Scientists Seek to Solve Deadly Wind Shear Mystery
Aug. 18, 1985
OLIVE BRANCH, Miss. (AP) _ Using an advanced radar system and an array of computers, meteorologists and technicians working here are peering into the heart of storms - and even flying into them - to solve the mystery of the deadly wind shear which slaps planes from the sky.
The goal of the research is to build a warning device that can spot developing wind shear conditions, said Ronald E. Rinehart, head of the field team from Lincoln Laboratories of Lexington, Mass.
''The idea is to develop a system that will get the information to the pilots in time for them to do something about it,'' he said.
Lincoln, a research arm of Massachusetts Institute of Technology, is conducting the wind shear study for the Federal Aviation Administration. Another team from the University of North Dakota has set up a cooperative study about five miles away.
Wind shear has been blamed for dozens of major airline crashes, including an accident that killed 154 people near New Orleans on July 9, 1982.
A form of wind shear, known as a microburst, is suspected as the cause of the crash of a Delta Airlines Lockheed L-1011 in Dallas on Aug. 2.
Microbursts occur in or near rainstorms as a column of air strikes the ground.
''It's been compared to pointing a garden hose straight down,'' Rinehart said. ''Only the air, instead of going into the ground, strikes the earth and sprays outward in all directions.''
The resulting sudden shift in wind can throw large planes out of control at a time when they are most vulnerable - takeoff and landing. Scientists say smaller planes are less vulnerable because they enter the wind shear area at slower speeds and thus have more time to adjust to the changed conditions.
Inside a series of trailers and other temporary structures, researchers aim their radar beam at rainstorms and study a trio of colorful displays depicting precipitation, wind velocity and turbulence.
By varying the sweep and elevation of the radar antenna, the scientists can collect data on different parts of a storm as it develops and then decays.
Several times last week, a specially equipped Cessna Citation, operated by the University of North Dakota in a companion study, flew through the clouds to collect information on temperature, size of raindrops, winds, icing conditions and turbulence.
At one point, Rinehart and his team spotted a developing microburst and guided the jet into the area.
''I was surprised that he (the pilot) went into it, but he did,'' Rinehart said. ''There was about a 50-knot downdraft and he lost about 500 feet in just seconds.''
Don Burrows, the flight scientist aboard the Citation, said the trip through the microburst was not boring.
''We kind of leave it up to the pilot to decide whether to go into something like that,'' Burrows said. ''We could tell that we were in a microburst - it got pretty rough.''
Rinehart estimates the radar system the researchers hope to develop could be ready for installation at airports in four or five years.