Midair scare as 777's windshield cracks

Found in the International Herarld Tribune.

WASHINGTON Alitalia Flight 610 was over the Atlantic en route to New York from Rome last July when the Boeing 777 seemed to shudder. Passengers smelled smoke.
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The cabin crew ran up to the flight deck as passengers screamed, said Bruce Northrup, a New York City banker returning from a wedding with his wife and 15-year-old son.
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“People were yelling, ‘Tell us what’s going on,'” he said. The twin-engine jet made a U-turn and began descending gradually. The pilot told the 300 or so frightened passengers that they had a “serious technical problem” and were headed to Shannon, Ireland, a half-hour away. He also told them to calm down.
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They were quiet, but not calm, for what turned into a very long 90 minutes, Northrup said. After a safe emergency landing, passengers saw what had caused the problem: a windshield covered with cracks.
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“That window looked like something out of an automobile junkyard,” Northrup said. Boeing officials traced the problem to faulty wiring in a window heater. At least two other Boeing 777’s have experienced the same problem in the past year. All landed safely and no one was hurt.
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Experts say three similar incidents in one year is unusual for an aircraft.
.
The 777, Boeing’s newest, largest twin-engine jet, entered service in 1995. There are 138 registered 777’s in the United States, according to Federal Aviation Administration records.
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The windshields of 777’s, made of three layers of glass, acrylic and epoxy, can get brittle in the cold, thin air at cruising altitude, and are warmed by a heater to stay elastic. The wires on the three planes that suffered cracked windshields loosened and shorted out.
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On the Alitalia flight, the short caused a small fire and the innermost layer of the window cracked, Liz Verdier, a Boeing spokeswoman, said. The flight crew put out the fire with an extinguisher and then brought the plane down to 10,000 feet, about 3,000 meters. That reduced the difference between the pressurized cockpit and the thin air outside, said Bill Waldock, aviation safety professor at Embry-Riddle Aeronautical University in Arizona. The danger at high altitudes is that the windshield could shatter and loose items or people could be sucked out, although that has never happened on a commercial flight.
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Boeing has sent a directive to airlines instructing them how to tighten the wire connections. Boeing also is developing circuit breakers that will prevent sparking and the window from overheating, Verdier said.
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Fires can be a bigger safety issue than cracked windows. But John O’Brien, safety director for the Air Line Pilots Association, said the wiring problem in the 777’s was not a major concern because the embedded filaments in the windshield were isolated from other combustible materials.
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Officials of the Federal Aviation Administration said that Boeing was taking appropriate action. “Anytime there’s a fire, there’s a concern to us,” said Paul Takemoto, a spokesman for the aviation agency. “But cracked windshields rarely affect the safety of the aircraft.”
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Waldock said to his knowledge the most serious incident involving a windshield occurred 13 years ago over England when the captain’s front panel of a British Airways BAC-111 cracked and blew out as the plane was cruising at 23,000 feet.
.
“He started out of the airliner,” Waldock said of the pilot. A member of the flight crew managed to grab his legs, and three stewards clung to him for 15 minutes while the copilot made an emergency landing. “They landed with him out the front end,” Waldock said.
.WASHINGTON Alitalia Flight 610 was over the Atlantic en route to New York from Rome last July when the Boeing 777 seemed to shudder. Passengers smelled smoke.
.
The cabin crew ran up to the flight deck as passengers screamed, said Bruce Northrup, a New York City banker returning from a wedding with his wife and 15-year-old son.
.
“People were yelling, ‘Tell us what’s going on,'” he said. The twin-engine jet made a U-turn and began descending gradually. The pilot told the 300 or so frightened passengers that they had a “serious technical problem” and were headed to Shannon, Ireland, a half-hour away. He also told them to calm down.
.
They were quiet, but not calm, for what turned into a very long 90 minutes, Northrup said. After a safe emergency landing, passengers saw what had caused the problem: a windshield covered with cracks.
.
“That window looked like something out of an automobile junkyard,” Northrup said. Boeing officials traced the problem to faulty wiring in a window heater. At least two other Boeing 777’s have experienced the same problem in the past year. All landed safely and no one was hurt.
.
Experts say three similar incidents in one year is unusual for an aircraft.
.
The 777, Boeing’s newest, largest twin-engine jet, entered service in 1995. There are 138 registered 777’s in the United States, according to Federal Aviation Administration records.
.
The windshields of 777’s, made of three layers of glass, acrylic and epoxy, can get brittle in the cold, thin air at cruising altitude, and are warmed by a heater to stay elastic. The wires on the three planes that suffered cracked windshields loosened and shorted out.
.
