ABSOLUTELY CONFIRMED!!!! 5 flights with the CRJ700. 5 times, I have the FMS set as DIR----> Menbo. FMS source is FMS1. On direct heading and on the white line. Select "Nav" switch and autopilot immediately commands a left turn. Plane just turns to the left through 270 degrees of turn Until I take over and, using heading hold or hand flying, manually send the aircraft toward Menbo. This aircraft is grounded until this is sorted out.