CHI99LA055

American Eagle, flight 4047, was substantially damaged when it veered off runway 28 and impacted runway lights during touchdown. Night instrument meteorological conditions with a visibility of 1/2 sm in snow and freezing fog prevailed at the time of the accident. Flight 4047 was cleared for the ILS 28 approach and began its descent at a point 1.6 nm inbound from the outer marker. While on the final approach segment, the airplane reached a descent rate of 2,000 fpm and the alerts defining the outer and inner envelopes of the ground proximity warning system sounded. During the descent, the airplane's indicated airspeed varied from 160 knots to 122.8 knots. The flight crew briefed an icing approach speed of 123 knots with the first officer acting as the flying pilot. Fifty-six seconds prior to touchdown, air traffic control (ATC) issued winds 070 degrees at 17 knots with a runway 28 Mu of 82,85,81 and chemically treated thin loose snow over patchy ice. The tailwind component was 14.722 knots. The first officer transferred the flight controls to the captain at approximately 400-500 feet agl. Two seconds prior to touchdown, ATC issued winds 060 degrees at 20 knots. The tailwind component was 15.320 knots. The southern runway lights extending from 2,574 feet - 3,311 feet down the runway were damaged. Flight data recorder information indicated that flight 4047 touched down in a 7 degree left bank attitude. American Eagle had in place 'stabilized approach criteria' to define conditions which required a mandatory missed approach. The American Eagle Aircraft Operating Manual stated that the limiting tailwind component for the airplane was 10 knots. Following the accident, an AE crew chief stated that the #1 MLG tire was peeled off the rim and 'ripped up bad.' He described the #2 MLG tire as having side ways scuff marks on the treaded portion of the tire. He stated that he performed an A/S test and if it was bad that he would have entered it into the minimum equipment list. The aircraft received a ferry permit, after the accident, to be flown to Marquette for repair. The ferry captain reported that he flew the aircraft from TVC to Marquette. Prior to leaving the gate, he tested the antiskid (A/S) system and one of the fault lights came on momentarily in which the captain described the duration as 'just a blink'. The Captain then executed a high speed taxi, braked and then stopped the aircraft. He then tested the A/S light, and no light illuminated. He also reported that there were no problems en route or upon landing at Marquette. He added that there was no fault light illumination during or after landing at Marquette.

History of flight

On December 17, 1998, at 1840 eastern standard time, an Aerospatiale ATR42-300, N47AE, operated by American Eagle Airlines, Incorporated, as flight 4047, received substantial damage during landing on runway 28 (6,501 feet by 150 feet, asphalt/snow) at Cherry Capital Airport (TVC), Traverse City, Michigan. Night instrument meteorological conditions prevailed at the time of the accident. The 14 CFR Part 121 passenger carrying flight was operating on an instrument flight rules (IFR) flight plan. The 3 flight crew members and 40 passengers reported no injuries. The flight originated at Chicago O' Hare International Airport, Chicago, Illinois, at 1730, and was en route to its scheduled destination of TVC. Austin Straubel International Airport (GRB), Greenbay, Wisconsin was filed as an alternate airport.

During the flight, the captain was acting as the non flying pilot (NFP) and the first officer was the flying pilot.

At 1813:40, radar data indicates that the aircraft is approximately 65 nmi southwest of TVC at 15,000 feet msl. At 1813:40, the cockpit voice recorder indicates that the captain said, "information Lima, two two five six zulu. winds are three two zero at ten. two and a half, light snow, mist. ... one thousand scattered, three thousand broken, fifty five hundred broken, minus two, minus four, two niner niner four is already set left center. they're using the ILS to two eight. thin patchy, ice. sanding and chemicals are in progress. ... landing's gonna be, thirty five thousand pound landing with icing speeds... call it one twenty three, one twenty three squared.

In the Federal Aviation Administration's (FAA's) Air Traffic Control report of the aircraft accident, Minneapolis Air Route Traffic Control Center (ARTCC) told flight 4047 they were number two following a Cessna 152. Flight 4047 was then issued instructions to fly heading 300 to join the localizer with discretion to descend to 2,700 feet msl. Approximately three minutes later, ARTCC instructed flight 4047 to join the localizer for runway 28 and proceed inbound and to expect approach clearance after the Cessna 152 was on the ground. At 1837:53, the CAPT said, "...there's GWENN right there...". At 1838:28 Minneapolis Center cleared Flight 4047 for the ILS 28 approach at TVC and was instructed to maintain two thousand seven hundred feet until on a published portion of the approach.

