An air carrier captain reported receiving GPWS obstacle warning on VOR runway 18 approach to crp.

Attributes
ACN	1224104
Time
Date	201412
Local Time Of Day	0601-1200
Place
Locale Reference	CRP.Airport
State Reference	TX
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	Initial Approach
Flight Plan	IFR
Person 1
Function	Captain
Experience	Flight Crew Last 90 Days 113
Events
Anomaly	Inflight Event / Encounter CFTT / CFIT

Narrative:

While executing the VOR runway 18 approach into crp; we received a caution obstacle GPWS warning prior to reaching the charted step down fix. A missed approach was performed and we were vectored for an ILS to runway 36 resulting in an uneventful landing. Prior to receiving the caution the crew had crosschecked the inbound VOR course using the FMC/LNAV system and determined that we were well established on course. The descent rate at the time of the 'caution' was approximately 300 fpm.

Original NASA ASRS Text

Title: An Air Carrier Captain reported receiving GPWS obstacle warning on VOR Runway 18 approach to CRP.

Narrative: While executing the VOR RWY 18 Approach into CRP; we received a Caution Obstacle GPWS warning prior to reaching the charted step down fix. A missed approach was performed and we were vectored for an ILS to RWY 36 resulting in an uneventful landing. Prior to receiving the Caution the crew had crosschecked the inbound VOR course using the FMC/LNAV system and determined that we were well established on course. The descent rate at the time of the 'Caution' was approximately 300 fpm.

Data retrieved from NASA's ASRS site 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.