NTSB Factual Report

On June 6, 2002, about 1415 eastern daylight time, a Fairchild Dornier DO-328-300, N413FJ, operated by Atlantic Coast Airlines (ACA) d/b/a Delta Connection flight 6218, was not damaged after the crew reported a loss of flight display information while on approach to Cincinnati/Northern Kentucky International Airport (CVG), Cincinnati, Ohio. The certificated airline transport pilot, commercial rated first officer, flight attendant, and 32 passengers were not injured. An instrument flight rules flight plan was filed for the flight that originated at James M. Cox Dayton International Airport (DAY), Dayton, Ohio, about 1335. Instrument meteorological conditions prevailed for the passenger flight conducted under 14 CFR Part 121.

According to the flight crew, the flight from Dayton to Cincinnati was uneventful until 10 minutes prior to landing. The airplane was being sequenced by air traffic control for an instrument approach when the autopilot disconnected, followed by the loss of the flight director. A few seconds later, the numbers 1, 2, and 3 flight display screens went black for several seconds then came back on line, after which, large red "X's" appeared on the numbers 4 and 5 flight display screens. However, information on all five screens returned to normal after several seconds. When the information on screens number 1, 2 and 3 returned, numerous crew alerting system (CAS) messages were observed on the engine indication and crew alerting system (EICAS). The EICAS also displayed "empty shells" in the engine parameters page, and there was an amber colored "X" in the CAS field.

The captain described the event as similar to the attitude reference heading systems (AHRS) self-test initiated during the start sequence of the airplane.

Also during this event, the master warning horn chimed, the landing gear handle red light illuminated, and the hi-lo tone momentarily sounded.

The airplane landed uneventfully in Cincinnati. In preparation to taxi off the runway, the crew realized that the nose wheel steering was inoperative and there was very little, if any, response from the rudder pedals. The airplane was then towed to the gate. This was the operator's third reported incident regarding a loss of flight displays in flight on this make/model airplane.

Weather reported at CVG, at 1406, included wind from 020 degrees at 7 knots, visibility 10 statute miles, ceiling broken 1,000 feet, overcast 1,500 feet, temperature 63 degrees F, 60 degrees F, and altimeter setting 30.00 inches HG.

The DC Junction box (1VE panel) was removed from and transported to the Barfield Avionics Facility in Miami, Florida for testing. The initial inspection revealed evidence of burning damage on the 1VEC connector and on the BAT1 terminal. The unit was tested with these faults and kept blowing the ground support equipment fuse when attempting to perform the 3PC Current Sensor tests. The damaged parts were replaced and the unit was tested with no discrepancies found.

As a result of the investigation, no failure could be identified that would have caused the loss of flight displays. In addition, the manufacturer reviewed the design of the electrical system and could not identify a design failure.

NTSB Probable Cause

The partial loss of flight displays for undetermined reasons.