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An MD88 air carrier flight crew gets a GPWS terrain warning after starting a steep descent from 3000 ft to 2000 ft while inbound to the initial approach fix. They start their go around response and exceed the go around altitude before being cleared higher. Next approach normal.
| Attributes | |
| ACN | 361927 |
| Time | |
| Date | 199702 |
| Day | Fri |
| Local Time Of Day | 0601 To 1200 |
| Place | |
| Locale Reference | atc facility : iroe airport : bhm |
| State Reference | AL |
| Altitude | msl bound lower : 2500 msl bound upper : 4000 |
| Environment | |
| Flight Conditions | IMC |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | tracon : bhm |
| Operator | common carrier : air carrier |
| Make Model Name | MD-88 |
| Operating Under FAR Part | Part 121 |
| Navigation In Use | Other Other |
| Flight Phase | descent : approach landing : go around |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| Experience | flight time last 90 days : 60 flight time total : 12360 flight time type : 1700 |
| ASRS Report | 361927 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : instrument pilot : commercial |
| Events | |
| Anomaly | altitude deviation : overshoot inflight encounter : weather non adherence : far non adherence : published procedure other spatial deviation |
| Independent Detector | aircraft equipment other aircraft equipment : unspecified other flight crewa |
| Resolutory Action | controller : issued new clearance other |
| Consequence | Other |
| Supplementary | |
| Primary Problem | Flight Crew Human Performance |
| Air Traffic Incident | Pilot Deviation other |
Narrative:
We were cleared for the localizer runway 23 approach to bhm at 3000 ft. When the localizer was captured and within 10 mi of the IAF, I started a descent to 2000 ft, airspeed was 180 KTS, flaps 15 degrees. At 2500 ft the GPWS terrain warning activated. Since we were IFR with a thunderstorm over the field, I executed the terrain avoidance maneuver adding power and pulling the nose up 20 degrees. Unsure why the GPWS activated, I elected to climb to 4000 ft instead of the missed approach altitude of 3000 ft. The copilot requested 4000 ft and we were given 4000 ft by the controller. Due to the aggressiveness of the maneuver, we exceeded 3300 ft before the clearance to 4000 ft was given. Subsequent approach and landing were uneventful. I suspect a high descent rate coupled with rising terrain, and turbulence resulted in the GPWS warning.
Original NASA ASRS Text
Title: AN MD88 ACR FLC GETS A GPWS TERRAIN WARNING AFTER STARTING A STEEP DSCNT FROM 3000 FT TO 2000 FT WHILE INBOUND TO THE INITIAL APCH FIX. THEY START THEIR GAR RESPONSE AND EXCEED THE GAR ALT BEFORE BEING CLRED HIGHER. NEXT APCH NORMAL.
Narrative: WE WERE CLRED FOR THE LOC RWY 23 APCH TO BHM AT 3000 FT. WHEN THE LOC WAS CAPTURED AND WITHIN 10 MI OF THE IAF, I STARTED A DSCNT TO 2000 FT, AIRSPD WAS 180 KTS, FLAPS 15 DEGS. AT 2500 FT THE GPWS TERRAIN WARNING ACTIVATED. SINCE WE WERE IFR WITH A TSTM OVER THE FIELD, I EXECUTED THE TERRAIN AVOIDANCE MANEUVER ADDING PWR AND PULLING THE NOSE UP 20 DEGS. UNSURE WHY THE GPWS ACTIVATED, I ELECTED TO CLB TO 4000 FT INSTEAD OF THE MISSED APCH ALT OF 3000 FT. THE COPLT REQUESTED 4000 FT AND WE WERE GIVEN 4000 FT BY THE CTLR. DUE TO THE AGGRESSIVENESS OF THE MANEUVER, WE EXCEEDED 3300 FT BEFORE THE CLRNC TO 4000 FT WAS GIVEN. SUBSEQUENT APCH AND LNDG WERE UNEVENTFUL. I SUSPECT A HIGH DSCNT RATE COUPLED WITH RISING TERRAIN, AND TURB RESULTED IN THE GPWS WARNING.
Data retrieved from NASA's ASRS site as of July 2007 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.