Narrative:

Descending on final approach for VOR runway 7 to tapa; we received GPWS indications; warning and 'obstacle; obstacle.' we both scanned the 2 miles ahead of us for any obstacle. The pilot flying had leveled off and also confirmed he saw no obstacle. I authorized him to continue the visual approach and landing. We both later inspected the approach plates and charts and could detect no close in obstacle. Upon departing; I tried to find something visually but could only see a couple of radio antennas that might be 200 ft. Is it possible that a new antenna might have been installed along the approach path and commercial chart company not be aware of it? Have any other crews to tapa experienced this warning? Could this be a problem during an IFR approach? Let's look into this before someone finds the obstacle the hard way. Callback conversation with reporter revealed the following information: reporter stated that this was an egpws event and that the obstacle displayed on the captain's pfd since GPWS was not selected for display. Reporter advised that he returned to this airport and the same egpws alert occurred again. Reporter stated that after landing and looking back up the approach course; the crew was able to identify a tower at approximately 1.5 NM from the runway. Reporter estimated the tower was 200 - 250 ft. Reporter advised that his first officer also had the same egpws alert experience at this point on previous flts. On a subsequent callback; the reporter stated that the airport manager notified him of a 592 ft MSL tower at 1.5 NM from the approach end of runway 7 very slightly off centerline. Reporter stated that the airport manager also stated that numerous flight crews have reported the obstacle and at least two go-arounds have followed the warnings. Reporter stated that a foreign carrier servicing the airport did have the obstacle depicted on their proprietary software and charts.

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Original NASA ASRS Text

Title: A B757-200 PLT RPTS A GPWS WARNING ON SHORT FINAL TO TAPA (ST JOHNS; ANTIGUA) WHERE NO OBSTACLE OR ANTENNA IS SHOWN ON CHARTS PRODUCED BY COMMERCIAL COMPANY. TERRAIN MAP ON COCKPIT DISPLAY MOMENTARILY SHOWS OBSTACLE PRESENT.

Narrative: DSNDING ON FINAL APCH FOR VOR RWY 7 TO TAPA; WE RECEIVED GPWS INDICATIONS; WARNING AND 'OBSTACLE; OBSTACLE.' WE BOTH SCANNED THE 2 MILES AHEAD OF US FOR ANY OBSTACLE. THE PLT FLYING HAD LEVELED OFF AND ALSO CONFIRMED HE SAW NO OBSTACLE. I AUTHORIZED HIM TO CONTINUE THE VISUAL APCH AND LNDG. WE BOTH LATER INSPECTED THE APCH PLATES AND CHARTS AND COULD DETECT NO CLOSE IN OBSTACLE. UPON DEPARTING; I TRIED TO FIND SOMETHING VISUALLY BUT COULD ONLY SEE A COUPLE OF RADIO ANTENNAS THAT MIGHT BE 200 FT. IS IT POSSIBLE THAT A NEW ANTENNA MIGHT HAVE BEEN INSTALLED ALONG THE APCH PATH AND COMMERCIAL CHART COMPANY NOT BE AWARE OF IT? HAVE ANY OTHER CREWS TO TAPA EXPERIENCED THIS WARNING? COULD THIS BE A PROB DURING AN IFR APCH? LET'S LOOK INTO THIS BEFORE SOMEONE FINDS THE OBSTACLE THE HARD WAY. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATED THAT THIS WAS AN EGPWS EVENT AND THAT THE OBSTACLE DISPLAYED ON THE CAPT'S PFD SINCE GPWS WAS NOT SELECTED FOR DISPLAY. RPTR ADVISED THAT HE RETURNED TO THIS ARPT AND THE SAME EGPWS ALERT OCCURRED AGAIN. RPTR STATED THAT AFTER LNDG AND LOOKING BACK UP THE APCH COURSE; THE CREW WAS ABLE TO IDENTIFY A TOWER AT APPROX 1.5 NM FROM THE RWY. RPTR ESTIMATED THE TOWER WAS 200 - 250 FT. RPTR ADVISED THAT HIS FO ALSO HAD THE SAME EGPWS ALERT EXPERIENCE AT THIS POINT ON PREVIOUS FLTS. ON A SUBSEQUENT CALLBACK; THE RPTR STATED THAT THE ARPT MANAGER NOTIFIED HIM OF A 592 FT MSL TWR AT 1.5 NM FROM THE APCH END OF RWY 7 VERY SLIGHTLY OFF CENTERLINE. RPTR STATED THAT THE ARPT MANAGER ALSO STATED THAT NUMEROUS FLT CREWS HAVE RPTED THE OBSTACLE AND AT LEAST TWO GO-AROUNDS HAVE FOLLOWED THE WARNINGS. RPTR STATED THAT A FOREIGN CARRIER SERVICING THE ARPT DID HAVE THE OBSTACLE DEPICTED ON THEIR PROPRIETARY SOFTWARE AND CHARTS.

Data retrieved from NASA's ASRS site as of January 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.