Mayday (2013) s05e01 Episode Script
Invisible Killer
(THEME MUSIC) VOICEOVER: August 2, 1985.
Dallas, Texas.
It's a very hot day, even by Texas standards.
See y'all tomorrow.
Temperatures soar to 101 degrees.
Rain coming.
Should cool things down a bit.
In the late afternoon, William Mayberry is heading home from work.
The day's heat and humidity are having an effect on traffic at Dallas Fort Worth International Airport, DFW.
Roughly the size of Manhattan, DFW is the biggest airport in the world.
It's also one of the busiest.
The heat has triggered some afternoon thunderstorms at the airport .
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creating a backlog of planes waiting to take off.
American 631, you are cleared for take-off.
Air traffic controller Gene Skipworth is in the tower today.
He's been working there for 14 years.
With him is controller Mike Porter.
Skipworth was not asking for help.
Nothing seemed unusual, other than the fact that we were starting to get busy and aircraft were starting to pile up.
One of the many planes heading towards Skipworth's control is Delta Air Lines Flight 191.
MAN: (OVER TWO-WAY RADIO) Weather, 6,000, scattered.
1,000 scattered.
Visibility 1-0.
Temperature 1-0-1.
Wind calm.
- 101? - 101 degrees.
Yes, sir.
Captain Ed Conners and First Officer Rudy Price are two of Delta Airline's most experienced pilots.
Second Officer Nick Nassick is the other member of today's crew.
The crew is flying a 6-year-old L-1011 Tristar.
The L-1011 is billed as one of the safest planes in the sky.
There are 152 passengers and 11 crew members on board.
They're scheduled to land in Dallas just before 6:00 in the evening.
(BELL CHIMES) Good afternoon, ladies and gentlemen.
This is your captain speaking.
Hope you're enjoying your flight so far.
Traffic is backing up at Dallas.
All told, we'll be about 10 to 15 minutes late getting to the gate.
Please let us know if there's anything we can do to make your flight more comfortable.
The delay bothers Chris Meier.
He's a frequent business traveller who's in a hurry to get home to his family for the weekend.
I'd been down in Florida, Fort Lauderdale, for the last two weeks and it was a Friday afternoon and I was due to go home on Flight 191.
One of IBM's best-known executives is also on the flight.
Don Estridge led the development of the IBM PC.
He and his wife are travelling to Dallas for a family visit.
CONTROLLER: 963, turn right, heading 6-2-0.
En route from Florida to Texas, Delta 191 will be in communication with several controllers.
I'll turn you into Blue Ridge.
It'll be about 0-1 Every aircraft is guided along its flight path by a series of regional air route traffic control centres.
They direct each plane's speed and altitude.
1-9-1, descend and maintain, one-zero-thousand.
Join the Blue Ridge 0-1-0 radial and inbound.
We've a good area there to go through.
Captain Conners has some concerns about the route he's been given.
He sees a storm cell along that path and he doesn't want to fly through it.
Well, I'm looking at a cell at about a heading of 2-5-5.
It's a pretty good sized cell and I'd rather not got through it.
I'd rather go around it, one way or the other.
I've had about 60 aircraft go through this area out here, 10 to 12 miles wide.
They're getting a good ride.
No problem.
Well, I can see a cell now about heading 2-4-0.
When I can, I'll turn you into Blue Ridge.
It'll be about the 0-1-0 radial.
0-1-0.
Roger.
We're gonna hold you to that.
Captain Conners gets his way.
He's given permission to fly around the storm.
Once past it, he'll line up for a landing on Runway 17 Left.
I'm glad we didn't have to go through that mess.
Friday afternoons are a busy time at airports.
The afternoon rain is making this Friday even busier.
23-9 down to 6-18-96.
The main priority for the controller on duty is to keep the incoming planes a safe distance apart.
He wants them at least 4.
5km from each other.
That distance allows enough time for the violent air turbulence behind one plane to die down before the next plane touches down.
Right now, Conners and Price are getting too close to the plane just ahead of them - a corporate Learjet.
Delta 191, heavy, turn left 10 degrees.
Reduce speed to 1-8-0.
To put some distance between the two planes, the controller asks the Delta crew to slow to 180 knots Delta 191 .
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330km/h.
Wilco.
10-degree flaps, please.
RADIO ANNOUNCER: You're listening to Dallas 105 FM.
It's a wet one out there, folks.
Drive careful.
Heading home along Highway 114, William Mayberry will soon be passing DFW.
Flight 191 is now just 50km from the foot of the runway.
ATTENDANT: Ladies and gentlemen, we are starting our approach to DFW.
Please make sure your seats are in the upright position and your seatbelts are securely fastened.
The crew begins their final descent into the Dallas Fort Worth area.
CONTROLLER: Attention, all aircraft listening.
There's a little rain shower just north of the airport.
Conners now switches radio frequencies and contacts a local DFW airport traffic controller for approach instructions.
As the passengers and crew of Flight 191 prepare for their landing, a deadly force takes shape in their path.
Critical decisions and missed information conspire against them.
The crew will soon be engaged in a 47-second struggle, which will become one of the most important moments in the history of modern aviation.
Delta 191 is still closing in on the Learjet ahead of it.
Price and Conners need to slow down even further to put some distance between the two planes.
CONTROLLER: Delta 191, heavy, reduce speed to 1-5-0.
Speed to 1-5-0.
9km from Runway 17 Left, Delta 191 is handed over to another controller, Gene Skipworth, for final approach and landing.
(RAIN PELTS) Tower, Delta 191 heavy, out here in the rain, feels good.
Delta 191 Skipworth tells the crew to expect a manageable crosswind of up to 15 knots.
Winds, 0-9-0 at 5, gusts to 1-5.
Thank you, sir.
First Officer Price will be at the controls for the upcoming landing.
Pilots and copilots routinely alternate flying duties.
As Flight 191 is coming into land, William Mayberry is just north of the airport.
He's caught in the same storm that Price and Conners are just beginning to fly through.
Before landing check.
- Landing gear.
- Down.
Three green.
- Flaps.
Slats.
- 33-33.
Green lights.
The crew suddenly notices that they'll be flying into more than a bit of rain.
There's lightning coming out of that one.
What? There's lightning coming out of that one.
- Where? - Right ahead of us.
1,000 feet.
- I'll call 'em out to ya.
- Alright.
(LIGHTNING CRACKS) We were not getting any bad warnings from the weather or from other pilots, which we rely on, as they come through it.
They need to report to us, and they do, if they have turbulence or if they have trouble on final or ran into anything abnormal.
The Learjet ahead of Flight 191 lands safely.
Conners and Price are now less than a minute behind.
Without warning, the intensity of the storm increases.
The L-1011 is being pounded by a driving rain.
I knew we was getting ready to land but at the same time, you felt the surge, like the pilots was revving up the engine for something.
