Tape: Northwest Airlines pilots dismissed weather warnings
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TODAY IN THE SKY
SIOUX FALLS, S.D. (AP) — Despite being told of high winds and funnel clouds, a Northwest Airlines flight bound for Sioux Falls on June 24 tried to land, even as a twister touched down near the airport, according to weather reports and communications between the plane and tower.
The thunderstorms at Sioux Falls' Joe Foss Field created windshear that made the plane swivel and roll, jostled the passengers and forced the pilots of flight 1462 to pull up and head for Omaha, Neb.
"There was a dark black cloud going all the way to the ground," said Dr. Gary Timmerman of Sioux Falls, one of the passengers seated by a right window, looking west.
"Our right wing got lifted up about 25 feet and it slammed us down, as though someone picked up the end of a table and dropped it. People screamed and then that happened again, and we were still heading down," he said.
That slamming happened several times as the plane descended, said Timmerman, a general surgeon and director of trauma for Sioux Valley Hospital.
At the same time, it felt like someone was holding onto the tail and pushing back and forth "from side to side like in a swivel chair," he said.
It was one of 67 twisters in South Dakota that day, tying a national record for the most in a state in a 24-hour period.
"We don't want to go back through what we just came through," one of the pilots of the DC-9 told the control tower.
"I think we got a nice glance of it," she said of the tornado.
Several earlier flights destined for Joe Foss Field that evening were rerouted to airports around the region.
But the pilots of flight 1462 decided to try to beat the weather.
Even if air traffic controllers clear a plane for landing, the decision to land or go elsewhere lies with the pilots, said David Meyer, air traffic manager in Sioux Falls.
"The final decision for any instruction is the pilot's decision," Meyer said.
Because of southerly winds, flight 1462 was directed to runway 15, which required it to come in from the northwest and land pointing southeast. The flight was scheduled to arrive at 9:45 p.m. but got to Sioux Falls roughly 45 minutes later.
That's about the same time a tornado was documented just north of Interstate 90 and west of Minnesota Avenue, said Greg Harmon, meteorologist in charge of the National Weather Service in Sioux Falls.
That area just north of the airport was hit by thunderstorms from around 8:30 p.m. to after midnight, he said.
"We are confident we had a tornadic touchdown north of the airport," Harmon said of the 10:34 p.m. record.
Northwest flight 1462 had two pilots and three flight attendants onboard. A Northwest spokesman said he did not know out how many passengers were on the flight from Minneapolis because the number was unavailable.
That class of DC-9 has 125 seats and Timmerman said the plane was packed. "I don't think there was an empty seat."
When the pilot did pull out of the wind, the plane was over the airport, though east of the runway, he said.
It felt like the pilot gunned the engines and used one of the updrafts to lift the plane, Timmerman said.
Someone made the comment that the breath of the Lord blew under the wing and got us out of there," he said. "I speculate that had we gone down it would have been into the terminal."
Later, a doctor friend told Timmerman he heard the plane that night: "We heard the plane and we remember thinking, 'What are those fools doing?' They said they could read the writing on the plane."
According to another passenger, Rod Waters of Sioux Falls, one woman "said she was looking down the chimney of a house."
"Rogue windshear"
Edward Davidson, a Northwest pilot and director of flight safety, said all indications are the crew had no idea they would hit such turbulence.
"It's our opinion that we ran into a kind of rogue windshear incident" that Northwest's meteorology department can't explain, he said.
Windshear is a rapid change in wind direction over a very short distance. It's most risky to aircraft during takeoff and landing, when the plane is close to the ground and has little time or altitude to recover.
Before the pilots took off from Minneapolis, they got a briefing from airline forecasters, Davidson said. "We didn't see anything in this packet to lead us or this captain to suggest there were any problems with this flight."
Even after the captain got the report, he called the forecasters again to make sure nothing had changed, Davidson said.
When Flight 1462 neared Sioux Falls, the plane's radar indicated there were no storms within 8 miles of the airport, he said. Northwest requires pilots to avoid the area if storms are within 5 miles, Davidson said.
