CRJ200 flight crew descending to 2000 ft south of rdu receives GPWS obstacle warning and initiates i...

Attributes
ACN	770616
Time
Date	200801
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : rdu.airport
State Reference	NC
Altitude	msl single value : 2500
Environment
Flight Conditions	IMC
Weather Elements	Turbulence Windshear
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : rdu.tracon
Operator	common carrier : air carrier
Make Model Name	Regional Jet 200 ER&LR
Operating Under FAR Part	Part 121
Navigation In Use	ils localizer & glide slope : 5r
Flight Phase	descent : approach
Route In Use	approach : instrument precision arrival : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Experience	flight time last 90 days : 20 flight time total : 10000 flight time type : 3000
ASRS Report	770616
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer observation : company check pilot
Experience	flight time last 90 days : 20 flight time total : 20000 flight time type : 12000
ASRS Report	770617
Events
Anomaly	conflict : airborne less severe
Independent Detector	aircraft equipment : gpws
Resolutory Action	aircraft : equipment problem dissipated flight crew : took precautionary avoidance action
Supplementary
Problem Areas	Flight Crew Human Performance ATC Human Performance
Primary Problem	Flight Crew Human Performance

Narrative:

During radar vectors to ILS runway 5R; on downwind we were assigned a descent clearance to 2000 ft. At approximately 2500 ft we received an 'obstacle; obstacle' GPWS warning. Within about 5 seconds; the autoplt was disconnected and a climb was initiated. At the same time the first officer advised the controller that we were deviating to a higher altitude due to the warning. The controller (a different one than before) issued an 'immediate climb' clearance to 3000 ft. Due to the high rate of climb the aircraft went to approximately 3600 ft. We advised ATC that we were returning to 3000 ft. An uneventful ILS approach was completed to a landing on runway 5R.

Original NASA ASRS Text

Title: CRJ200 FLT CREW DESCENDING TO 2000 FT SOUTH OF RDU RECEIVES GPWS OBSTACLE WARNING AND INITIATES IMMEDIATE CLIMB.

Narrative: DURING RADAR VECTORS TO ILS RWY 5R; ON DOWNWIND WE WERE ASSIGNED A DSCNT CLRNC TO 2000 FT. AT APPROX 2500 FT WE RECEIVED AN 'OBSTACLE; OBSTACLE' GPWS WARNING. WITHIN ABOUT 5 SECONDS; THE AUTOPLT WAS DISCONNECTED AND A CLB WAS INITIATED. AT THE SAME TIME THE FO ADVISED THE CTLR THAT WE WERE DEVIATING TO A HIGHER ALT DUE TO THE WARNING. THE CTLR (A DIFFERENT ONE THAN BEFORE) ISSUED AN 'IMMEDIATE CLB' CLRNC TO 3000 FT. DUE TO THE HIGH RATE OF CLB THE ACFT WENT TO APPROX 3600 FT. WE ADVISED ATC THAT WE WERE RETURNING TO 3000 FT. AN UNEVENTFUL ILS APCH WAS COMPLETED TO A LNDG ON RWY 5R.

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

CRJ200 flight crew descending to 2000 ft south of rdu receives GPWS obstacle warning and initiates immediate climb.