On August 28, 2001, at 1720 central daylight time, a Swearingen SA226-T, N104BR, piloted by an airline transport pilot, was substantially damaged during takeoff following a loss of directional control on runway 1L (6,700 feet by 100 feet, dry grooved concrete) at the DuPage Airport, West Chicago, Illinois. Visual meteorological conditions prevailed at the time of the accident. The 14 CFR Part 91 business flight was operating on an instrument flight rules flight plan. The pilot and two passengers reported no injuries. The flight was en route to the Springfield-Branson Regional Airport, Springfield, Missouri. The pilot reported, "...At takeoff power, [approximately]. 75KT. On centerline, steering switch had been released at about 60 KT. Aircraft has sudden strong desire to turn left. I applied full [right] rudder and brake, reversed power on both sides. As the left turn continued I applied power to left side. Aircraft left the runway to the left and continued to turn left. I estimate about 500 [feet] from the time I left the center line until aircraft stopped and about a 75 degree change of heading. The nose gear collapsed about 15 [feet] before [aircraft] stopped." "Skid marks from all three gears indicate my recovery started at the center line and continued until leaving the runway. Skid marks show the aircraft in a skidding left turn nose cocked to the right." Using a hydraulic cart and airplane battery power, the nose gear steering was actuated through the application right and left rudder pedal inputs. No anomalies were noted. Examination of the left propeller's start locks revealed one start lock latch damaged and the other two start locks engaged. Two of the right propeller's start locks were not engaged. The right propellar's remaining start lock cam had a witness mark prior to the locking point of the cam. According to the Before Taxi checklist, the propeller start locks are to be in the "RELEASE" position. The flaps and flap control lever were in the 1/2 flap position. There is no performance data in the airplane's flight manual for a takeoff configuration with 1/2 flaps. According to the Before Takeoff checklist, the flaps are to be in the "UP" position. Federal Aviation Regulation 91.103, Preflight action, states, "Each pilot in command shall, before beginning a flight, become familiar with all available information concerning that flight. This information must include ... (b) For any flight, runway lengths at airports of intended use, and the following takeoff and landing distance information: (1) For civil aircraft for which an approved Airplane or Rotorcraft Flight Manual containing takeoff and landing distance data is required, the takeoff and landing distance data contained therein;..." The Federal Aviation Administration and Fairchild Dornier Corporation were parties to the investigation.