"So all the weather that he was looking at on his weather radar was well away from the airport," though the pilot did "do some deviations around weather buildups between his location and the airport," he said.
The pilots also got no indication of trouble from air traffic controllers in Sioux Falls, according to Davidson's records.
"For all intents and purposes, the flight could be completed to a landing," he said.
Inbound mesocyclone
But according to an audio recording of communications between the tower and the plane obtained by The Associated Press through the Freedom of Information Act, the pilots were told a storm packing a tornado was fast approaching the airport minutes before the plane got into trouble.
"The weather's moving, you see out there, it's moving towards us from the west, I don't know if you'll beat it in or not," one of the controllers told the pilot around 10:23 p.m.
Less than a minute later the tower radioed the plane to warn of a type of rotating air mass that often produces a tornado.
"Lightning is to the west of us. But I believe the National Weather Service just called us. I don't know what they call it, a quasi mesocyclone, inbound from the southwest," the tower told the plane.
"All right, copy that," the pilot responded.
Harmon said he placed that call about 10:23 p.m. as he and his staff took shelter. The weather service office is at the airport.
"It was close enough that we had to protect ourselves," he said of the "supercell" headed to the airport.
"I told them we had 102 knot (117 mph) incoming winds that were detected at 200 feet off the ground," Harmon said. "I didn't know there was an aircraft on approach."
After Harmon's call to the tower, one of the air traffic controllers told the pilots that if they don't get any response, it means the controllers have left the tower and taken cover themselves.
"That's just a worst case scenario," the controller told the pilot.
"Roger that," she replied.
Once is enough
Around 10:27 p.m., the tower told the pilots of "a wall cloud coming inbound from the west now ... like a line, a wave or something. It's kind of weird."
The pilot responded: "All right."
A minute later, the tower told the plane funnel clouds were moving toward the airport from the west.
Two minutes later, as the air traffic controller flipped the runway lights off and on again to help the pilots see the airport, the controller also warned of windshear.
Another controller reported winds were shifting and gusting to 103 mph just west of the airport and that there was windshear at the runway.
"Copy," the pilot replied.
By about 10:33 p.m., the controllers realized the pilot had pulled up and told her to keep heading southeast and climb to 5,000 feet.
The pilot said something unintelligible and then: "We're going back."
"Did you say you wanted to go back to Minneapolis?" the controller asked.
The pilot responded she doesn't want to try another approach to Sioux Falls nor return to Minneapolis. "We'll take Omaha if we can get that. Right now I want to get to 10,000 (feet) ... and get a plan."
Two minutes later the pilot was heard again: "OK, we're thinking about leveling out at 10,000 and heading over to Omaha if you can get us kind of pointed that way. We don't want to go back through what we just came through."
"Understand that totally. ... Everything looks good between you and Omaha," said the controller, adding that a tornado was reported northwest of the airport.
"Copy. I think we got a nice glance of it," the pilot said.
"Bet you did," the controller replied.
Plane rolled
Davidson said that according to his reports, the plane shifted drastically as its onboard windshear alert system sounded at an altitude of 800 to 1,000 feet as it approached the airport from the northwest.
"As the aircraft made its approach to the airport, it encountered a windshear warning at the same time it got a windshear encounter. The plane rolled to the right and the pilot was able to roll it back to the left again," Davidson said.
"They advanced thrust and did a go-around maneuver. They determined it was unforecast windshear and thought it would be best to move the landing site to Omaha."
Nothing suggests the plane was ever out of control, he said.
"Everything we see on the digital data recorder is that the airplane was fully controllable at all times," Davidson said.
Davidson said 800 feet to 1,000 feet gives the pilot enough altitude to recover but "go-arounds below 500 feet are much more difficult to execute."
Fewer windshear crashes
William Mahoney, of the National Center for Atmospheric Research in Boulder, Colo., agreed, though he believes it was clear the plane had enough forewarning to avoid trouble.
