EMB ERJ 170/175 ER/LR
Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Situational Awareness
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter CFTT / CFIT
Air Traffic Control Issued New Clearance; Flight Crew Became Reoriented; Flight Crew Took Evasive Action
Aircraft; Human Factors; Procedure
We were cleared to depart MFR on the Jackson 1 departure from Runway 14. This involves a climb on runway heading to 1800 feet; a right turn to heading 322 to join the OED R172 inbound to OED. Passing over OED at or above MEA/MCA one is to proceed on course. Our clearance was JKSN1.OED direct MLBEC which is a course reversal at OED of approximately 180 degrees. Upon joining the radial inbound to OED; the flight director will anticipate the turn extremely early for the next leg and directed a LEFT turn towards terrain out of approximately 4500 feet MSL. A brief moment of confusion occurred as to whether the FMS had been properly programmed before we realized why it was commanding this low turn that did not match up with the SID plate. As we continued TOWARD OED; Departure Control gave us a RIGHT turn to a heading of 110 and 'direct MLBEC when able.' Had this been in dark conditions or before we exited IMC and not been in communication with ATC this may have led us to fly towards terrain and experience EGPWS warnings or worse. The cause of this event is that the FMS is designed to anticipate a turn to the next waypoint and with large direction changes this turn could be well before the waypoint and in this case well too low. Additionally; I believe the SID is coded in our database incorrectly with no altitude limit before allowing a turn away from OED.The SID should be coded with either a flyover waypoint for OED; or a minimum altitude before allowing it to sequence to the next leg. Until that change is made; pilots should be directed to manually alter OED to be a flyover waypoint and not to diverge from that until directed by ATC that we are above any applicable MVA.
ERJ-175 Captain reported ATC issued a turn to avoid terrain after the FMS started an early turn departing MFR.