So reports GPWS altitude excursion in climb out of 8000 ft due to hail and turbulence.

Attributes
ACN	510842
Time
Date	200105
Day	Fri
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : rjaa.airport
State Reference	FO
Altitude	msl bound lower : 8000 msl bound upper : 8400
Environment
Flight Conditions	IMC
Weather Elements	Turbulence Rain
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : rjtg.tracon
Operator	common carrier : air carrier
Make Model Name	B747 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	climbout : intermediate altitude
Route In Use	departure sid : 388
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : second officer
Qualification	pilot : multi engine pilot : instrument pilot : flight engineer pilot : commercial pilot : atp
Experience	flight time last 90 days : 180 flight time total : 8000 flight time type : 2500
ASRS Report	510842
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 60 flight time total : 8000 flight time type : 60
ASRS Report	510981
Events
Anomaly	aircraft equipment problem : critical altitude deviation : excursion from assigned altitude inflight encounter : weather inflight encounter : turbulence inflight encounter other non adherence : clearance
Independent Detector	aircraft equipment : gpws other flight crewa other flight crewb
Resolutory Action	flight crew : returned to assigned altitude
Supplementary
Problem Areas	Weather Aircraft
Primary Problem	Aircraft
Air Traffic Incident	Pilot Deviation

Narrative:

On departure from narita, japan, during leveloff at 8000 ft, aircraft encountered moderate rain, hail, and turbulence (GPWS sounded 'pull up) and aircraft altitude reached 8400 ft. Aircraft was promptly returned to 8000 ft. Supplemental information from acn 510981: aircraft in heavy WX/moderate turbulence. Large up- and down-drafts. Went to 8400 ft. Inadvertent GPWS 'whoop, whoop' due to hail.

Original NASA ASRS Text

Title: SO RPTS GPWS ALT EXCURSION IN CLBOUT OF 8000 FT DUE TO HAIL AND TURB.

Narrative: ON DEP FROM NARITA, JAPAN, DURING LEVELOFF AT 8000 FT, ACFT ENCOUNTERED MODERATE RAIN, HAIL, AND TURB (GPWS SOUNDED 'PULL UP) AND ACFT ALT REACHED 8400 FT. ACFT WAS PROMPTLY RETURNED TO 8000 FT. SUPPLEMENTAL INFO FROM ACN 510981: ACFT IN HVY WX/MODERATE TURB. LARGE UP- AND DOWN-DRAFTS. WENT TO 8400 FT. INADVERTENT GPWS 'WHOOP, WHOOP' DUE TO HAIL.

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.