On October 3, 1998, about 2300 eastern daylight time, a Mooney M20J, registered to Flight Express, Inc., operated by Flight, Inc., collided with a parked airplane while taxiing after landing at the Orlando Executive Airport, Orlando, Florida. Visual meteorological conditions prevailed at the time and no flight plan was filed for the 14 CFR Part 91 personal flight. The airplane was substantially damaged and the commercial-rated pilot, and one passenger were not injured. The flight originated about 2215 from the Lakeland Linder Regional Airport, Lakeland, Florida. The pilot stated that he first noticed that the landing light was inoperative while taxiing after sunset to takeoff for the first leg of the planned two-leg cross-country flight. The first leg of the flight was uneventful. Due to the time of day, maintenance was unavailable there and he elected to depart for the final leg of the flight where an uneventful landing occurred. While taxiing toward the ramp at a rate of about 5 miles per hour, he reported that the windows fogged up due to rain and the area that he was taxiing, contained no lighting. He noted the silohouette of a helicopter to his left and while taxiing to avoid the helicopter, he felt a bump, then a slow impact, followed by the immediate stopping of the engine. Both he and the passenger exited the airplane, recognized what had happened, and contacted the tower. He further reported that the airport police arrived about 2-3 minutes later. Examination of the accident site revealed that the right wing of the Mooney airplane collided with the left wing of an airplane which was parked on a nonmovement area. Examination of the markings on the taxiway to taxilane near the north ramp area was performed by a program manager of the Orlando Airports District Office. The taxilane object-free area was measured and found to be 41 feet either side of the taxiway centerline, which for the accident airplane would allow for 23.5 feet clearance. The distance from the taxilane centerline to the edge of the pavement where the helicopter was parked was found to be 59 feet. The taxilane markings leading into the north ramp area makes a slight deviation to the left to avoid the tie down spaces for parked airplanes on the nonment area.