What happened
After landing, the captain of Northwest Airlines (NWA) flight 142 received instructions from the Air Traffic Control Tower (ATCT) to taxi toward the gate. The captain reported that taxi speeds were slow due to blowing snow and snow covering the taxiways. The crew stopped on the main taxiway because another aircraft was blocking the path into the ramp area, and ATCT instructed NWA flight 142 to hold their position until the obstruction was cleared.
Simultaneously, the captain of Turkish Airlines flight 6 (THY6) observed NWA flight 142 on the taxiway, noting that the tail of the Northwest aircraft was positioned over the parallel taxiway being used by THY6. The THY6 crew stopped short of the Northwest airplane. Despite the crew expressing an inability to move ahead, ATCT instructed THY6 to continue taxiing. After receiving a second instruction to proceed, the THY6 crew attempted to move around the NWA aircraft but determined they could not pass. While attempting to maneuver, the THY6 aircraft stopped but slid into the tail of the Northwest airplane.
The ATCT ground controller reported that THY6 was taxiing northbound for runway 9R. The controller observed THY6 holding by A10 and restated instructions to proceed. After acknowledging, THY6 continued toward A9, where the aircraft turned and clipped the rudder of the Northwest Airlines DC-9 on Taxiway Bravo.
At the time of the incident, visibility was 1/2 mile with light snow and mist. The runway visual range for runway 14R was reported as 4,000 feet variable 6,000 feet, with winds at 070 degrees at 6 knots.