Medium Transport
Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine; Flight Crew Instrument
Workload; Situational Awareness; Confusion; Fatigue
Deviation - Altitude Overshoot; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter CFTT / CFIT
Airspace Structure; Chart Or Publication; Weather; Software and Automation; Procedure; Human Factors
On the 4th leg of the day and short overnight due to getting in 2 hrs late the night before. Leaving ZZZ1 to ZZZ; the weather was clear and planning for a Visual; but backing it up with an approach per the company night visual policy. We choose the RNAV XX due to wanting something other than the ILS and not having flown the RNAV XX other than in the simulator. Once airborne and talking to Center we got slowed to slowest possible speed due to a MedEvac ahead of us on an approach to ZZZ. The MedEvac canceled IFR and allowed us to get cleared for the RNAV XX. We briefed it up as a visual backed up by the RNAV so I did not brief the notes on the approach. Flying the approach when turning final; I notice the PAPI was showing 4 red and thought that odd. I prepared to disconnect Autopilot and climb to the Visual Glide Path; but wanted to see what the approach was doing. Due to being close to the airport and seeing the ridge prior to the airport; I did not want to look at the notes to see if there was a note about the VGSI not coincident. About 200 feet above minimums the GPWS gave a Terrain Terrain warning. I promptly disconnected the Autopilot and climbed to follow the VGSI. We landed safely and checked the altitude to see if our altimeter was set incorrectly. That checked within 10 feet. During the taxi to the ramp; I noticed the cold weather temp comp was required for temps less than -7 deg. When stated; the Captain said something like that should't be the factor; then he looked at the DATA card which was on his yoke; and noticed that the temp was -13 degrees. Captain commented that the cold temp would probably account for the couple hundred feet low on the approach. Lessons learned brief notes when we probably will be flying an approach that ATC clears us for. Try to incorporate Temp Comp which is currently not allowed with any FMS approach even for visual approaches.
While conducting a night Visual Approach to Runway XX in ZZZ; we received a terrain warning. It was night visual conditions; and we were using the RNAV XX for guidance. The reported temperature on the AWOS was -13; which is below what is authorized by the procedure. We had the runway in sight throughout the procedure; and noticed that we were below glideslope on final. The terrain warning occurred while we were correcting our altitude. Although we were following an instrument procedure for the night visual; the visual conditions probably lead to complacency in the approach briefing; leading to the note being missed for the procedure.
Flight crew reported receiving a Ground Proximity Warning while on final approach due to conducting the approach below the authorized minimum air temperature.