EMB ERJ 170/175 ER/LR
Flight Crew Air Transport Pilot (ATP)
Troubleshooting; Confusion; Distraction; Human-Machine Interface
Aircraft Equipment Problem Less Severe; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Provided Assistance; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Returned To Clearance
Aircraft
Prior to push I called Clearance Delivery to check and see if we needed an amendment to the clearance due to recent software issues with the FMS. They said no this departure is fine. As we started our initial climb the intercept fix and first GPS fix moved to different locations on the MFD causing the flight director to show a right turn instead of left. I flew for another few seconds and asked the Captain to get us a heading. When he decided to do so ATC assigned a left turn. Recent issues with the 27.1 Honeywell software. Have SFO Clearance delivery issue headings until it's fixed.
On departure out of SFO we deviated from the published course on the Offshore 1 departure. The offshore requires a turn to intercept the 350 degree radial off of SFO. We continued to fly straight for approximately 4 miles. The flight director on the PFD never commanded a turn; on the map screen of the MFD the point where the turn was supposed to occur continuously 'bumped' to some distance down the road. The First Officer and I both discussed what was happening; as it was happening and knew that a turn was required by the time we decided to ignore the flight directors commands the ATC controller gave us a left turn direct SEGUL. I believe the cause of this event was a glitch in the FMS. A contributing factor is the fact that we as the flight crew did not recognize the problem in a timely enough fashion and make the turn to the appropriate course. In order to avoid an event like this from happening in the future I think that it is important for flight crews to know the departure that is being performed thoroughly and be able to revert to a different from of navigation; either going to VOR nav or advising the ATC of a malfunction FMS and asking for assistance.
EMB-175 flight crew reported an anomaly with the Honeywell FMS version 27.1 software during their initial climb. A navigational error resulted requiring a radar vector from ATC.