"Any time you're below 1,000 feet you may be at risk," he said of windshear. "When you're below 500 feet you're really in danger. When you're above 500 feet if you're with a skilled pilot and a good aircraft, you probably can recover before you're on the deck."
Most newer, more powerful airplanes can recover from windshear because of better detection equipment and improved pilot training, said Mahoney, who helped develop ground and air detection systems.
For all those reasons, the number of accidents caused by windshear has dropped drastically in the last decade, he said.
"Unless it's a monster event, the aircraft will experience severe turbulence and drop suddenly and get a lot of sideways movement. But if they get a lot of power there's a good chance they'll be able to get out of it," Mahoney said.
It's possible the funnel cloud and not traditional windshear caused the plane to roll on June 24, he said.
"Rotation associated with the tornado vortex could cause a windshear alert," Mahoney said.
A few minutes after the incident, as the plane was headed to Omaha and things had calmed down, the pilot said the tornado was the source of the wind, Timmerman said.
"The pilot came back on and said, 'Needless to say we're not going to try that again. What you felt were windshear forces from a tornado that dropped out of the sky on our right wing,'" he said.
"Threaded the needle"
Mahoney, who has led several Federal Aviation Administration aviation weather projects, said the outcome of Flight 1462 easily could have been different.
"They threaded the needle and they were lucky to get out of there," he said after listening to the taped conversations between the plane and the tower.
"Ten seconds or 15 seconds later this would have been a different story," he said. "For the worse."
Because there were no other planes in the sky, the radio channel was clear of chatter, so the tower and plane had a clear line of communication and air traffic controllers could devote all their time to the flight, Mahoney said.
The controllers also gave the pilots clear and updated information on the storm, he said.
"It was quite surprising that given all this information that they tried to bring this thing in. Thank goodness they were able to execute a missed approach rather than have something else happen," Mahoney said.
It's not unusual for pilots to try to beat storms to the airport or even drop down to see if it's safe to land, he said.
"That happens all over the country every day. But it's a bit unusual to have mesocyclones, the high winds, the descending of tornadoes, and come as close as they did, given the situation that was developing," Mahoney said.
"All the messages are clear that this thing was right on top of them."
Northwest has trained pilots how to handle windshear, its meteorology office is good and the June 24 incident is "not consistent with how they generally operate," Mahoney said.
Despite the incident, the fact that the plane recovered and landed safely is a success story and a credit to good training and better equipment, Mahoney said.
Dr. Timmerman said after the plane landed in Omaha, he went over to the crew to thank them for recovering from the windshear and getting there safely.
One of the pilots didn't talk, but another member of the crew did, he said.
"She was visibly shaken. I didn't talk to her," Timmerman said of the pilot. The other pilot said: "'Doc, that was close.' He gave me a very knowing look and drove off, as though 'Be glad you're alive.' He said that was very close and then just nodded."
No complaints
When the flight arrived in Omaha, passengers cheered, Timmerman said. "It was one of those deals that everyone was so happy to be alive."
Because the College World Series was going on, lodging was hard to come by, though some hotels opened up rooms to the passengers. Because of the bad weather, no other flights were allowed into Sioux Falls that night, so everyone got back the next afternoon on two other planes and a bus, Timmerman said.
He said he has nothing but praise for how the pilots got the plane out of the wind.
"Maybe they got us into it, but they certainly got us out," Timmerman said.
Davidson said no passengers have filed a complaint with the company or the FAA.
"We're left to conclude that it wasn't that hairy of a ride for anybody," he said.
Davidson refused to release the names of the two pilots. But he said the captain is a 20-year veteran with the company and has much experience flying in South Dakota.
As flight 1462 was on its way away from Sioux Falls, the pilot thanked the air traffic controller who guided the plane down.
"You did a great job directing us to the airport, by the way," she said.
"Well thanks .... Hope everything works better going to Omaha," he replied.
The controller then chuckled to another person in the tower: "I don't think we're going to have anyone else come."
--------------------------------------------------------------------------------
Copyright 2003 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.
