Introduction
A pilot reported an accident that occurred during takeoff in snow conditions. The event resulted in substantial damage to the airplane and was attributed to the pilot's failure to properly deice the aircraft before departure.
Narrative
During the preflight inspection, it was snowing, and the pilot wiped accumulated snow off the wings "as best as [he] could." While taxiing to the runway, the pilot noted that snow was falling heavily and observed a light accumulation of wet snow on the wings. As the airplane accelerated during the takeoff roll, the pilot saw snow "sloughing off" the wings.
After becoming airborne, while climbing to about 150 feet above ground level, the airplane yawed to the left. The pilot attempted to counteract the yaw by applying right aileron. He reported that he "could see a stall forming," so he lowered the nose and reduced engine power to idle. The airplane subsequently impacted the general aviation ramp in a left-wing-down attitude and slid an estimated 500 to 600 feet.
Pilot Report and Damage
On the National Transportation Safety Board Aircraft Accident/Incident Report form, the pilot stated that the airplane stalled and recommended "better deicing" before takeoff. The airplane sustained substantial damage to the fuselage and left wing. The pilot reported no preaccident mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation.
Weather and Runway Information
A review of recorded data from the automated weather observation station located on the airport showed that approximately 27 minutes before the accident, the wind was from 010° at 8 knots, visibility was 1/2 mile with moderate snow and freezing fog, and the sky was broken at 500 feet above ground level and overcast at 1,500 feet. The airplane departed from runway 16.
Regulatory Guidance
The Federal Aviation Administration (FAA) Aeronautical Information Manual states that "The presence of aircraft airframe icing during takeoff, typically caused by improper or no deicing of the aircraft being accomplished prior to flight has contributed to many recent accidents in turbine aircraft." It further advises ensuring that lift-generating surfaces are completely free of contamination before flight, preferably through a tactile check. The FAA Advisory Circular AC 135-17 notes that ice, snow, or frost formations as thin as medium or coarse sandpaper can reduce wing lift by up to 30 percent and increase drag by 40 percent.
A service bulletin from the airplane manufacturer, included in the public docket, describes deicing and anti-icing ground procedures. It emphasizes the "Clean Aircraft Concept," stating that takeoff should not be attempted when ice, snow, slush, or frost is present or adhering to critical surfaces, as any deposit may drastically affect performance due to reduced aerodynamic lift and increased drag.