On February 20, 2003, about 1720 mountain standard time, a Cessna 172S, N3550X, collided with a hangar while attempting to do a touch-and-go takeoff from runway 21 at the Scottsdale Airport (SDL), Scottsdale, Arizona. Arizona Flight Works operated the rental airplane under the provisions of 14 CFR Part 91. The airplane sustained substantial damage. The student pilot, the sole occupant, received serious injuries. Visual meteorological conditions prevailed for the local area instructional flight, and no flight plan had been filed. The flight departed SDL about 1635, and was scheduled to terminate at SDL. In the pilot's written statement he stated that he had flown 45 minutes in the practice area, and was returning to SDL to perform touch-and-go takeoffs and landings. He contacted SDL tower and received a clearance to perform "touch-and-gos" on runway 21. After landing, he applied full throttle to takeoff; however, the airplane veered abruptly to the left. The student pilot indicated that the airplane's airspeed was "close to, or at, flying speed." He stated that he continued to apply pressure to the right rudder to offset the airplane's leftward direction, with no response. He stated that his attempts to compensate for the airplane's direction of travel were unsuccessful. The airplane struck a runway sign and then a hangar. The pilot did not indicate that he reduced the throttle or attempted to do a takeoff abort at any time during the accident sequence. A Federal Aviation Administration (FAA) inspector interviewed the certified flight instructor (CFI) who stated that the student had about 40 hours of total flight time, and it was the student's third solo flight. The CFI further reported that the day of the accident he had flown the accident airplane with no mechanical anomalies encountered. The FAA inspector examined the airplane and noted no mechanical deficiencies with the airframe directional control, braking, or engine power control systems.