The plane's airspeed is increasing for no apparent reason.
Watch your speed.
Price pulls back on the throttles to slow the plane down.
and maintain it at the requested 150 knots.
The plane is just 180m from the ground.
You're gonna lose it all of a sudden.
There it is.
Then the plane drops rapidly.
(SCREAMING) It's as though an invisible force is pushing it to the ground.
Push it up! Push it way up! Way up! - Way up.
- Way up! The crew is pushing the plane's jet engines to their full power but can't get more speed or get the plane to climb.
CHRIS MEIER: So I pulled my seatbelt tight as I could but at the same time you could hear a pin drop.
Nobody was talkin'.
But I mean it got dead silence.
As suddenly as it began, the crisis seems to end.
The plane stops falling and begins to pick up some of the speed Conners and Price have been fighting for.
Phew! That's it.
But before the crew can take another breath, the plane drops again .
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rocking violently from side to side and then it dips wildly to the right.
And I just knew that we shouldn't be that close to the ground that soon.
Hang onto the sonofa! About 2km from the runway, it ploughs into a field and rockets towards Highway 114.
When we hit the ground, it felt like you was in a car, running over a row of tyres.
It was real bumpy.
The crew somehow manages to get the plane back in the air.
At that moment, Gene Skipworth catches sight of Delta 191.
He's gonna crash! Delta, go around! But it's too late.
The plane's engines slam into William Mayberry's car on Highway 114.
He is killed instantly.
The plane hits the ground again, north of the runway.
It's travelling more than 350km/h.
(SIRENS WAIL) It seemed like it was only a few seconds.
Five seconds at the most.
I dunno how long it was We wereeverything was stopped.
The resulting explosion is so powerful that the rear section of the plane is blasted backwards, away from the fireball.
Then, all of a sudden, you look up and it's just nothing there.
It'severything's gone.
You just see the whole big picture outside, like the plane just opened up.
Remarkably, the tail section containing the last 10 rows of seats is relatively intact.
People just thrown around on the ground, some with clothes on, some without clothes on, some were burned.
It was something that you can't describe unless you're there to see it.
It is something that you will never get out of your mind.
Help! Over here! Hang in there.
Help's on the way.
Then, as suddenly as it had started, the rain stops.
(SIRENS WAIL) It takes firefighters less than a minute to get to the crash.
MAN: And when I arrived on the scene, I truly believed that there wasn't anybody that had survived this plane crash 'cause there was just devastation everywhere.
What I hadn't pulled up on at the time was the wing section, which is the portion of the aircraft that carries the fuel, so there was a large amount of fuel and a large amount of flames.
The front of the plane has all but disintegrated.
MAN: I knew I had to get out there.
At the time I was a stringer for 'Time' magazine, worked with them on a part-time basis.
Called their Atlanta headquarters for this portion of the country.
They said one word.
"Go.
" Firefighters need only a few minutes to get the raging fire under control.
They then turn their attention to pulling survivors from the plane.
It wasn't until the fire started to subside a little bit that I saw the tail section, where there was some hope of some people surviving.
There were these two women that were walking through the smoke.
Ladies! Ladies, clear the area! Get out of the way.
Clear the area.
And it kinda surprised me so I knew that there was hope and that there were people out there.
Only 27 people survive the crash.
I had seen death before, as a medic in Vietnam, but it had never been aimed at civilians and certainly not on a mass casualty situation and certainly not this suddenly.
I could tell how bad it was.
You could see and smell and feel the death.
We felt like we did everything that we could and we were justyou know, we were just pleased that there were survivors.
I was scheduled to sit on aisle seat 15A and I told 'em that wouldn't be no good 'cause that was a non-smoking section.
I was a smoker, so I had to be in back.
That probably saved my life.
Captain Conners, First Officer Price and Second Officer Nassick are killed.
So are five other crew members and 128 passengers.
IBM's Don Estridge and his wife are among the dead.
In the tower, it was silence for probably one to two minutes, except for just an occasional transmission.
But, basically, it's just quiet and you just sit there, stunned, and wishing you could do anything to take it back.
This is a monumental crash.
Investigators from the National Transportation Safety Board arrive at DFW, determined to find the cause.
MAN: One of our field investigators would've been on scene, trying to locate the flight data recorder and the cockpit voice recorder, which is, um, you know, a very important part of the investigation.
Investigators begin looking for evidence of mechanical failure.
They examine the wreckage for clues that the plane was not responding to the pilot's command.
It's essential in any approach or departure accident to establish what the airplane's configuration was, to assure that it was not a factor in the accident.
Everything was normal on this aircraft.
Investigators turn their attention away from the plane .
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and to the skies.
After any accident in commercial aviation, there are theories galore.
A couple of them prevalent that evening - first, that lightning had struck the airplane, secondly, that it had been hit by a mini tornado.
There's lightning coming out of that one.
- Where? - Right ahead of us.
15 different witnesses, including flight crews, report seeing lightning as Flight 191 was descending towards the runway.
The investigators have to consider the possibility that Flight 191 was hit by lightning.
Lighting is always something that you have to investigate to determine the possibility that lightning disabled some part of the airplane.
In 1963, a Boeing 707 was struck by lightning.
The lightning ignited the fuel in the plane's tank.
The plane crashed.
81 people died.
There had been a handful of similar crashes since then.
Key pieces of wreckage from Flight 191 are taken to the NTSB lab in Washington, DC.
Bud Laynor is the investigator in charge of examining the wreckage as well as the data from the plane's cockpit voice recorder.
That sometimes might be very difficult to find, to determine where the airplane might have been struck by lightning and where the exit point was.
PRICE: (ON TAPE) There's lightning coming out of that one.
- CONNERS: (ON TAPE) Where? - Right ahead of us.
If the plane was hit by lightning, there would be evidence left behind.
A device called a static-discharge wick is attached to the trailing edge of an aircraft's wings.
It redirects static electricity into the outside air instead of into the plane, where the charge could cause a fire.
If the plane was hit by lightning, one of the pieces that would be visibly damaged is the static-discharge wick.
Nothing there.
With lightning ruled out, investigators went looking elsewhere.
They would soon discover the real culprit.
It had actually been caught on tape.
Bud Laynor still doesn't know what slammed Flight 191 into the ground.
But soon, he finds the clues he needs on the plane's flight data recorder.
It logs every adjustment pilots make to the plane's controls.
The device also records external elements like temperature, wind speed, altitude and air pressure.
Whatever Conners and Price were fighting, there's a good chance it left its fingerprints on the flight data recorder.
LAYNOR: This flight data recorder gave us several parameters we didn't have before - engine power, longitudinal acceleration.
And those kinds of parameters really enabled us to do a more in-depth analysis.
The plane's data recorder has documented a combination of rapidly shifting winds.
