Widebody; Low Wing; 3 Turbojet Eng
Flight Crew Air Transport Pilot (ATP)
Aircraft Equipment Problem Less Severe; Inflight Event / Encounter CFTT / CFIT
Air Traffic Control Issued Advisory / Alert; Flight Crew Executed Go Around / Missed Approach
Aircraft
ILS XXL approach unavailable due to notam (INOP). RNAV XXL Approach. Vectored to final approach segment. Marginal weather above minimums. Crew recognized the profile data and the VDI were not consistent inside the final approach fix. Crew initiated go-around and advised tower. Tower advised 'low altitude alert' simultaneously. Crew returned after vectors for the same approach RNAV XXL to an uneventful landing. Crew debriefed the first and second approach. Overall; excellent team effort to identify the situation and go-around.RNAV approaches require 'cleared; established; and protected' guidance to perform properly. ALL of those criteria were met - however - inside the FAF; the crew recognized the data was improper with reference to the VDI. This discrepancy led to the decision to go-around and reset for another approach. The second approach performed with good data and no discrepancies.More proficiency training in the simulator and during normal operations on the line (choosing to practice these approaches more often). As always; if something isn't right or unstable -- Go-Around!
[Report narrative contained no additional information.]
Air carrier flight crew on RNAV approach noticed vertical information was not consistent with the approach. They executed a missed approach simultaneously with Tower advising a low altitude alert.