On May 28, 1999, at 1015, eastern daylight time, a Cessna 172RG, N9561B, veered off the right side of runway 9C and collided with two runway signs at the Orlando Sanford International Airport in Orlando, Florida. The instructional flight was operated by Comair Aviation Academy under the provisions of Title 14 CFR Part 91 with no flight plan filed. Visual weather conditions prevailed at the time of the accident. The airplane sustained substantial damage, and the commercial pilot was not injured. The flight initially departed Orlando, Florida, at 0730. According to the Director of Training, the pilot was enrolled in an approved flight training program for foreign students, and was conducting solo training as part of that program. The pilot reported that he had received a landing clearance and the landing gear was down and locked. According to the pilot, after touchdown, the airplane began to "shake and tried to turn to the right." The pilot stated that he tried to maintain directional control, but the airplane veered off the right side of the runway into the grass and the collided with two runway signs. The examination of the accident site disclosed that the airplane departed the right side of the runway after landing and struck two runway signs. No mechanical problems with the airplane were reported by the pilot.