Then it shifts to a down draught.
In a matter of seconds, the plane was hit with strong winds from the front, then from above, and then from behind.
There you have it.
For Bud Laynor, that sequence could only mean one thing - a microburst.
A microburst is a violent shaft of air falling from a storm cloud.
Back in 1985, few people knew more about encounters between microbursts and airplanes than John McCarthy.
If you're at the kitchen sink and you turn on the water and it goes straight down and it splashes out in all directions.
And that's kind of what a microburst is, except that it is extremely bad news if you're an airplane flying through it at low altitude.
A plane first faces a strong headwind, which lifts the plane skyward then a down draught, which slams it towards the ground.
Finally, the microburst delivers its most dangerous punch - the tailwind.
And you would get a rapid descent.
A loss of lift and a rapid descent towards the ground and easily crash the airplane.
A plane's wings need a steady flow of air moving over them.
That's what gives them their lift.
By inhibiting that flow, the tailwind reduces lift.
There's no better recipe for a microburst than the weather conditions at Dallas Fort Worth on the day of the crash.
It had been extremely hot all day.
And hot air rises.
When that hot air meets the cold moist air in the storm clouds, it cools instantly and rushes violently back to earth.
A microburst.
It is a tiny thing, meteorologically speaking, compared to a big storm or a snowstorm or a hurricane.
It's just like a needle in a haystack.
At its maximum strength, it's no more than two miles across and it lasts no more than 15 minutes.
So if you look at that little space and time window, it's very small.
And so, the probability of hitting one is little.
The odds may be slim, but planes do fly into microbursts.
In 1975, an Eastern Airlines flight landing in New York flew into a microburst.
It slammed the plane into the ground, killing 113 people.
Then, in 1982, a microburst killed another 153 people when it struck a Pan Am 727 taking off from New Orleans.
It was clear that 136 people on Flight 191 had become the latest victims of a microburst.
Investigators had their culprit.
Unbelievable.
And thanks to Flight 191's advanced data recorder, they could paint a remarkably accurate picture of it.
The killer had, essentially, been caught on tape.
But what the flight data recorder doesn't explain is how such an experienced crew fell victim to a killer You're in good shape.
.
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they were all trained to overcome.
When Laynor compares the pilots' actions to the actions of the microburst Watch your speed.
.
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he uncovers details of a fight to the death.
A fight that the Delta pilots almost won.
You're gonna lose it all of a sudden.
There it is.
He seemed to know what he was going to hit.
Watch your speed.
The increase in airspeed prompted First Officer Price to reduce power to his engines.
Power that he would desperately need in just a few seconds.
You're gonna lose it all of a sudden.
There it is.
When Price and Conners entered the down draught Push it up.
.
.
they were less than 250m from the ground.
The captain knew the characteristics of a microburst.
He'd obviously been given an introduction to windshear and microburst characteristics in his flight training.
When Conners and Price encountered the microburst's tailwind, there was very little they could do.
They had insufficient speed and altitude with which to manoeuvre.
If a pilot encounters a strong tailwind at 3,000m, he can point his nose down and dive to pick up speed and generate lift.
It's called "trading altitude for airspeed".
But that trade wasn't available to Price and Conners.
They were just 150m off the ground when the tailwind struck.
The only way for them to gain airspeed was from their engines.
Push it up.
Way up.
Copilot responds, airplane stabilises.
I can see that most pilots would say, "Well, we're thrilled with that.
"And the rain's gonna stop.
We're gonna land.
" Momentarily, their efforts seem to pay off.
Their airspeed increases, their plunge is halted.
But with Flight 191 less than 150m from the ground, this particular microburst delivered the ultimate blow .
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a fierce crosswind that forces their plane to bank dangerously to the right.
Hang onto the sonofa! Combined with the microburst's other winds, the crew was defenceless.
CONNERS: (ON TAPE) TOGA! 'TOGA' is Take-Off, Go-Around mode.
And what it means to a pilot in that regime of flying is, "Let's abandon the approach.
"We're no longer gonna try to land this airplane.
"We want to do everything we can now "to survive the wind condition that we've entered.
" The skill and experience of the pilots were no match for this microburst.
It was too big, its winds too powerful and unpredictable.
The entire fight lasted only 47 seconds.
A Delta Air Lines L-1011 crashes after entering a storm near Dallas.
The pilots of Delta Flight 191 did their very best to recover from this situation and it didn't work out.
Investigators were left with one perplexing question - why had Conners flown into the storm in the first place? Prior to 1985, the radars on board the aircraft were built to detect thunderstorms.
Essentially, heavy areas of precipitation.
They were not effective, they weren't even designed to detect the microburst.
So those radars were essentially useless at low altitudes for looking at the microburst phenomena.
Microbursts are invisible but they generally emerge from storm clouds.
That's why pilots are trained not to fly into storms if they see lightning.
CONNERS: It's a pretty good sized cell, and I'd rather not go through it.
I'd rather go around it, one way or the other.
When I can, I'll turn you into Blue Ridge.
It'll be about 0-1-0 radial.
0-1-0.
Roger.
Captain Conners was not a risk taker.
He was known as a cautious pilot.
I'm glad we didn't have to go through that mess.
JOHN McCARTHY: It's hard to blame the aircrew.
Their job is to avoid thunderstorms and there's probably a forecast for thunderstorms every day at Dallas in the summertime.
Which ones do you avoid and it's No.
It's a very difficult problem.
Earlier in the flight, Conners had flown around bad weather.
Investigators can only conclude that he underestimated the storm in his path at the foot of Runway 17 Left.
When you're in a landing sequence at an airport like Dallas or Atlanta or Chicago and you see other airplanes ahead that are landing uneventfully, you might get the impression that there's a thunderstorm there but I'm gonna pass through it very quickly and it's not gonna be a factor for me.
Airports like DFW have sophisticated systems in place to provide weather information to pilots.
A thunderstorm at the end of a runway is the kind of threat they were designed to identify.
But this deadly storm managed to foil those systems.
As Flight 191 was approaching the airport, the weather at DFW was changing very quickly.
CONTROLLER: Attention, all aircraft listening - there's a little rain shower just north of the airport.
Captain Conners heard that part of the message but then he switched his radio frequency for his final landing instructions.
The Delta crew never heard the last part of this message about weather ahead.
There's a little bitty thunderstorm sitting right on the final.
There was an observation two minutes before the accident that there was a wall of water at the threshold of the runway.
It's been my contention that that information would have been very important to the flight crew.
Radar readouts from the day of the crash indicate that the storm cell Conners and Price flew into grew out of nothing in a matter of minutes.
This is two minutes before the accident.
The readout shows the beginnings of a weather cell at the foot of Runway 17 Left.
This is three minutes after the accident.
Then we have a new cell right at the threshold of the runway that wasn't evident in the previous picture.
