On August 22, 1997, about 0040 Alaska daylight time, a Fairchild/Swearingen SA227-AC, N27188, collided with an airport tug while taxiing for takeoff, at the Anchorage International Airport, Anchorage, Alaska. The airplane was being operated as an instrument flight rules (IFR) scheduled domestic passenger flight under Title 14 CFR Part 121 when the accident occurred. The airplane, operated by Merlin Express Inc., San Antonio, Texas, as Yute Air Alaska, flight number 421, sustained substantial damage. The captain, first officer, and 5 passengers, were not injured. Visual meteorological conditions prevailed. The operator reported the flight pushed away from gate A-10, and began to taxi toward the departure runway. Adjacent to gate A-12, an airport baggage tug, operated by Omni Support Services, appeared from around the end of the A concourse building. The driver of the tug attempted to stop, but was unable to avoid colliding with the outboard end of the right wing of the airplane. The cab portion of the tug struck the wing, about 4 feet inboard from the tip. The wing sustained crushing, and tearing of the leading edge. The tug driver was uninjured. A Federal Aviation Administration (FAA) airworthiness inspector, Anchorage Flight Standards District Office (FSDO), reported the tug's brakes were ineffective from wet surface conditions or due to a mechanical malfunction. Rain was falling at the time, and the airport ramps were wet. At 0050, an Anchorage International Airport, Aviation Routine Weather Report (METAR) was reporting in part: Wind, 350 degrees (true) at 7 knots; visibility, 7 statute miles in rain; clouds, few at 500 feet, 1,700 feet overcast; temperature, 52 degrees F; dew point, 52 degrees F; altimeter, 29.66 inHg.