On July 5, 1994, about 0810 eastern daylight time, N901VJ, a Mconnell Douglas DC-9-32 operated by Valujet Airlines encountered turbulence during climb to cruise over Valdosta, Georgia, The flight was operating as flight No. 109, a 14 CFR Part 121, scheduled, domestic, passenger service from Atlanta, Georgia to Orlando, Florida. Instrument meteorological conditions prevailed at the time and an IFR flight plan was filed. The airplane was not damaged and one flight attendant received serious injuries. The rest of the crew and passengers received no injuries. The flight originated about 25 minutes earlier. The crew reported that during climb at flight level 180 they encountered turbulence that they described as "moderate chop" and then illuminated the seatbelt sign and made an announcement for the passengers to remain seated. They also instructed the cabin attendants that they could initiate cabin service. One flight attendant in the rear galley area suffered multiple fractures of the right lower leg. The flight continued to Orlando, Florida, where the flight attendant was evacuated to a local hospital. A review of the available meteorological data was conducted and no evidence of thunderstorms, or convective activity in the vicinity of the flight that would have appeared on airborne weather radar was noted. The DFDR was removed and transported to the NTSB laboratory for readout. The readout indicated the airplane experienced a "G" excursion of minus .4 to plus 2.4 "Gs".