This explains why Rufus Lewis was able to land his Learjet.
The microburst was just beginning to form when he was approaching the runway.
Many people think that there was a huge vertical development that the pilots recognised and they just decided to go fly through it anyway and I maintain, and I think the evidence proves it, that that was not the case.
They didn't recognise this new developing cell.
They did get into the storm beneath the cell .
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but it was heavy rain, they weren't worried about that.
Then the hammer fell.
It was too late.
(CRACK OF THUNDER) JOHN McCARTHY: It's small.
It's the length of a runway, roughly, and it doesn't last very long so it's something that can happen so quickly that many accidents have occurred because nobody knew it was there.
The storm arrived at the foot of Runway 17 Left virtually unannounced.
But once there, it attracted a lot of attention.
Pilots on the ground as well as trained weather observers saw the worsening storm.
But they all saw it too late to warn the crew of Delta 191.
The storm did show up on a radar screen at the Fort Worth Air Traffic Control Centre.
But at the time of the crash, the meteorologist on duty was in the cafeteria on a meal break.
JOHN McCARTHY: If the flight crew had had any idea that there would be a severe event in front of them they would have missed the approach.
Investigators conclude that the Delta crash was caused by the pilot's decision to continue their approach into the storm - a decision that was made because the crew wasn't warned about the hazard.
In 1985, there were basic systems at airports that could detect dangerous winds but they could not detect a microburst.
On the ground there were systems called Low Level Windshear Alerting Systems that primarily look for differences of wind speed around the airport or on the airport.
Unfortunately, these sensors tend to be spaced so far apart that a microburst could actually exist in between them and escape detection, or at least detection in time to warn a pilot of the threat.
But a microburst detection system to overcome this problem had been developed.
It was being tested in Denver and working very well.
What we found out is our Doppler radar, which is on the ground, is incredibly effective in detecting microbursts and in fact, it can detect about 98% of a microburst.
Conventional radar uses radio waves to measure precipitation inside a storm.
Doppler also sends out radio waves.
But by measuring the frequency of returning waves, Doppler can also calculate the movement of the winds inside a storm.
If you look through the Doppler radar, you see a part of it that's going away from the radar and a part that's coming towards the radar and if it's small, it's absolutely a microburst.
It can be nothing else.
So it has what we call "an unambiguous signature of a microburst", which means we got it.
Since Doppler radar could see a microburst, controllers could use it to warn crews of their presence.
The Denver research resulted in an important new system at airports - Terminal Doppler Weather Radar.
When the system detects dangerous conditions, it relays a warning to air traffic controllers .
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who can then alert pilots.
Flight 236, microburst alert.
After the crash of Delta 191, the Federal Aviation Authority, the FAA, hurried to install Terminal Doppler Weather Radar at high-risk airports.
Dallas Fort Worth was one of the first.
The domes containing the specialised radar are now a common fixture at major airports around the world.
But radar on the ground can't get the warning to the pilots fast enough.
We also have an issue of ground-based systems in that it takes time to communicate the threat to the crew.
The system has to detect it on the ground.
It would typically go to a control position in the control tower and be relayed by voice to the pilot, which can introduce a delay of 10, 15, 20 seconds, which could be very critical.
Planes also needed on-board microburst detection.
A team from NASA began developing such a system by flying into the most dangerous microbursts they could find.
MAN: (OVER TWO-WAY RADIO) Here we go.
- Take it? - Straight ahead.
By risking their own lives, they would eventually save thousands of others.
NARRATOR: The crash of Delta 191 showed that seconds count when planes encounter a microburst.
You're gonna lose it all of a sudden.
There it is.
Increasing alert times Push it up! Way up! .
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could save more lives, especially if a microburst detector was mounted right on the plane.
If you can provide the airplane with 10, 15, 20 seconds of advanced warning, pilots push the throttles up, they build airspeed, they build altitude, they build energy, it's like money in the bank - by the time they get to the microburst, during a recovery, they can survive.
Aviation experts had to find a way to give all pilots those critical 20 seconds.
To develop that technology, they would embark on a high-risk, unprecedented research project.
They would fly a 737 into the most severe microbursts they could find.
We did a very careful risk analysis of all the possible dangers that could occur and initially, you know, the first reaction was, "You want do WHAT with an aeroplane? "You want to fly it through a microburst?" In the summer of 1991, NASA modified a Boeing 737 and went hunting for microbursts.
The idea was to identify on-board technology that could warn pilots of a microburst in their path.
The airborne solution brings detection right into the cockpit so the pilot sees exactly what's in front of the aircraft, and when an alert is given, there's no time delay.
MAN: (OVER TWO-WAY RADIO) Groundspeed 234.
The NASA researchers were testing three separate systems for detecting microbursts.
Modified Doppler radar housed in the 737's nose, a laser radar under its forward cargo bay and a side-mounted infra-red device to measure changes in air temperature.
Each of those systems was wired to banks of computers in the plane's cabin.
A spotter on the ground could find a microburst and quickly direct the plane towards it.
We started with very, very weak microburst.
Again, we had the ground-based radar telling us what we were about to go into, so we started with very weak microburst, gained experience, then gradually worked up to stronger and stronger ones.
You would see the rain begin to fall and you would feel a sinking feeling.
You would be a little settling, a little like an elevator starting down.
So any apprehension that the crew may have had initially about going through them was actually replaced later with joy at finding them.
MAN: Here comes the centre of the target.
Right .
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now.
242 on the groundspeed.
Wind's gone away.
Look for a tailwind.
Watch.
Loss of altitude there too.
There - the wind's gone around the tail at 10 knots.
Good strong down draught in the middle of it.
Just sucked 100ft in almost no time at all.
Saw a good performance decrease too.
We're about 850 and we dropped to 750.
Beautiful.
The project proved that the forward-looking Doppler radar was the only system that could consistently give pilots advanced warnings of a microburst ahead.
What we found was that the Doppler radars could detect an extremely wide variety of microburst.
There's lightning coming out of that one.
If the crew of Delta 191 had a system to warn them of microbursts, they could have boosted power to their engines and started climbing before they encountered it.
That might have given them the speed and the altitude which they sorely lacked when they began their battle with the storm.
The Langley flight tests had, in effect, tamed the microburst menace.
After the NASA tests, the FAA certified a Doppler-based warning system for planes.
Today, forward-looking Doppler radar is standard equipment on commercial flights around the world.
The good news out of all of this tragedy .
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is so many things have now happened, from radar to ground-based systems to airborne systems and especially to training for pilots, we think that microburst accidents are a thing of the past.
JEROME CHANDLER: If there is one crash that we can look back on now and say, "This made things safer because we learned from it," it was Delta 191.
The changes made after the crash of Delta 191 have saved countless lives.