Radar data indicates that the aircraft maintained an altitude of 2,700 feet msl until it was 1.6 nmi inbound from the outer marker, on the ILS 28 approach. Thirty six seconds later, the aircraft was at 1,500 feet msl and 3.3 nmi inbound from the outer marker.

At 1839:00 the cockpit audio mike recorded, "sink rate, sink rate, sink rate" followed by, "whoop whoop, pull up, whoop whoop, pull up, whoop whoop, pull up" at 1839:04. Five seconds later, the first officer called for 30 degrees of flaps.

At 1839:30 the TVC tower controller transmitted, "Eagle flight forty seven Tranverse City runway two eight. cleared to land. wind zero seven zero at one seven. altimeter's two niner niner five. ... runway two eight Mu is eight two eight five eight one, with chemically treated thin loose snow over patchy ice." (See Test and Research section for tailwind and crosswind components)

At 1839:44 a transmission from the accident aircraft responded, "cleared to land, Eagle forty seven."

At 1840:24 the TCV tower controller transmitted, "wind zero six zero at two zero." (See Test and Research section for tailwind and crosswind components)

At 1840:26 the cockpit audio mike recorded a "sound similar to aircraft touching down on runway".

In a debrief taken by American Eagle, Incorporated, on December 18, 1998, the captain reported:

"On approach to Traverse City we received a notice of weather change. This was approximately at the outer marker and made by the tower. The tower advised us of the change in direction and velocity of the wind. At approximately three to five hundred feet the first officer positively transferred control of the aircraft to me. I confirmed positive transfer of controls. The approach was stable. At touchdown the aircraft veered to the left. I returned the aircraft to the centerline and then continued to the gate. The passengers deplaned by jetbridge. Upon postflight inspection damage to the aircraft was noted. I then contacted the company."

In a debrief taken by American Eagle Airlines, Incorporated, on December 18, 1998, the first officer reported:

"I was flying an ILS 28 to TVC. At approximately the outer marker there was a reported wind change. I flew the approach normally. At approximately 400-500 feet agl, control of the aircraft was transferred to the captain. We continued visually upon touchdown the aircraft veered left. The captain brought the aircraft back to the centerline and a normal taxi to the gate was accomplished. Upon postflight of aircraft, aircraft damage was discovered. To my knowledge the captain contacted the company."

During a postaccident interview, the captain stated that he was inbound from Ft. Wayne on another flight, swapped aircraft in Chicago, obtained weather and greeted the first officer at the gate. He reported that he reviewed the weather packet and maintenance logs, which did not have any open write ups. He described the takeoff, flight and approach as normal into Traverse City, Michigan. He obtained information Lima and was vectored and subsequently cleared for the ILS 28 approach. He stated that the winds were reported as 030 at 17 knots, the crosswind component chart was pulled out on approach. He stated he was visual at 800 feet, and at approximately 500 feet, the first officer indicated to him that he [first officer] wanted to transfer control. He also stated that there was a positive transfer of control. He stated that shortly after touchdown, the aircraft veered to the left and that he could not see the centerline. He stated that there were "windrows" of snow 10-15 feet from the edge of the runway. The captain added that he believed that he applied toe brakes shortly after touchdown and applied some reverse. He also added that he could not remember if the aircraft began to veer before or after braking. He added that shortly after all three gear on the aircraft touched down, the aircraft veered to the left. The captain stated that he had applied aileron control into the wind with slightly forward pressure. He reported that he did not notice an anti skid fault.

During a postaccident interview, the first officer stated that it felt like a normal touchdown but that the nose went left. There was a "windrow" of snow 10 feet from the edge of the runway. He stated that the captain hit the windrow and taxied back out. The first officer stated that he was not touching any of the flight controls during the landing. He stated that the approach speed was 125-130 knots and bugged for icing speeds. He stated that the captain had given the ATIS information. The first officer stated that prior to the outer marker the winds were reported as 030 at 17 knots and visibility went to 1/2 mile. He stated that they discussed that it would be a crosswind and calculated the crosswind component with the tailwind component. The first officer stated that he transferred control since he did not feel comfortable landing the aircraft after seeing the snow covered runway.

Other damage

The TVC Airport Operations Manager reported that runway lights 12, 13, 14, 15, and 16, located on the south side of runway 28, were "knocked down". The "knocked down" lights were between taxiway H and the approach end of runway 23. The location of light 12 was reported to be 2,574 feet from the threshold of runway 28. The distances between lights 12, 13, 14, 15, and 16 were reported to be 184 feet, 185 feet, 184 feet and 184 feet respectively.

Personnel information

The captain, age 41, was hi