Narrative:

On arrival into oma; I was the pilot flying. ATIS indicated ILS runway 14L in use; runway 14R closed. I briefed the approach as required. Later; approach control said runway 14R was now open and to expect ILS runway 14R. I briefed it. Shortly thereafter; approach control stated that an airport vehicle was disabled in the runway 14R runway area and to expect ILS runway 14L again. We set up again for ILS runway 14L. Later we were given 'maintain 3;000 ft till established; cleared for ILS runway 14L.' after localizer capture; the first officer and pilot monitoring dialed in 2;400 ft for the stepdown altitude. I began the descent to 2;400 ft. As the aircraft was passing 2;500 ft for 2;400 ft and altitude capture was engaging; we received 'caution obstacle.' I disengaged the autopilot; added power; and climbed; but only about 200-300 ft. We saw no obstacle on the display in our immediate flight path; but there was a tower west of the airport; which I included in the approach briefing that stood 2;548 ft. In addition; there are towers along the approach path that can be very difficult to see on the approach page as they blend in with the final approach course symbology. Our last assigned altitude was 3;000 ft; and I should have at the very least returned to that altitude. We eventually captured GS at about 2;700 ft and resumed the approach with no further problems. In the future; I will be more careful of descending to lower stepdown altitudes based on obstacles or terrain. If I can safely fly the approach at the higher vector altitude given by ATC; I will do so -- especially at airports and runways that I don't routinely fly to. Also; I failed to perform the proper procedure as outlined in the fom. As many times as I have studied and 'chair-flown' the go around procedure for 'caution obstacle' at night or IMC; I still only climbed a few hundred ft. Being in the real situation led me into a process of trying to analyze the entire situation of thinking of the long list of ground proximity cautions and which ones require a go around and at what times they are required. If ever in the situation again; I will immediately go around. Before making a stepdown on approach; I will not decide first; is this stepdown necessary to safely and/or procedurally accomplish this approach; or can I just stay at my higher vector altitude and intercept the GS there? I failed to perform a complete go around as outlined in the fom for a 'caution obstacle' at night or IMC. When it happens real-time; it can be easy to try and analyze what's happening when you are on localizer and trying to automatically remember which situation requires a go around per the fom. It's easy to remember on the ground; but can be much more surprising in the air. Maybe one 'caution' or 'too low terrain' while in the simulator during pcs/pts would help serve as a reminder for real world. I also think that it should be done during an approach in the simulator; and not as a training event in the simulator when you know its coming.

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Original NASA ASRS Text

Title: A B737 crew received an EGPWS Obstacle warning at 2500 FT near the OMA Runway 14L BUFFT FAF while descending to 2400 FT. A go-around was initiated but quickly abandoned and the glideslope recaptured for a normal approach.

Narrative: On arrival into OMA; I was the Pilot Flying. ATIS indicated ILS Runway 14L in use; Runway 14R closed. I briefed the approach as required. Later; Approach Control said Runway 14R was now open and to expect ILS Runway 14R. I briefed it. Shortly thereafter; Approach Control stated that an airport vehicle was disabled in the Runway 14R runway area and to expect ILS Runway 14L again. We set up again for ILS Runway 14L. Later we were given 'maintain 3;000 FT till established; cleared for ILS Runway 14L.' After LOC capture; the First Officer and Pilot Monitoring dialed in 2;400 FT for the stepdown altitude. I began the descent to 2;400 FT. As the aircraft was passing 2;500 FT for 2;400 FT and altitude capture was engaging; we received 'Caution Obstacle.' I disengaged the autopilot; added power; and climbed; but only about 200-300 FT. We saw no obstacle on the display in our immediate flight path; but there was a tower west of the airport; which I included in the approach briefing that stood 2;548 FT. In addition; there are towers along the approach path that can be very difficult to see on the approach page as they blend in with the final approach course symbology. Our last assigned altitude was 3;000 FT; and I should have at the very least returned to that altitude. We eventually captured GS at about 2;700 FT and resumed the approach with no further problems. In the future; I will be more careful of descending to lower stepdown altitudes based on obstacles or terrain. If I can safely fly the approach at the higher vector altitude given by ATC; I will do so -- especially at airports and runways that I don't routinely fly to. Also; I failed to perform the proper procedure as outlined in the FOM. As many times as I have studied and 'chair-flown' the go around procedure for 'Caution Obstacle' at night or IMC; I still only climbed a few hundred FT. Being in the real situation led me into a process of trying to analyze the entire situation of thinking of the long list of ground proximity cautions and which ones require a go around and at what times they are required. If ever in the situation again; I will immediately go around. Before making a stepdown on approach; I will not decide first; is this stepdown necessary to safely and/or procedurally accomplish this approach; or can I just stay at my higher vector altitude and intercept the GS there? I failed to perform a complete go around as outlined in the FOM for a 'Caution Obstacle' at night or IMC. When it happens real-time; it can be easy to try and analyze what's happening when you are on LOC and trying to automatically remember which situation requires a go around per the FOM. It's easy to remember on the ground; but can be much more surprising in the air. Maybe one 'caution' or 'too low terrain' while in the simulator during PCs/PTs would help serve as a reminder for real world. I also think that it should be done during an approach in the simulator; and not as a training event in the simulator when you know its coming.

Data retrieved from NASA's ASRS site as of May 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.