Captain Conners and First Officer Price lost their fight against a microburst but their struggle did manage to expose and disarm an invisible killer.
Dallas, Texas.
It's a very hot day, even by Texas standards.
See y'all tomorrow.
Temperatures soar to 101 degrees.
Rain coming.
Should cool things down a bit.
In the late afternoon, William Mayberry is heading home from work.
The day's heat and humidity are having an effect on traffic at Dallas Fort Worth International Airport, DFW.
Roughly the size of Manhattan, DFW is the biggest airport in the world.
It's also one of the busiest.
The heat has triggered some afternoon thunderstorms at the airport .
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creating a backlog of planes waiting to take off.
American 631, you are cleared for take-off.
Air traffic controller Gene Skipworth is in the tower today.
He's been working there for 14 years.
With him is controller Mike Porter.
Skipworth was not asking for help.
Nothing seemed unusual, other than the fact that we were starting to get busy and aircraft were starting to pile up.
One of the many planes heading towards Skipworth's control is Delta Air Lines Flight 191.
MAN: (OVER TWO-WAY RADIO) Weather, 6,000, scattered.
1,000 scattered.
Visibility 1-0.
Temperature 1-0-1.
Wind calm.
- 101? - 101 degrees.
Yes, sir.
Captain Ed Conners and First Officer Rudy Price are two of Delta Airline's most experienced pilots.
Second Officer Nick Nassick is the other member of today's crew.
The crew is flying a 6-year-old L-1011 Tristar.
The L-1011 is billed as one of the safest planes in the sky.
There are 152 passengers and 11 crew members on board.
They're scheduled to land in Dallas just before 6:00 in the evening.
(BELL CHIMES) Good afternoon, ladies and gentlemen.
This is your captain speaking.
Hope you're enjoying your flight so far.
Traffic is backing up at Dallas.
All told, we'll be about 10 to 15 minutes late getting to the gate.
Please let us know if there's anything we can do to make your flight more comfortable.
The delay bothers Chris Meier.
He's a frequent business traveller who's in a hurry to get home to his family for the weekend.
I'd been down in Florida, Fort Lauderdale, for the last two weeks and it was a Friday afternoon and I was due to go home on Flight 191.
One of IBM's best-known executives is also on the flight.
Don Estridge led the development of the IBM PC.
He and his wife are travelling to Dallas for a family visit.
CONTROLLER: 963, turn right, heading 6-2-0.
En route from Florida to Texas, Delta 191 will be in communication with several controllers.
I'll turn you into Blue Ridge.
It'll be about 0-1 Every aircraft is guided along its flight path by a series of regional air route traffic control centres.
They direct each plane's speed and altitude.
1-9-1, descend and maintain, one-zero-thousand.
Join the Blue Ridge 0-1-0 radial and inbound.
We've a good area there to go through.
Captain Conners has some concerns about the route he's been given.
He sees a storm cell along that path and he doesn't want to fly through it.
Well, I'm looking at a cell at about a heading of 2-5-5.
It's a pretty good sized cell and I'd rather not got through it.
I'd rather go around it, one way or the other.
I've had about 60 aircraft go through this area out here, 10 to 12 miles wide.
They're getting a good ride.
No problem.
Well, I can see a cell now about heading 2-4-0.
When I can, I'll turn you into Blue Ridge.
It'll be about the 0-1-0 radial.
0-1-0.
Roger.
We're gonna hold you to that.
Captain Conners gets his way.
He's given permission to fly around the storm.
Once past it, he'll line up for a landing on Runway 17 Left.
I'm glad we didn't have to go through that mess.
Friday afternoons are a busy time at airports.
The afternoon rain is making this Friday even busier.
23-9 down to 6-18-96.
The main priority for the controller on duty is to keep the incoming planes a safe distance apart.
He wants them at least 4.
5km from each other.
That distance allows enough time for the violent air turbulence behind one plane to die down before the next plane touches down.
Right now, Conners and Price are getting too close to the plane just ahead of them - a corporate Learjet.
Delta 191, heavy, turn left 10 degrees.
Reduce speed to 1-8-0.
To put some distance between the two planes, the controller asks the Delta crew to slow to 180 knots Delta 191 .
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330km/h.
Wilco.
10-degree flaps, please.
RADIO ANNOUNCER: You're listening to Dallas 105 FM.
It's a wet one out there, folks.
Drive careful.
Heading home along Highway 114, William Mayberry will soon be passing DFW.
Flight 191 is now just 50km from the foot of the runway.
ATTENDANT: Ladies and gentlemen, we are starting our approach to DFW.
Please make sure your seats are in the upright position and your seatbelts are securely fastened.
The crew begins their final descent into the Dallas Fort Worth area.
CONTROLLER: Attention, all aircraft listening.
There's a little rain shower just north of the airport.
Conners now switches radio frequencies and contacts a local DFW airport traffic controller for approach instructions.
As the passengers and crew of Flight 191 prepare for their landing, a deadly force takes shape in their path.
Critical decisions and missed information conspire against them.
The crew will soon be engaged in a 47-second struggle, which will become one of the most important moments in the history of modern aviation.
Delta 191 is still closing in on the Learjet ahead of it.
Price and Conners need to slow down even further to put some distance between the two planes.
CONTROLLER: Delta 191, heavy, reduce speed to 1-5-0.
Speed to 1-5-0.
9km from Runway 17 Left, Delta 191 is handed over to another controller, Gene Skipworth, for final approach and landing.
(RAIN PELTS) Tower, Delta 191 heavy, out here in the rain, feels good.
Delta 191 Skipworth tells the crew to expect a manageable crosswind of up to 15 knots.
Winds, 0-9-0 at 5, gusts to 1-5.
Thank you, sir.
First Officer Price will be at the controls for the upcoming landing.
Pilots and copilots routinely alternate flying duties.
As Flight 191 is coming into land, William Mayberry is just north of the airport.
He's caught in the same storm that Price and Conners are just beginning to fly through.
Before landing check.
- Landing gear.
- Down.
Three green.
- Flaps.
Slats.
- 33-33.
Green lights.
The crew suddenly notices that they'll be flying into more than a bit of rain.
There's lightning coming out of that one.
What? There's lightning coming out of that one.
- Where? - Right ahead of us.
1,000 feet.
- I'll call 'em out to ya.
- Alright.
(LIGHTNING CRACKS) We were not getting any bad warnings from the weather or from other pilots, which we rely on, as they come through it.
They need to report to us, and they do, if they have turbulence or if they have trouble on final or ran into anything abnormal.
The Learjet ahead of Flight 191 lands safely.
Conners and Price are now less than a minute behind.
Without warning, the intensity of the storm increases.
The L-1011 is being pounded by a driving rain.
I knew we was getting ready to land but at the same time, you felt the surge, like the pilots was revving up the engine for something.
The plane's airspeed is increasing for no apparent reason.
