coordination of the thousands of people that were involved and touched this investigation. that's why i feel so strongly when anyone questions the patriotism or the responsibilities that were exercised by the investigators of twa 800. everyone understood that 230 lives had been lost, and it was up to them to do the very best they could to answer the question why. >> as a result of the ntsb's findings, major safety improvements are implemented with both aircraft design and maintenance.

>> we now have systems in center fuel tanks so that if there is not fuel in them that there's an increased amount of nitrogen, that is nonexplosive, that's manufactured on the airplane and then directed into the fuel tank. aging aircraft wiring maintenance programs have been significantly improved. that's a direct result. >> for the families of the victims, the tragedy leads to the passage of the family assistance act, forever changing how loved ones are treated after transportation disasters. >> families will know exactly where to go and who will speak for the government when they have lost a loved one. >> it took the events of twa 800

and the action of president clinton to ensure that their loved ones were given the proper respect when people have a loss and a tragedy like that. >> coming up -- >> descend, descend. >> two jet liners on a collision course. >> the closure rate is 16 miles a minute. you could not visually avoid the collision. >> and the devastation will spur a deadly act of violence. >> this vigilante approach is an impediment to aviation safety for all of us. yeah. we need to sell it. hi. need an appraisal? yeah. we do. vo: when selling your car, start with a written offer, no strings attached. carmax. start here.

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climb to 36,000 feet as they pass through german airspace. at the same time, bashkirian airlines is en route from moscow to barcelona. the russian tupolev airplane is being used for a school trip. on board mostly children and nine crew member. the flight enters german air space flying at 36,000 feet, the same as the dhl cargo jet. the two airplanes are on a collision course. despite being over germany, the airspace is controlled from zurich by the private swiss air space control company skyguide. air traffic controller peter nielson is the only person handling the airspace at the

time. his colleague has taken a break, leaving him to monitor two screens several feet apart. this is against regulations. but a common practice known and tolerated by skyguide management. on one screen, nielsen is busy coordinating the arrival of a delayed airbus. he doesn't notice that on the other screen, there is a conflict between the russian airplane and the dhl cargo jet. >> the controller was overloaded. had a lot of responsibility. an overloaded controller is more prone to make errors. >> to make matters worse, nielsen doesn't realize the ground-based optical warning system which alerts him to imminent collisions has been switched off for maintenance. in the sky, the two airplanes

are less than a minute from reaching each other when an on board system sounds an alert to both crews. >> traffic, traffic. >> the traffic collision and avoidance system, or tcas, is one of the great technological innovations in airplane safety. it provides the crew not only with a display of potential conflicting airplane, it also provides commands that ensure separation. it's a very, very smart system. >> on board the dhl cargo jet, tcas instructs the crew to descend. the crew responds immediately, switching off the autopilot and beginning a descent. on board the russian airplane, the crew hears the opposite advisory. the two tcas units coordinated those commands to maximize the separation as quickly as possible. for this system to work, both pilots have to follow the commands of the tcas. >> when nielsen discovers that the two airplanes are in danger, he contacts the russian crew, unaware that tcas is issuing an advisory to climb, he instructs them to do the opposite and descend by 1,000 feet.

>> when you have conflicting commands, there is a short interval which the decision is, which one are we going to be follow? >> it was not a fully implemented standard around the world where when the automated system said to take corrective action that the pilots automatically followed without question. russia, their policies and procedures basically told the pilots that the air traffic controller has prominence or precedence, not the automated system. >> the russian crew is conflicted, but they follow the instructions of air traffic control and begin descending. >> you had one flight crew who's following the automation. you have another flight crew who's following instructions by the air traffic controller. now you had both airplanes descending instead of avoiding

each other by one climbing and one descending. >> the dhl cargo jet and the russian airplane are closing in at incredible speeds. >> you're talking airplanes that are moving basically 400, 500, 600 miles an hour. >> the closure rate is 16 miles a minute. it's much faster than most people can imagine. >> so all of a sudden now, decision making is very compressed because you don't have a lot of time. >> in the dark of night, the pilots' visibility is less than seven miles. >> from the time that you could see the airplane, recognize it was a potential conflict for collision and avoid it, there wasn't enough time.

the airplanes had physically covered so much ground that you could not visually avoid the collision. coming up, critical moments before a devastating collision. and the investigation takes a deadly twist. >> it was a crime in my mind of almost unimaginable magnitude.

