Date: 201402
Local time of day: 1801-2400
Location: EWR.Airport, NJ
Flight conditions: VMC
Weather elements / visibility: Rain; Snow; Windshear; Icing
Light: Night
Aircraft: Medium Transport; Low Wing; 2 Turbojet Eng
Operator: Air Carrier
Operating under: Part 121
Mission: Ferry / Re-Positioning
Flight phase: Taxi
ATC / advisory: Ground EWR
Reporter organization: Air Carrier
Reporter function: Pilot Flying; Captain
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Situational Awareness
Second reporter function: First Officer; Pilot Not Flying
Anomaly: Ground Event / Encounter Loss Of Aircraft Control
Detector: Person Flight Crew
When detected: Taxi
Result: Air Traffic Control Provided Assistance; Flight Crew Took Evasive Action; Flight Crew Requested ATC Assistance / Clarification; General Maintenance Action
Contributing factors: Airport; Procedure; Weather
Primary problem: Ambiguous

Narrative: After landing on Runway 4R and taxiing across 4L on Taxiway J; we contacted Ground for further taxi instructions. Ground asked if we could still make a hard left onto Taxiway R. I immediately began a left turn and the First Officer responded that we could. As the aircraft began to turn the nosewheel began to slide on the ice covered taxiway. This resulted in a wider than normal turn radius and caused us to taxi over a patch of unplowed snow in the intersection of J and R. The snow was about 5 inches deep and looked to be soft enough to continue. As the aircraft continued the turn it became clear that there were hard ice blocks under the top layer of new snow. The aircraft came to a stop (while still on taxiway J and R) and; not wanting to cause any damage to the aircraft by powering out; I called Ground and explained that we would need assistance to continue. I set the parking break and we waited for the Port Authority to arrive and plow; shovel and deice the area around us. A tug was called and eventually we were pulled out of the snow.The taxiways were plowed; however; not to the entire width. This resulted; especially in intersections; in unplowed areas in the corners. Due to several snow storms in the weeks prior; there were hard ice blocks under the fresh new snow. The plowed portions of the taxiways were very icy; in fact; upon exiting Runway 4R I told Tower that the breaking action was poor on the high-speed taxiway. Since we were a ferry flight the aircraft was extremely light which did not help with traction. Clearly my error was to attempt a sharp turn under those conditions.The error was mine alone. Under very tricky taxiing conditions in a light aircraft I should not have attempted a maneuver that is normally done. Even though the aircraft never left a taxiway; I should be more wary of going over any snow covered areas.


Second narrative: The aircraft continued to slide into about 3-5 inches of unplowed snow on the Taxiway (R). The Captain came to a complete stop on Taxiway R and told Ground that we would need some assistance. We were able to get help from the Port Authority by salting; removing unplowed snow and putting sand on the ground to allow the tug to take us out of the snow; then after the super tug came and towed the aircraft to Terminal A. Maintenance was there to also assist us as well.Because of the quick action of the Captain the aircraft was able to come to a complete stop on the taxiway which prevents any visual damage to the aircraft.


Synopsis: After landing on EWR Runway 4R and crossing 4L; the crew attempted to transition from Taxiway J to R but slid off the taxiway. The aircraft was towed to the gate after authorities cleared the obstructing ice and snow.