Watch your speed.
Price pulls back on the throttles to slow the plane down.
and maintain it at the requested 150 knots.
The plane is just 180m from the ground.
You're gonna lose it all of a sudden.
There it is.
Then the plane drops rapidly.
(SCREAMING) It's as though an invisible force is pushing it to the ground.
Push it up! Push it way up! Way up! - Way up.
- Way up! The crew is pushing the plane's jet engines to their full power but can't get more speed or get the plane to climb.
CHRIS MEIER: So I pulled my seatbelt tight as I could but at the same time you could hear a pin drop.
Nobody was talkin'.
But I mean it got dead silence.
As suddenly as it began, the crisis seems to end.
The plane stops falling and begins to pick up some of the speed Conners and Price have been fighting for.
Phew! That's it.
But before the crew can take another breath, the plane drops again .
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rocking violently from side to side and then it dips wildly to the right.
And I just knew that we shouldn't be that close to the ground that soon.
Hang onto the sonofa! About 2km from the runway, it ploughs into a field and rockets towards Highway 114.
When we hit the ground, it felt like you was in a car, running over a row of tyres.
It was real bumpy.
The crew somehow manages to get the plane back in the air.
At that moment, Gene Skipworth catches sight of Delta 191.
He's gonna crash! Delta, go around! But it's too late.
The plane's engines slam into William Mayberry's car on Highway 114.
He is killed instantly.
The plane hits the ground again, north of the runway.
It's travelling more than 350km/h.
(SIRENS WAIL) It seemed like it was only a few seconds.
Five seconds at the most.
I dunno how long it was We wereeverything was stopped.
The resulting explosion is so powerful that the rear section of the plane is blasted backwards, away from the fireball.
Then, all of a sudden, you look up and it's just nothing there.
It'severything's gone.
You just see the whole big picture outside, like the plane just opened up.
Remarkably, the tail section containing the last 10 rows of seats is relatively intact.
People just thrown around on the ground, some with clothes on, some without clothes on, some were burned.
It was something that you can't describe unless you're there to see it.
It is something that you will never get out of your mind.
Help! Over here! Hang in there.
Help's on the way.
Then, as suddenly as it had started, the rain stops.
(SIRENS WAIL) It takes firefighters less than a minute to get to the crash.
MAN: And when I arrived on the scene, I truly believed that there wasn't anybody that had survived this plane crash 'cause there was just devastation everywhere.
What I hadn't pulled up on at the time was the wing section, which is the portion of the aircraft that carries the fuel, so there was a large amount of fuel and a large amount of flames.
The front of the plane has all but disintegrated.
MAN: I knew I had to get out there.
At the time I was a stringer for 'Time' magazine, worked with them on a part-time basis.
Called their Atlanta headquarters for this portion of the country.
They said one word.
"Go.
" Firefighters need only a few minutes to get the raging fire under control.
They then turn their attention to pulling survivors from the plane.
It wasn't until the fire started to subside a little bit that I saw the tail section, where there was some hope of some people surviving.
There were these two women that were walking through the smoke.
Ladies! Ladies, clear the area! Get out of the way.
Clear the area.
And it kinda surprised me so I knew that there was hope and that there were people out there.
Only 27 people survive the crash.
I had seen death before, as a medic in Vietnam, but it had never been aimed at civilians and certainly not on a mass casualty situation and certainly not this suddenly.
I could tell how bad it was.
You could see and smell and feel the death.
We felt like we did everything that we could and we were justyou know, we were just pleased that there were survivors.
I was scheduled to sit on aisle seat 15A and I told 'em that wouldn't be no good 'cause that was a non-smoking section.
I was a smoker, so I had to be in back.
That probably saved my life.
Captain Conners, First Officer Price and Second Officer Nassick are killed.
So are five other crew members and 128 passengers.
IBM's Don Estridge and his wife are among the dead.
In the tower, it was silence for probably one to two minutes, except for just an occasional transmission.
But, basically, it's just quiet and you just sit there, stunned, and wishing you could do anything to take it back.
This is a monumental crash.
Investigators from the National Transportation Safety Board arrive at DFW, determined to find the cause.
MAN: One of our field investigators would've been on scene, trying to locate the flight data recorder and the cockpit voice recorder, which is, um, you know, a very important part of the investigation.
Investigators begin looking for evidence of mechanical failure.
They examine the wreckage for clues that the plane was not responding to the pilot's command.
It's essential in any approach or departure accident to establish what the airplane's configuration was, to assure that it was not a factor in the accident.
Everything was normal on this aircraft.
Investigators turn their attention away from the plane .
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and to the skies.
After any accident in commercial aviation, there are theories galore.
A couple of them prevalent that evening - first, that lightning had struck the airplane, secondly, that it had been hit by a mini tornado.
There's lightning coming out of that one.
- Where? - Right ahead of us.
15 different witnesses, including flight crews, report seeing lightning as Flight 191 was descending towards the runway.
The investigators have to consider the possibility that Flight 191 was hit by lightning.
Lighting is always something that you have to investigate to determine the possibility that lightning disabled some part of the airplane.
In 1963, a Boeing 707 was struck by lightning.
The lightning ignited the fuel in the plane's tank.
The plane crashed.
81 people died.
There had been a handful of similar crashes since then.
Key pieces of wreckage from Flight 191 are taken to the NTSB lab in Washington, DC.
Bud Laynor is the investigator in charge of examining the wreckage as well as the data from the plane's cockpit voice recorder.
That sometimes might be very difficult to find, to determine where the airplane might have been struck by lightning and where the exit point was.
PRICE: (ON TAPE) There's lightning coming out of that one.
- CONNERS: (ON TAPE) Where? - Right ahead of us.
If the plane was hit by lightning, there would be evidence left behind.
A device called a static-discharge wick is attached to the trailing edge of an aircraft's wings.
It redirects static electricity into the outside air instead of into the plane, where the charge could cause a fire.
If the plane was hit by lightning, one of the pieces that would be visibly damaged is the static-discharge wick.
Nothing there.
With lightning ruled out, investigators went looking elsewhere.
They would soon discover the real culprit.
It had actually been caught on tape.
Bud Laynor still doesn't know what slammed Flight 191 into the ground.
But soon, he finds the clues he needs on the plane's flight data recorder.
It logs every adjustment pilots make to the plane's controls.
The device also records external elements like temperature, wind speed, altitude and air pressure.
Whatever Conners and Price were fighting, there's a good chance it left its fingerprints on the flight data recorder.
LAYNOR: This flight data recorder gave us several parameters we didn't have before - engine power, longitudinal acceleration.
And those kinds of parameters really enabled us to do a more in-depth analysis.
The plane's data recorder has documented a combination of rapidly shifting winds.
Then it shifts to a down draught.
