Captain of an medium large transport climbed in response to a GPWS warning during a visual approach.

Attributes
ACN	459418
Time
Date	200001
Day	Wed
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : las.airport
State Reference	NV
Altitude	msl single value : 4500
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	tracon : l30.tracon
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Operating Under FAR Part	Part 121
Navigation In Use	other
Flight Phase	descent : approach
Route In Use	approach : straight in approach : visual arrival other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 180 flight time total : 10000 flight time type : 8000
ASRS Report	459418
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument pilot : multi engine
Events
Anomaly	altitude deviation : overshoot other anomaly other other spatial deviation
Independent Detector	aircraft equipment : gpws other flight crewa other flight crewb
Resolutory Action	flight crew : took precautionary avoidance action
Consequence	Other
Supplementary
Problem Areas	Flight Crew Human Performance Airspace Structure
Primary Problem	Flight Crew Human Performance

Narrative:

We were on approach into las. Coming through about 8000 ft, we called runway 1L in sight. We were cleared to a visual approach but were asked by ATC to hold 230 KTS (fast for this point on the approach). To compensate for the extra speed, I flew the approach slightly low. At about 4500 ft we got a 'terrain, pull up' GPWS warning. Although we had clear line of sight to the runway, we initiated an immediate climb. By the time we were done with the response (the warning silencing) we were well above glide path. A normal landing followed. It should be noted that we had an ATC (tower controller) in the jump seat. Both he and the first officer wondered if it may have been an erroneous warning, because we appeared to be clear of all terrain. If it was indeed an accurate warning, I'm glad we had the GPWS on board.

Original NASA ASRS Text

Title: CAPT OF AN MLG CLBED IN RESPONSE TO A GPWS WARNING DURING A VISUAL APCH.

Narrative: WE WERE ON APCH INTO LAS. COMING THROUGH ABOUT 8000 FT, WE CALLED RWY 1L IN SIGHT. WE WERE CLRED TO A VISUAL APCH BUT WERE ASKED BY ATC TO HOLD 230 KTS (FAST FOR THIS POINT ON THE APCH). TO COMPENSATE FOR THE EXTRA SPD, I FLEW THE APCH SLIGHTLY LOW. AT ABOUT 4500 FT WE GOT A 'TERRAIN, PULL UP' GPWS WARNING. ALTHOUGH WE HAD CLR LINE OF SIGHT TO THE RWY, WE INITIATED AN IMMEDIATE CLB. BY THE TIME WE WERE DONE WITH THE RESPONSE (THE WARNING SILENCING) WE WERE WELL ABOVE GLIDE PATH. A NORMAL LNDG FOLLOWED. IT SHOULD BE NOTED THAT WE HAD AN ATC (TWR CTLR) IN THE JUMP SEAT. BOTH HE AND THE FO WONDERED IF IT MAY HAVE BEEN AN ERRONEOUS WARNING, BECAUSE WE APPEARED TO BE CLR OF ALL TERRAIN. IF IT WAS INDEED AN ACCURATE WARNING, I'M GLAD WE HAD THE GPWS ON BOARD.

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.