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|
Attributes | |
ACN | 274844 |
Time | |
Date | 199406 |
Day | Mon |
Local Time Of Day | 1201 To 1800 |
Place | |
Locale Reference | atc facility : den |
State Reference | CO |
Altitude | msl bound lower : 9000 msl bound upper : 10000 |
Environment | |
Flight Conditions | IMC |
Light | Daylight |
Aircraft 1 | |
Controlling Facilities | tracon : den |
Operator | common carrier : air carrier |
Make Model Name | B737-300 |
Operating Under FAR Part | Part 121 |
Navigation In Use | Other Other |
Flight Phase | descent : approach |
Route In Use | enroute : on vectors |
Flight Plan | IFR |
Person 1 | |
Affiliation | company : air carrier |
Function | flight crew : first officer |
Qualification | pilot : atp |
Experience | flight time last 90 days : 185 flight time total : 8800 flight time type : 2100 |
ASRS Report | 274844 |
Person 2 | |
Affiliation | company : air carrier |
Function | flight crew : captain oversight : pic |
Qualification | pilot : atp |
Experience | flight time last 90 days : 140 flight time total : 10900 flight time type : 2800 |
ASRS Report | 274830 |
Events | |
Anomaly | altitude deviation : excursion from assigned altitude non adherence : clearance other anomaly other |
Independent Detector | aircraft equipment other aircraft equipment : unspecified other controllera other flight crewa |
Resolutory Action | flight crew : took evasive action flight crew : returned to intended course or assigned course |
Consequence | Other |
Supplementary | |
Primary Problem | Aircraft |
Air Traffic Incident | other |
Narrative:
On the approach to runway 35R at den we were being vectored south of the field and west of the final approach course. Some distance just south of engle at 9000 ft MSL and in heavy rainstorms with lightning and light chop we were turned to a base leg. Shortly after turning we received a GPWS warning 'terrain, terrain.' I disconnected the autoplt and began a climb continuing the turn to try to get us out of the WX. During this maneuver the GPWS continued to go off almost continuously with 'terrain, terrain' or 'pull up,' or 'too low, terrain.' also, the turn diverged us significantly from the final approach course. Confign was 170 KTS with flaps at 1 degree. Climb therefore was somewhat slow. Approach control queried us on 'where we were going' and PNF explained our terrain warning. The warnings finally ceased as we leveled at 10000 ft and returned to the final approach course for uneventful landing. Any and all deviations from ATC clrncs were due entirely to continuous terrain warnings in IMC. Area WX was numerous thunderstorms surrounding the field. Contributing factor was my misplaced or inappropriate attempt to be 'smooth' in the recovery actions for passenger comfort rather than an abrupt maneuver to stop the warnings. Also, continuous and loud GPWS warnings were adding to much confusion in the cockpit. Supplemental information from acn 274830: negative factors that effected the situation were the thunderstorms in the area and the rain showers that we were flying in at the time. Positive factors: very familiar with den so that I had thought about the possibility of a warning and that we might have to respond to a warning, I believe let the first officer do a better job by not being totally surprised when it did occur.
Original NASA ASRS Text
Title: GPWS ALARM ACTIVATED AS ACFT IS VECTORED FOR APCH INTO DEN.
Narrative: ON THE APCH TO RWY 35R AT DEN WE WERE BEING VECTORED S OF THE FIELD AND W OF THE FINAL APCH COURSE. SOME DISTANCE JUST S OF ENGLE AT 9000 FT MSL AND IN HVY RAINSTORMS WITH LIGHTNING AND LIGHT CHOP WE WERE TURNED TO A BASE LEG. SHORTLY AFTER TURNING WE RECEIVED A GPWS WARNING 'TERRAIN, TERRAIN.' I DISCONNECTED THE AUTOPLT AND BEGAN A CLB CONTINUING THE TURN TO TRY TO GET US OUT OF THE WX. DURING THIS MANEUVER THE GPWS CONTINUED TO GO OFF ALMOST CONTINUOUSLY WITH 'TERRAIN, TERRAIN' OR 'PULL UP,' OR 'TOO LOW, TERRAIN.' ALSO, THE TURN DIVERGED US SIGNIFICANTLY FROM THE FINAL APCH COURSE. CONFIGN WAS 170 KTS WITH FLAPS AT 1 DEG. CLB THEREFORE WAS SOMEWHAT SLOW. APCH CTL QUERIED US ON 'WHERE WE WERE GOING' AND PNF EXPLAINED OUR TERRAIN WARNING. THE WARNINGS FINALLY CEASED AS WE LEVELED AT 10000 FT AND RETURNED TO THE FINAL APCH COURSE FOR UNEVENTFUL LNDG. ANY AND ALL DEVS FROM ATC CLRNCS WERE DUE ENTIRELY TO CONTINUOUS TERRAIN WARNINGS IN IMC. AREA WX WAS NUMEROUS TSTMS SURROUNDING THE FIELD. CONTRIBUTING FACTOR WAS MY MISPLACED OR INAPPROPRIATE ATTEMPT TO BE 'SMOOTH' IN THE RECOVERY ACTIONS FOR PAX COMFORT RATHER THAN AN ABRUPT MANEUVER TO STOP THE WARNINGS. ALSO, CONTINUOUS AND LOUD GPWS WARNINGS WERE ADDING TO MUCH CONFUSION IN THE COCKPIT. SUPPLEMENTAL INFO FROM ACN 274830: NEGATIVE FACTORS THAT EFFECTED THE SIT WERE THE TSTMS IN THE AREA AND THE RAIN SHOWERS THAT WE WERE FLYING IN AT THE TIME. POSITIVE FACTORS: VERY FAMILIAR WITH DEN SO THAT I HAD THOUGHT ABOUT THE POSSIBILITY OF A WARNING AND THAT WE MIGHT HAVE TO RESPOND TO A WARNING, I BELIEVE LET THE FO DO A BETTER JOB BY NOT BEING TOTALLY SURPRISED WHEN IT DID OCCUR.
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.