In a matter of seconds, the plane was hit with strong winds from the front, then from above, and then from behind.
There you have it.
For Bud Laynor, that sequence could only mean one thing - a microburst.
A microburst is a violent shaft of air falling from a storm cloud.
Back in 1985, few people knew more about encounters between microbursts and airplanes than John McCarthy.
If you're at the kitchen sink and you turn on the water and it goes straight down and it splashes out in all directions.
And that's kind of what a microburst is, except that it is extremely bad news if you're an airplane flying through it at low altitude.
A plane first faces a strong headwind, which lifts the plane skyward then a down draught, which slams it towards the ground.
Finally, the microburst delivers its most dangerous punch - the tailwind.
And you would get a rapid descent.
A loss of lift and a rapid descent towards the ground and easily crash the airplane.
A plane's wings need a steady flow of air moving over them.
That's what gives them their lift.
By inhibiting that flow, the tailwind reduces lift.
There's no better recipe for a microburst than the weather conditions at Dallas Fort Worth on the day of the crash.
It had been extremely hot all day.
And hot air rises.
When that hot air meets the cold moist air in the storm clouds, it cools instantly and rushes violently back to earth.
A microburst.
It is a tiny thing, meteorologically speaking, compared to a big storm or a snowstorm or a hurricane.
It's just like a needle in a haystack.
At its maximum strength, it's no more than two miles across and it lasts no more than 15 minutes.
So if you look at that little space and time window, it's very small.
And so, the probability of hitting one is little.
The odds may be slim, but planes do fly into microbursts.
In 1975, an Eastern Airlines flight landing in New York flew into a microburst.
It slammed the plane into the ground, killing 113 people.
Then, in 1982, a microburst killed another 153 people when it struck a Pan Am 727 taking off from New Orleans.
It was clear that 136 people on Flight 191 had become the latest victims of a microburst.
Investigators had their culprit.
Unbelievable.
And thanks to Flight 191's advanced data recorder, they could paint a remarkably accurate picture of it.
The killer had, essentially, been caught on tape.
But what the flight data recorder doesn't explain is how such an experienced crew fell victim to a killer You're in good shape.
.
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they were all trained to overcome.
When Laynor compares the pilots' actions to the actions of the microburst Watch your speed.
.
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he uncovers details of a fight to the death.
A fight that the Delta pilots almost won.
You're gonna lose it all of a sudden.
There it is.
He seemed to know what he was going to hit.
Watch your speed.
The increase in airspeed prompted First Officer Price to reduce power to his engines.
Power that he would desperately need in just a few seconds.
You're gonna lose it all of a sudden.
There it is.
When Price and Conners entered the down draught Push it up.
.
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they were less than 250m from the ground.
The captain knew the characteristics of a microburst.
He'd obviously been given an introduction to windshear and microburst characteristics in his flight training.
When Conners and Price encountered the microburst's tailwind, there was very little they could do.
They had insufficient speed and altitude with which to manoeuvre.
If a pilot encounters a strong tailwind at 3,000m, he can point his nose down and dive to pick up speed and generate lift.
It's called "trading altitude for airspeed".
But that trade wasn't available to Price and Conners.
They were just 150m off the ground when the tailwind struck.
The only way for them to gain airspeed was from their engines.
Push it up.
Way up.
Copilot responds, airplane stabilises.
I can see that most pilots would say, "Well, we're thrilled with that.
"And the rain's gonna stop.
We're gonna land.
" Momentarily, their efforts seem to pay off.
Their airspeed increases, their plunge is halted.
But with Flight 191 less than 150m from the ground, this particular microburst delivered the ultimate blow .
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a fierce crosswind that forces their plane to bank dangerously to the right.
Hang onto the sonofa! Combined with the microburst's other winds, the crew was defenceless.
CONNERS: (ON TAPE) TOGA! 'TOGA' is Take-Off, Go-Around mode.
And what it means to a pilot in that regime of flying is, "Let's abandon the approach.
"We're no longer gonna try to land this airplane.
"We want to do everything we can now "to survive the wind condition that we've entered.
" The skill and experience of the pilots were no match for this microburst.
It was too big, its winds too powerful and unpredictable.
The entire fight lasted only 47 seconds.
A Delta Air Lines L-1011 crashes after entering a storm near Dallas.
The pilots of Delta Flight 191 did their very best to recover from this situation and it didn't work out.
Investigators were left with one perplexing question - why had Conners flown into the storm in the first place? Prior to 1985, the radars on board the aircraft were built to detect thunderstorms.
Essentially, heavy areas of precipitation.
They were not effective, they weren't even designed to detect the microburst.
So those radars were essentially useless at low altitudes for looking at the microburst phenomena.
Microbursts are invisible but they generally emerge from storm clouds.
That's why pilots are trained not to fly into storms if they see lightning.
CONNERS: It's a pretty good sized cell, and I'd rather not go through it.
I'd rather go around it, one way or the other.
When I can, I'll turn you into Blue Ridge.
It'll be about 0-1-0 radial.
0-1-0.
Roger.
Captain Conners was not a risk taker.
He was known as a cautious pilot.
I'm glad we didn't have to go through that mess.
JOHN McCARTHY: It's hard to blame the aircrew.
Their job is to avoid thunderstorms and there's probably a forecast for thunderstorms every day at Dallas in the summertime.
Which ones do you avoid and it's No.
It's a very difficult problem.
Earlier in the flight, Conners had flown around bad weather.
Investigators can only conclude that he underestimated the storm in his path at the foot of Runway 17 Left.
When you're in a landing sequence at an airport like Dallas or Atlanta or Chicago and you see other airplanes ahead that are landing uneventfully, you might get the impression that there's a thunderstorm there but I'm gonna pass through it very quickly and it's not gonna be a factor for me.
Airports like DFW have sophisticated systems in place to provide weather information to pilots.
A thunderstorm at the end of a runway is the kind of threat they were designed to identify.
But this deadly storm managed to foil those systems.
As Flight 191 was approaching the airport, the weather at DFW was changing very quickly.
CONTROLLER: Attention, all aircraft listening - there's a little rain shower just north of the airport.
Captain Conners heard that part of the message but then he switched his radio frequency for his final landing instructions.
The Delta crew never heard the last part of this message about weather ahead.
There's a little bitty thunderstorm sitting right on the final.
There was an observation two minutes before the accident that there was a wall of water at the threshold of the runway.
It's been my contention that that information would have been very important to the flight crew.
Radar readouts from the day of the crash indicate that the storm cell Conners and Price flew into grew out of nothing in a matter of minutes.
This is two minutes before the accident.
The readout shows the beginnings of a weather cell at the foot of Runway 17 Left.
This is three minutes after the accident.
Then we have a new cell right at the threshold of the runway that wasn't evident in the previous picture.
This explains why Rufus Lewis was able to land his Learjet.