More airline news
ValuJet in AirTran's past
Blackout left fliers in the dark
Seagulls close Tokyo runway
AA loses pilot dispute
Saudis: No info on airport plot
Jets could survive attack
TODAY IN THE SKY
SIOUX FALLS, S.D. (AP) — Despite being told of high winds and funnel clouds, a Northwest Airlines flight bound for Sioux Falls on June 24 tried to land, even as a twister touched down near the airport, according to weather reports and communications between the plane and tower.
The thunderstorms at Sioux Falls' Joe Foss Field created windshear that made the plane swivel and roll, jostled the passengers and forced the pilots of flight 1462 to pull up and head for Omaha, Neb.
"There was a dark black cloud going all the way to the ground," said Dr. Gary Timmerman of Sioux Falls, one of the passengers seated by a right window, looking west.
"Our right wing got lifted up about 25 feet and it slammed us down, as though someone picked up the end of a table and dropped it. People screamed and then that happened again, and we were still heading down," he said.
That slamming happened several times as the plane descended, said Timmerman, a general surgeon and director of trauma for Sioux Valley Hospital.
At the same time, it felt like someone was holding onto the tail and pushing back and forth "from side to side like in a swivel chair," he said.
It was one of 67 twisters in South Dakota that day, tying a national record for the most in a state in a 24-hour period.
"We don't want to go back through what we just came through," one of the pilots of the DC-9 told the control tower.
"I think we got a nice glance of it," she said of the tornado.
Several earlier flights destined for Joe Foss Field that evening were rerouted to airports around the region.
But the pilots of flight 1462 decided to try to beat the weather.
Even if air traffic controllers clear a plane for landing, the decision to land or go elsewhere lies with the pilots, said David Meyer, air traffic manager in Sioux Falls.
"The final decision for any instruction is the pilot's decision," Meyer said.
Because of southerly winds, flight 1462 was directed to runway 15, which required it to come in from the northwest and land pointing southeast. The flight was scheduled to arrive at 9:45 p.m. but got to Sioux Falls roughly 45 minutes later.
That's about the same time a tornado was documented just north of Interstate 90 and west of Minnesota Avenue, said Greg Harmon, meteorologist in charge of the National Weather Service in Sioux Falls.
That area just north of the airport was hit by thunderstorms from around 8:30 p.m. to after midnight, he said.
"We are confident we had a tornadic touchdown north of the airport," Harmon said of the 10:34 p.m. record.
Northwest flight 1462 had two pilots and three flight attendants onboard. A Northwest spokesman said he did not know out how many passengers were on the flight from Minneapolis because the number was unavailable.
That class of DC-9 has 125 seats and Timmerman said the plane was packed. "I don't think there was an empty seat."
When the pilot did pull out of the wind, the plane was over the airport, though east of the runway, he said.
It felt like the pilot gunned the engines and used one of the updrafts to lift the plane, Timmerman said.
Someone made the comment that the breath of the Lord blew under the wing and got us out of there," he said. "I speculate that had we gone down it would have been into the terminal."
Later, a doctor friend told Timmerman he heard the plane that night: "We heard the plane and we remember thinking, 'What are those fools doing?' They said they could read the writing on the plane."
According to another passenger, Rod Waters of Sioux Falls, one woman "said she was looking down the chimney of a house."
"Rogue windshear"
Edward Davidson, a Northwest pilot and director of flight safety, said all indications are the crew had no idea they would hit such turbulence.
"It's our opinion that we ran into a kind of rogue windshear incident" that Northwest's meteorology department can't explain, he said.
Windshear is a rapid change in wind direction over a very short distance. It's most risky to aircraft during takeoff and landing, when the plane is close to the ground and has little time or altitude to recover.
Before the pilots took off from Minneapolis, they got a briefing from airline forecasters, Davidson said. "We didn't see anything in this packet to lead us or this captain to suggest there were any problems with this flight."
Even after the captain got the report, he called the forecasters again to make sure nothing had changed, Davidson said.