On the Alitalia flight, the short caused a small fire and the innermost layer of the window cracked, Liz Verdier, a Boeing spokeswoman, said. The flight crew put out the fire with an extinguisher and then brought the plane down to 10,000 feet, about 3,000 meters. That reduced the difference between the pressurized cockpit and the thin air outside, said Bill Waldock, aviation safety professor at Embry-Riddle Aeronautical University in Arizona. The danger at high altitudes is that the windshield could shatter and loose items or people could be sucked out, although that has never happened on a commercial flight.
.
Boeing has sent a directive to airlines instructing them how to tighten the wire connections. Boeing also is developing circuit breakers that will prevent sparking and the window from overheating, Verdier said.
.
Fires can be a bigger safety issue than cracked windows. But John O’Brien, safety director for the Air Line Pilots Association, said the wiring problem in the 777’s was not a major concern because the embedded filaments in the windshield were isolated from other combustible materials.
.
Officials of the Federal Aviation Administration said that Boeing was taking appropriate action. “Anytime there’s a fire, there’s a concern to us,” said Paul Takemoto, a spokesman for the aviation agency. “But cracked windshields rarely affect the safety of the aircraft.”
.
Waldock said to his knowledge the most serious incident involving a windshield occurred 13 years ago over England when the captain’s front panel of a British Airways BAC-111 cracked and blew out as the plane was cruising at 23,000 feet.
.
“He started out of the airliner,” Waldock said of the pilot. A member of the flight crew managed to grab his legs, and three stewards clung to him for 15 minutes while the copilot made an emergency landing. “They landed with him out the front end,” Waldock said.
.WASHINGTON Alitalia Flight 610 was over the Atlantic en route to New York from Rome last July when the Boeing 777 seemed to shudder. Passengers smelled smoke.
.
The cabin crew ran up to the flight deck as passengers screamed, said Bruce Northrup, a New York City banker returning from a wedding with his wife and 15-year-old son.
.
“People were yelling, ‘Tell us what’s going on,'” he said. The twin-engine jet made a U-turn and began descending gradually. The pilot told the 300 or so frightened passengers that they had a “serious technical problem” and were headed to Shannon, Ireland, a half-hour away. He also told them to calm down.
.
They were quiet, but not calm, for what turned into a very long 90 minutes, Northrup said. After a safe emergency landing, passengers saw what had caused the problem: a windshield covered with cracks.
.
“That window looked like something out of an automobile junkyard,” Northrup said. Boeing officials traced the problem to faulty wiring in a window heater. At least two other Boeing 777’s have experienced the same problem in the past year. All landed safely and no one was hurt.
.
Experts say three similar incidents in one year is unusual for an aircraft.
.
The 777, Boeing’s newest, largest twin-engine jet, entered service in 1995. There are 138 registered 777’s in the United States, according to Federal Aviation Administration records.
.
The windshields of 777’s, made of three layers of glass, acrylic and epoxy, can get brittle in the cold, thin air at cruising altitude, and are warmed by a heater to stay elastic. The wires on the three planes that suffered cracked windshields loosened and shorted out.
.
On the Alitalia flight, the short caused a small fire and the innermost layer of the window cracked, Liz Verdier, a Boeing spokeswoman, said. The flight crew put out the fire with an extinguisher and then brought the plane down to 10,000 feet, about 3,000 meters. That reduced the difference between the pressurized cockpit and the thin air outside, said Bill Waldock, aviation safety professor at Embry-Riddle Aeronautical University in Arizona. The danger at high altitudes is that the windshield could shatter and loose items or people could be sucked out, although that has never happened on a commercial flight.
.
Boeing has sent a directive to airlines instructing them how to tighten the wire connections. Boeing also is developing circuit breakers that will prevent sparking and the window from overheating, Verdier said.
.
Fires can be a bigger safety issue than cracked windows. But John O’Brien, safety director for the Air Line Pilots Association, said the wiring problem in the 777’s was not a major concern because the embedded filaments in the windshield were isolated from other combustible materials.
.
Officials of the Federal Aviation Administration said that Boeing was taking appropriate action. “Anytime there’s a fire, there’s a concern to us,” said Paul Takemoto, a spokesman for the aviation agency. “But cracked windshields rarely affect the safety of the aircraft.”
.
Waldock said to his knowledge the most serious incident involving a windshield occurred 13 years ago over England when the captain’s front panel of a British Airways BAC-111 cracked and blew out as the plane was cruising at 23,000 feet.
.
“He started out of the airliner,” Waldock said of the pilot. A member of the flight crew managed to grab his legs, and three stewards clung to him for 15 minutes while the copilot made an emergency landing. “They landed with him out the front end,” Waldock said.
.