On February 16, 2003, at 1723 central standard time, a Swearingen SA-26AT, N30TF, experienced a nose gear separation following a loss of directional control while landing on runway 30L (6,997 feet by 100 feet, asphalt) at the St. Louis Downtown Airport, Cahokia, Illinois. The pilot was not injured. The airplane was substantially damaged. The 14 CFR Part 91 flight was operating in instrument meteorological conditions, and an IFR flight plan was filed. The flight originated from Indianapolis, Indiana, at 1600. The pilot reported the automatic terminal information service (ATIS) was reporting the wind as being from 010 degrees at 14 knots, gusting to 21 knots. He reported that prior to landing, he was informed by the tower that the braking action was fair. The pilot reported that during the landing roll, at a speed of about 30 miles per hour, the airplane began drifting to the left. He stated that he attempted to correct the drift using nose wheel steering, right rudder, and right brake, to no avail. He reported the thick ice and snow on the left side of the runway pulled the airplane further to the left. The airplane departed the left side of the runway where it came to rest on its nose. The nose gear had separated from the airplane and according to the pilot, it was located approximately 20 feet behind the airplane. Friction testing on runway 30L performed approximately 46 minutes prior to the accident produced readings of 34%g, 36%g, and 33%g on various sections of the runway. According to International Civil Aviation Organization (ICAO) definitions, these readings place the braking action in the medium range. An annotation written on the Airfield Friction paperwork stated, "1/2 inch loosely packed wet snow at all 3 locations."