When Flight 1462 neared Sioux Falls, the plane's radar indicated there were no storms within 8 miles of the airport, he said. Northwest requires pilots to avoid the area if storms are within 5 miles, Davidson said.
"So all the weather that he was looking at on his weather radar was well away from the airport," though the pilot did "do some deviations around weather buildups between his location and the airport," he said.
The pilots also got no indication of trouble from air traffic controllers in Sioux Falls, according to Davidson's records.
"For all intents and purposes, the flight could be completed to a landing," he said.
Inbound mesocyclone
But according to an audio recording of communications between the tower and the plane obtained by The Associated Press through the Freedom of Information Act, the pilots were told a storm packing a tornado was fast approaching the airport minutes before the plane got into trouble.
"The weather's moving, you see out there, it's moving towards us from the west, I don't know if you'll beat it in or not," one of the controllers told the pilot around 10:23 p.m.
Less than a minute later the tower radioed the plane to warn of a type of rotating air mass that often produces a tornado.
"Lightning is to the west of us. But I believe the National Weather Service just called us. I don't know what they call it, a quasi mesocyclone, inbound from the southwest," the tower told the plane.
"All right, copy that," the pilot responded.
Harmon said he placed that call about 10:23 p.m. as he and his staff took shelter. The weather service office is at the airport.
"It was close enough that we had to protect ourselves," he said of the "supercell" headed to the airport.
"I told them we had 102 knot (117 mph) incoming winds that were detected at 200 feet off the ground," Harmon said. "I didn't know there was an aircraft on approach."
After Harmon's call to the tower, one of the air traffic controllers told the pilots that if they don't get any response, it means the controllers have left the tower and taken cover themselves.
"That's just a worst case scenario," the controller told the pilot.
"Roger that," she replied.
Once is enough
Around 10:27 p.m., the tower told the pilots of "a wall cloud coming inbound from the west now ... like a line, a wave or something. It's kind of weird."
The pilot responded: "All right."
A minute later, the tower told the plane funnel clouds were moving toward the airport from the west.
Two minutes later, as the air traffic controller flipped the runway lights off and on again to help the pilots see the airport, the controller also warned of windshear.
Another controller reported winds were shifting and gusting to 103 mph just west of the airport and that there was windshear at the runway.
"Copy," the pilot replied.
By about 10:33 p.m., the controllers realized the pilot had pulled up and told her to keep heading southeast and climb to 5,000 feet.
The pilot said something unintelligible and then: "We're going back."
"Did you say you wanted to go back to Minneapolis?" the controller asked.
The pilot responded she doesn't want to try another approach to Sioux Falls nor return to Minneapolis. "We'll take Omaha if we can get that. Right now I want to get to 10,000 (feet) ... and get a plan."
Two minutes later the pilot was heard again: "OK, we're thinking about leveling out at 10,000 and heading over to Omaha if you can get us kind of pointed that way. We don't want to go back through what we just came through."
"Understand that totally. ... Everything looks good between you and Omaha," said the controller, adding that a tornado was reported northwest of the airport.
"Copy. I think we got a nice glance of it," the pilot said.
"Bet you did," the controller replied.
Plane rolled
Davidson said that according to his reports, the plane shifted drastically as its onboard windshear alert system sounded at an altitude of 800 to 1,000 feet as it approached the airport from the northwest.
"As the aircraft made its approach to the airport, it encountered a windshear warning at the same time it got a windshear encounter. The plane rolled to the right and the pilot was able to roll it back to the left again," Davidson said.
"They advanced thrust and did a go-around maneuver. They determined it was unforecast windshear and thought it would be best to move the landing site to Omaha."
Nothing suggests the plane was ever out of control, he said.
"Everything we see on the digital data recorder is that the airplane was fully controllable at all times," Davidson said.
Davidson said 800 feet to 1,000 feet gives the pilot enough altitude to recover but "go-arounds below 500 feet are much more difficult to execute."
Fewer windshear crashes
William Mahoney, of the National Center for Atmospheric Research in Boulder, Colo., agreed, though he believes it was clear the plane had enough forewarning to avoid trouble.
