Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: WEDNESDAY, July 6, 1994 TAG: 9407060064
SECTION: NATIONAL/INTERNATIONAL PAGE: A-1 EDITION: METRO
SOURCE: From The New York Times and The Associated Press
DATELINE: CHARLOTTE, N.C. LENGTH: Medium
Airport sensors indicate the USAir DC-9 flew into torrential rains and heavy gusting headwinds that almost doubled in the last minute it was in the air, leading the pilot to abort the landing when the plane was 150 feet above the ground.
The captain and first officer who survived told investigators Tuesday that they tried to avoid storm pockets as they landed and did not hear an on-board alarm warning of dangerous wind shear.
Capt. Michael R. Greenlee and First Officer James Hayes were ``cooperative and very helpful'' in separate interviews with National Transportation Safety Board investigators, said John Hammerschmidt, a board member.
The pilots said they noticed a concentration of storms to the south and east of Charlotte-Douglas International Airport as they descended toward landing. "They agreed they would turn right, which is west, to stay away from those cells,'' Hammerschmidt said.
Investigators can put together an almost second-by-second account of Flight 1016's disastrous last two minutes as it roared into a storm, tried to abort its landing and climb back into the air, then crashed to earth, killing 37 people and injuring 20 others.
Investigators Tuesday pulled a final body from the wreckage of the plane's tail. The discovery did not change the death toll.
The investigation will probably take from nine to 12 months.
Wind shear is a sudden shift in wind speed and direction due to a rapid downward rush of cooled air. Pilots are taught to fly through it essentially by going into a takeoff attitude with the nose up and as much power as possible.
But wind shear during a landing can be disastrous, because the wheels and flaps are down, producing drag. Sometimes not even engines at full throttle can accelerate the plane quickly enough to keep it airborne.
The pilots said Hayes gave the engines maximum power, turned right and turned the nose up.
The plane climbed to 350 feet, but the pilots ``felt a severe sink rate,'' which would be expected if they encountered a wind shear, Hammerschmidt said.
``Neither pilot recalled hearing the on-board windshear alert activated.'' Hammerschmidt said. It is almost certain that the severe weather played a role in the accident.
Just before 6:40 p.m., as Flight 1016 was about five miles from the airport and about 1,650 feet above the ground, its crew asked for a condition report from the pilot about to land ahead of them. The plane ahead radioed that conditions were smooth.
At 6:40:50, Flight 1016 was told the wind was at a 100-degree angle and 19 knots. Flights are not permitted to land in crosswinds exceeding 30 knots. Fifteen seconds later, the control tower issued a wind shear alert, saying the wind had shifted to 190 degrees and 13 knots. The alert means only that conditions exist that could produce wind shears.
Just before 6:42 p.m., the flight was six-tenths of a mile from the runway and 250 feet above the ground. About this time - it is impossible to pinpoint when - a light rain turned to a torrential downpour with fierce gusts.
Airport sensors indicate the plane flew into gusting headwinds that increased from 21 knots to 35 knots, almost 40 mph, in about a minute.
By 6:42 p.m., Flight 1016 was four-tenths of a mile from the runway, 150 feet off the ground. About that time, the pilot decided to abort the landing. Radar data show him veering to the right - westward - at seven seconds after 6:42. Four seconds later the plane had climbed from 150 to 350 feet. At 13 seconds after 6:42, the plane radioed that it was ``on the go,'' meaning it was circling to abort its landing. Nine seconds later, the pilot radioed that he was turning to the right. Radar tracked the plane at 350 feet above the ground and two-tenths of a mile west of the runway at 16 seconds after 6:42.
But rather than climbing, the plane suddenly dropped. In four seconds, it fell from 350 feet to 150 feet. It plummeted to earth less than five seconds later.
Among the issues highlighted by the crash is the development of wind shear detection devices. Nine airports in the United States have newly developed Doppler Radar systems, which are far more advanced than the older system used at Charlotte and most airports. Charlotte is supposed to get one of the $2.5 million systems next year.
Roanoke Regional Airport is not on a list of 47 sites that have received or are scheduled to receive the Terminal Doppler Weather Radar system.
Keywords:
FATALITY
by CNB