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|
Attributes | |
ACN | 870508 |
Time | |
Date | 201001 |
Local Time Of Day | 1201-1800 |
Place | |
Locale Reference | APN.Airport |
State Reference | MI |
Environment | |
Flight Conditions | IMC |
Light | Daylight |
Aircraft 1 | |
Make Model Name | Commercial Fixed Wing |
Flight Phase | Initial Approach |
Flight Plan | IFR |
Component | |
Aircraft Component | GPWS |
Person 1 | |
Function | Captain Pilot Flying |
Experience | Flight Crew Last 90 Days 13 Flight Crew Total 8000 Flight Crew Type 7000 |
Events | |
Anomaly | Inflight Event / Encounter CFTT / CFIT |
Narrative:
Weather in apn was favoring the south runway with strong gusty winds out of the south prohibiting a landing on runway 1 due to excessive tailwind. The ceiling was reported at 600 ft overcast; variable from 400-1000. We shot the VOR runway 19 for that reason. On our first attempt we received a GPWS terrain warning at approximately 7 mile final and approximately 1600 ft. The GPWS instructed us to pull up and so we performed a go-around below 1000 ft AGL. We entered the holding pattern and re-briefed the approach to make sure we were correct in our position and altitude at the time of the terrain call. We also discussed when and where the go-around commenced so that we could be prepared for the possibility of it occurring again. We concluded that we were not at fault and decided to attempt the approach again. On the second attempt the same thing happened at the same altitude and location. The taws in this aircraft is showing a 1700 ft obstacle off to the left of the inbound course for the VOR runway 19 in apn. We again entered the hold. The first thing the dispatcher; wanted to do was transfer me to maintenance control because maybe there was something wrong with the taws. I told him it wasn't mechanical but even if it was; I wasn't shooting another approach down to minimums with a malfunctioning taws anyway. I told him I wanted to abandon our attempts into apn. He said he looked at the winds in apn and it worked out to a 7.8 KT tailwind for the ILS. I stated that I just checked the weather before I called him and it was gusting to 24 KTS which put us decidedly over the 10 KT tailwind limitation. I talked with my crew and felt that if we did attempt another VOR and we had another terrain call and go-around how stressful that would be for a third time in two flights. I felt as though the dispatcher was questioning the plan that was made on the ground prior to departure. I got questioned something like 'so are you sure you don't want to do the VOR?' I again stated that the weather was not cooperating; as now it was a 400 ft ceiling and the approach only allows us to get down to 417 ft AGL and I'm not taking the risk because of yet another terrain go-around with this aircraft. It was decided that we would continue our planned alternate. The flight continued without incident. The approach plate for this approach is from 2004. It may need to be updated with new information if there is terrain or a new obstacle near the approach path. Or maybe there is a possibility of something in the taws database that is incorrect. Either way it should be addressed. I understand that dispatch has a job of getting airplanes to their intended positions but they didn't seem to take a terrain GPWS indication very seriously and seemed to want to keep trying even though it was an obvious issue. I don't think they understand how stressful that can be in actual IFR conditions down to minimums when you are told you are getting near terrain and if you don't execute a go-around it could potentially be a crash. And it's especially stressful when it happens multiple times. I think since these airplanes have had false indications in the past; treat most of these occurrences as such; which is a bad habit.
Original NASA ASRS Text
Title: A TAWS/EGPWS equipped aircraft twice detected an uncharted 1;700' obstacle about 7 NM north of APN while flying the VOR Runway 19 approach IMC. A go around was executed. This may be a charting or database error.
Narrative: Weather in APN was favoring the south runway with strong gusty winds out of the south prohibiting a landing on Runway 1 due to excessive tailwind. The ceiling was reported at 600 FT overcast; variable from 400-1000. We shot the VOR Runway 19 for that reason. On our first attempt we received a GPWS Terrain warning at approximately 7 mile final and approximately 1600 FT. The GPWS instructed us to pull up and so we performed a go-around below 1000 FT AGL. We entered the holding pattern and re-briefed the approach to make sure we were correct in our position and altitude at the time of the terrain call. We also discussed when and where the go-around commenced so that we could be prepared for the possibility of it occurring again. We concluded that we were not at fault and decided to attempt the approach again. On the second attempt the same thing happened at the same altitude and location. The TAWS in this aircraft is showing a 1700 Ft obstacle off to the left of the inbound course for the VOR Runway 19 in APN. We again entered the hold. The first thing the Dispatcher; wanted to do was transfer me to Maintenance Control because maybe there was something wrong with the TAWS. I told him it wasn't mechanical but even if it was; I wasn't shooting another approach down to minimums with a malfunctioning TAWS anyway. I told him I wanted to abandon our attempts into APN. He said he looked at the winds in APN and it worked out to a 7.8 KT tailwind for the ILS. I stated that I just checked the weather before I called him and it was gusting to 24 KTS which put us decidedly over the 10 KT tailwind limitation. I talked with my crew and felt that if we did attempt another VOR and we had another terrain call and go-around how stressful that would be for a third time in two flights. I felt as though the Dispatcher was questioning the plan that was made on the ground prior to departure. I got questioned something like 'So are you SURE you don't want to do the VOR?' I again stated that the weather was not cooperating; as now it was a 400 FT ceiling and the approach only allows us to get down to 417 FT AGL and I'm not taking the risk because of yet another terrain go-around with this aircraft. It was decided that we would continue our planned alternate. The flight continued without incident. The approach plate for this approach is from 2004. It may need to be updated with new information if there is terrain or a new obstacle near the approach path. Or maybe there is a possibility of something in the TAWS database that is incorrect. Either way it should be addressed. I understand that Dispatch has a job of getting airplanes to their intended positions but they didn't seem to take a Terrain GPWS indication very seriously and seemed to want to keep trying even though it was an obvious issue. I don't think they understand how stressful that can be in actual IFR conditions down to minimums when you are told you are getting near terrain and if you don't execute a go-around it could potentially be a crash. And it's especially stressful when it happens multiple times. I think since these airplanes have had false indications in the past; treat most of these occurrences as such; which is a bad habit.
Data retrieved from NASA's ASRS site as of April 2012 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.