"Any time you're below 1,000 feet you may be at risk," he said of windshear. "When you're below 500 feet you're really in danger. When you're above 500 feet if you're with a skilled pilot and a good aircraft, you probably can recover before you're on the deck."
Most newer, more powerful airplanes can recover from windshear because of better detection equipment and improved pilot training, said Mahoney, who helped develop ground and air detection systems.
For all those reasons, the number of accidents caused by windshear has dropped drastically in the last decade, he said.
"Unless it's a monster event, the aircraft will experience severe turbulence and drop suddenly and get a lot of sideways movement. But if they get a lot of power there's a good chance they'll be able to get out of it," Mahoney said.
It's possible the funnel cloud and not traditional windshear caused the plane to roll on June 24, he said.
"Rotation associated with the tornado vortex could cause a windshear alert," Mahoney said.
A few minutes after the incident, as the plane was headed to Omaha and things had calmed down, the pilot said the tornado was the source of the wind, Timmerman said.
"The pilot came back on and said, 'Needless to say we're not going to try that again. What you felt were windshear forces from a tornado that dropped out of the sky on our right wing,'" he said.
"Threaded the needle"
Mahoney, who has led several Federal Aviation Administration aviation weather projects, said the outcome of Flight 1462 easily could have been different.
"They threaded the needle and they were lucky to get out of there," he said after listening to the taped conversations between the plane and the tower.
"Ten seconds or 15 seconds later this would have been a different story," he said. "For the worse."
Because there were no other planes in the sky, the radio channel was clear of chatter, so the tower and plane had a clear line of communication and air traffic controllers could devote all their time to the flight, Mahoney said.
The controllers also gave the pilots clear and updated information on the storm, he said.
"It was quite surprising that given all this information that they tried to bring this thing in. Thank goodness they were able to execute a missed approach rather than have something else happen," Mahoney said.
It's not unusual for pilots to try to beat storms to the airport or even drop down to see if it's safe to land, he said.
"That happens all over the country every day. But it's a bit unusual to have mesocyclones, the high winds, the descending of tornadoes, and come as close as they did, given the situation that was developing," Mahoney said.
"All the messages are clear that this thing was right on top of them."
Northwest has trained pilots how to handle windshear, its meteorology office is good and the June 24 incident is "not consistent with how they generally operate," Mahoney said.
Despite the incident, the fact that the plane recovered and landed safely is a success story and a credit to good training and better equipment, Mahoney said.
Dr. Timmerman said after the plane landed in Omaha, he went over to the crew to thank them for recovering from the windshear and getting there safely.
One of the pilots didn't talk, but another member of the crew did, he said.
"She was visibly shaken. I didn't talk to her," Timmerman said of the pilot. The other pilot said: "'Doc, that was close.' He gave me a very knowing look and drove off, as though 'Be glad you're alive.' He said that was very close and then just nodded."
No complaints
When the flight arrived in Omaha, passengers cheered, Timmerman said. "It was one of those deals that everyone was so happy to be alive."
Because the College World Series was going on, lodging was hard to come by, though some hotels opened up rooms to the passengers. Because of the bad weather, no other flights were allowed into Sioux Falls that night, so everyone got back the next afternoon on two other planes and a bus, Timmerman said.
He said he has nothing but praise for how the pilots got the plane out of the wind.
"Maybe they got us into it, but they certainly got us out," Timmerman said.
Davidson said no passengers have filed a complaint with the company or the FAA.
"We're left to conclude that it wasn't that hairy of a ride for anybody," he said.
Davidson refused to release the names of the two pilots. But he said the captain is a 20-year veteran with the company and has much experience flying in South Dakota.
As flight 1462 was on its way away from Sioux Falls, the pilot thanked the air traffic controller who guided the plane down.
"You did a great job directing us to the airport, by the way," she said.
"Well thanks .... Hope everything works better going to Omaha," he replied.
The controller then chuckled to another person in the tower: "I don't think we're going to have anyone else come."
--------------------------------------------------------------------------------
Copyright 2003 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.