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traffic, traffic. >> a dhl cargo jet and a russian chartered flight with 69 people on board, most of them children on a school trip, are on a collision course. the onboard traffic collision avoidance system, or tcas, has issued commands. >> climb, climb, climb. >> descend, descend, descend. >> unaware of the tcas commands, the air traffic controller instructs the russian crew to also descend. now the two airplanes are

seconds from disaster. by the time they see each other, it's too late. at nearly 35,000 feet, the two airplanes collide at almost a right angle. the dhl boeing 757's vertical stabilizers slices completely through the fuselage of the russian airplane. many of the passengers are pulled from the aircraft as it plunges toward the ground. in the nose of the airplane, the crew loses consciousness from the high-speed fall. the dhl cargo jet has lost control of its stabilizers. in another two minutes, they crash. the airplanes strike the ground north of the town of uberlingen, germany, with pieces of the wreckage landing only feet from houses. no one on the ground is injured, but all 71 people on board both airplanes are killed. nearby, the directors of a

school for children with special needs hear the crash. >> translator: i heard a loud bang and thunder and i thought, strange, is that a storm? but it couldn't be really. >> translator: i looked out and saw what looked like a rocket and a column of fire falling to the earth. >> translator: this is the area where the people found their death, most of whom were children, in a strip from here scattered through the woods. >> accident investigators begin a long process of collecting and analyzing the wreckage of the boeing 757 cargo jet and the russian tupolev airplane, preserved in this hangar.

>> translator: we are basically standing on the roof of the plane. and over there, we can see the left wing of the tupolev. and here you can see massive collision marks due to the contact with the vertical tail of the boeing 757. and if you look here, you can see that color that matches the red color of the empennage of the boeing. >> investigators determined if the tcas commands have been followed by the crews on both planes, they would have avoided a collision. >> technically if they'd both followed the tcas system in their respective aircraft, one aircraft would have climbed, the other would have descended and they would have avoided the conflict by vertical separation. >> investigators also conclude that shortcomings at skyguide, the swiss air traffic control system supervising the flights at the time of the accident, played a significant role. >> i don't find the word actually to describe the shock

we have, i have and the deep sadness we have, the whole crew, of skyguide. >> only one air traffic controller, peter nielsen was managing the airspace at the time of the incident. he received medical attention due to traumatic stress. but some people, like vitaly kaloyev blames the accident on the nielsen himself. a year and a half after the crash, a shocking act of violence. kaloyev travels to nielsen's home in switzerland and stabs him to death. >> the vigilante approach is an impediment to aviation safety for all of us because this action of the air traffic controller was not a willful disregard of procedure. that gentleman that evening did the very best that he could with what he had. for someone to take it upon themselves to commit a murder as a result of this, it goes

counter to everything that i know in aviation safety. it goes counter to everything that all of us in aviation safety strive to do. it was a crime in my mind of almost unimaginable magnitude. >> kaloyev is convicted of a murder in 2005. but two years later, he's released from prison after the courts rule that his mental condition at the time of the murder was not sufficiently considered at sentencing. >> translator: i want to express my gratitude to all russian people for their support. having served in prison, i did not feel like i was without. >> three of the four managers at skyguide are convicted of negligent homicide and given suspended prison terms of 6 to 15 months. the fourth is ordered to pay a fine. skyguide says they no longer use the single-manned operations

that violate regulations. >> one of the things that was really examined in this was the workload of the controller and his diversion of attention when it came to actually identifying the conflict and then providing timely conflict resolution prior to the event. >> the accident leads to a clear defining of the role of tcas. pilots around the world are now trained to give tcas advisories priority over the instructions from air traffic control. >> this accident showed the critical importance of a worldwide standard when we're talking about the technologies, particularly predictive technologies, so that all the pilots respond the same way and that way you don't have unexpected results like we got here.

they say the truth set you free not here. >> after months in the segregation unit, one is tested after he returns to general population. >> this is outrageous. every day the same thing. never have a smooth day. >> another inmate charged with a violent crime in the street. >> he had picked up a shol