The microburst was just beginning to form when he was approaching the runway.
Many people think that there was a huge vertical development that the pilots recognised and they just decided to go fly through it anyway and I maintain, and I think the evidence proves it, that that was not the case.
They didn't recognise this new developing cell.
They did get into the storm beneath the cell .
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but it was heavy rain, they weren't worried about that.
Then the hammer fell.
It was too late.
(CRACK OF THUNDER) JOHN McCARTHY: It's small.
It's the length of a runway, roughly, and it doesn't last very long so it's something that can happen so quickly that many accidents have occurred because nobody knew it was there.
The storm arrived at the foot of Runway 17 Left virtually unannounced.
But once there, it attracted a lot of attention.
Pilots on the ground as well as trained weather observers saw the worsening storm.
But they all saw it too late to warn the crew of Delta 191.
The storm did show up on a radar screen at the Fort Worth Air Traffic Control Centre.
But at the time of the crash, the meteorologist on duty was in the cafeteria on a meal break.
JOHN McCARTHY: If the flight crew had had any idea that there would be a severe event in front of them they would have missed the approach.
Investigators conclude that the Delta crash was caused by the pilot's decision to continue their approach into the storm - a decision that was made because the crew wasn't warned about the hazard.
In 1985, there were basic systems at airports that could detect dangerous winds but they could not detect a microburst.
On the ground there were systems called Low Level Windshear Alerting Systems that primarily look for differences of wind speed around the airport or on the airport.
Unfortunately, these sensors tend to be spaced so far apart that a microburst could actually exist in between them and escape detection, or at least detection in time to warn a pilot of the threat.
But a microburst detection system to overcome this problem had been developed.
It was being tested in Denver and working very well.
What we found out is our Doppler radar, which is on the ground, is incredibly effective in detecting microbursts and in fact, it can detect about 98% of a microburst.
Conventional radar uses radio waves to measure precipitation inside a storm.
Doppler also sends out radio waves.
But by measuring the frequency of returning waves, Doppler can also calculate the movement of the winds inside a storm.
If you look through the Doppler radar, you see a part of it that's going away from the radar and a part that's coming towards the radar and if it's small, it's absolutely a microburst.
It can be nothing else.
So it has what we call "an unambiguous signature of a microburst", which means we got it.
Since Doppler radar could see a microburst, controllers could use it to warn crews of their presence.
The Denver research resulted in an important new system at airports - Terminal Doppler Weather Radar.
When the system detects dangerous conditions, it relays a warning to air traffic controllers .
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who can then alert pilots.
Flight 236, microburst alert.
After the crash of Delta 191, the Federal Aviation Authority, the FAA, hurried to install Terminal Doppler Weather Radar at high-risk airports.
Dallas Fort Worth was one of the first.
The domes containing the specialised radar are now a common fixture at major airports around the world.
But radar on the ground can't get the warning to the pilots fast enough.
We also have an issue of ground-based systems in that it takes time to communicate the threat to the crew.
The system has to detect it on the ground.
It would typically go to a control position in the control tower and be relayed by voice to the pilot, which can introduce a delay of 10, 15, 20 seconds, which could be very critical.
Planes also needed on-board microburst detection.
A team from NASA began developing such a system by flying into the most dangerous microbursts they could find.
MAN: (OVER TWO-WAY RADIO) Here we go.
- Take it? - Straight ahead.
By risking their own lives, they would eventually save thousands of others.
NARRATOR: The crash of Delta 191 showed that seconds count when planes encounter a microburst.
You're gonna lose it all of a sudden.
There it is.
Increasing alert times Push it up! Way up! .
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could save more lives, especially if a microburst detector was mounted right on the plane.
If you can provide the airplane with 10, 15, 20 seconds of advanced warning, pilots push the throttles up, they build airspeed, they build altitude, they build energy, it's like money in the bank - by the time they get to the microburst, during a recovery, they can survive.
Aviation experts had to find a way to give all pilots those critical 20 seconds.
To develop that technology, they would embark on a high-risk, unprecedented research project.
They would fly a 737 into the most severe microbursts they could find.
We did a very careful risk analysis of all the possible dangers that could occur and initially, you know, the first reaction was, "You want do WHAT with an aeroplane? "You want to fly it through a microburst?" In the summer of 1991, NASA modified a Boeing 737 and went hunting for microbursts.
The idea was to identify on-board technology that could warn pilots of a microburst in their path.
The airborne solution brings detection right into the cockpit so the pilot sees exactly what's in front of the aircraft, and when an alert is given, there's no time delay.
MAN: (OVER TWO-WAY RADIO) Groundspeed 234.
The NASA researchers were testing three separate systems for detecting microbursts.
Modified Doppler radar housed in the 737's nose, a laser radar under its forward cargo bay and a side-mounted infra-red device to measure changes in air temperature.
Each of those systems was wired to banks of computers in the plane's cabin.
A spotter on the ground could find a microburst and quickly direct the plane towards it.
We started with very, very weak microburst.
Again, we had the ground-based radar telling us what we were about to go into, so we started with very weak microburst, gained experience, then gradually worked up to stronger and stronger ones.
You would see the rain begin to fall and you would feel a sinking feeling.
You would be a little settling, a little like an elevator starting down.
So any apprehension that the crew may have had initially about going through them was actually replaced later with joy at finding them.
MAN: Here comes the centre of the target.
Right .
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now.
242 on the groundspeed.
Wind's gone away.
Look for a tailwind.
Watch.
Loss of altitude there too.
There - the wind's gone around the tail at 10 knots.
Good strong down draught in the middle of it.
Just sucked 100ft in almost no time at all.
Saw a good performance decrease too.
We're about 850 and we dropped to 750.
Beautiful.
The project proved that the forward-looking Doppler radar was the only system that could consistently give pilots advanced warnings of a microburst ahead.
What we found was that the Doppler radars could detect an extremely wide variety of microburst.
There's lightning coming out of that one.
If the crew of Delta 191 had a system to warn them of microbursts, they could have boosted power to their engines and started climbing before they encountered it.
That might have given them the speed and the altitude which they sorely lacked when they began their battle with the storm.
The Langley flight tests had, in effect, tamed the microburst menace.
After the NASA tests, the FAA certified a Doppler-based warning system for planes.
Today, forward-looking Doppler radar is standard equipment on commercial flights around the world.
The good news out of all of this tragedy .
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is so many things have now happened, from radar to ground-based systems to airborne systems and especially to training for pilots, we think that microburst accidents are a thing of the past.
JEROME CHANDLER: If there is one crash that we can look back on now and say, "This made things safer because we learned from it," it was Delta 191.
The changes made after the crash of Delta 191 have saved countless lives.
Captain Conners and First Officer Price lost their fight against a microburst but their struggle did manage to expose and disarm an invisible killer.