False GPWS alert causes go around of widebody transport aircraft on approach. Altitude deviation altitude overshot on climb to newly assigned altitude.

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Attributes
ACN	249321
Time
Date	199308
Day	Tue
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : osa
State Reference	FO
Altitude	msl bound lower : 3300 msl bound upper : 7500
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Widebody, Low Wing, 4 Turbojet Eng
Navigation In Use	Other
Flight Phase	descent : approach
Route In Use	enroute airway : osa
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : flight engineer pilot : commercial pilot : atp pilot : instrument
Experience	flight time last 90 days : 40 flight time total : 15000 flight time type : 40
ASRS Report	249321
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp pilot : commercial pilot : instrument
Events
Anomaly	aircraft equipment problem : critical altitude deviation : overshoot other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	controller : issued new clearance flight crew : returned to intended course or assigned course other
Consequence	Other Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

On approach to runway 32L at osaka, received a ground proximity warning at 3300 ft. Captain GS intermittent and first officer GS showing on GS. Captain radar altimeter descending rapidly. Executed missed approach. Ground proximity ceased at about 5500 ft and a level off was initiated. Ground proximity went off again. Commenced another climb. Ground proximity ceased at about 6500 ft. Approach control assigned us 7000 ft. Overshot 7000 ft by about 500 ft. Descended back to 7000 ft. Ground proximity went off again but flag was noted in captain radar altitude intermittently. First officer's radar altimeter was pegged above 2500 ft. Pulled captain radar altimeter circuit breaker and executed another approach with no problems. Barometric altimeters were double-checked for correct setting and found to be correct. Captain's radar altimeter had malfunctioned causing false ground proximity warnings.

Original NASA ASRS Text

Title: FALSE GPWS ALERT CAUSES GAR OF WDB ACFT ON APCH. ALTDEV ALT OVERSHOT ON CLB TO NEWLY ASSIGNED ALT.

Narrative: ON APCH TO RWY 32L AT OSAKA, RECEIVED A GND PROX WARNING AT 3300 FT. CAPT GS INTERMITTENT AND FO GS SHOWING ON GS. CAPT RADAR ALTIMETER DSNDING RAPIDLY. EXECUTED MISSED APCH. GND PROX CEASED AT ABOUT 5500 FT AND A LEVEL OFF WAS INITIATED. GND PROX WENT OFF AGAIN. COMMENCED ANOTHER CLB. GND PROX CEASED AT ABOUT 6500 FT. APCH CTL ASSIGNED US 7000 FT. OVERSHOT 7000 FT BY ABOUT 500 FT. DSNDED BACK TO 7000 FT. GND PROX WENT OFF AGAIN BUT FLAG WAS NOTED IN CAPT RADAR ALT INTERMITTENTLY. FO'S RADAR ALTIMETER WAS PEGGED ABOVE 2500 FT. PULLED CAPT RADAR ALTIMETER CIRCUIT BREAKER AND EXECUTED ANOTHER APCH WITH NO PROBS. BAROMETRIC ALTIMETERS WERE DOUBLE-CHKED FOR CORRECT SETTING AND FOUND TO BE CORRECT. CAPT'S RADAR ALTIMETER HAD MALFUNCTIONED CAUSING FALSE GND PROX WARNINGS.

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.