Air carrier flight crew reported receiving an aircraft obstacle warning during approach. Flight crew corrected altitude; continued approach and landed.
Synopsis
Air carrier flight crew reported receiving an aircraft obstacle warning during approach. Flight crew corrected altitude; continued approach and landed.
Narrative
Coming in on LDA Z RWY 19 as number one in the sequence and had higher than normal speeds assigned (190 basically until FERGI then 160 thereafter). Got behind the aircraft for switching HDG/FREQ/NEEDLES for tracking LDA LOC and overshot final a few degrees. Made corrective actions and stopped teaching to remedy situation and thought we got back on LOC but off centered it appeared when calling 0.2 and attempting to follow vertical profile with altitudes on target. Eventually got caution obstacle warning just prior to WEVPU and looked at altimeter to read just above 1;000 and I took over and corrected the airplane back during the VFR maneuver. No obstacles observed over the north side of the river that would've interfered. Weather higher than 5;500 feet and visibility greater than 8sm. Corrected IAP and then landed appropriately within tolerances after 1;000 feet.Cause: Off center of the LOC which caused altitude deviations based on location in relation to final approach course. Unfamiliarity of the FO (First Officer) with IAP especially while trying to learn it.Suggestions: Ensure the airplane is perfectly centered on the LOC for LDA Z 19 because they sometimes do not perfectly center and avoid teaching and takeover prior to an event. Inform the student that if they've never done the approach before then the CA (Captain) will. I asked if he'd done it before and he said yes twice which is why I let him fly it but after landing and parking he said it wasn't the same that he's done the river visual so I said yes those two are very different. Explain the differences in the IAPs to the FO to ensure it is a CA IAP if the FO never completed at least a couple before.
Second reporter narrative
Did not arm NAV mode in time to intercept localizer; therefore received an obstacle aural.Cause: Not being aligned on localizer caused an obstacle aural because on the altitude on the approach.Suggestions: Arm NAV mode sooner; do not allow the aircraft to overshoot the localizer to prevent any unforeseen circumstances.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.