A B767-300 flight crew; early in a trans-oceanic flight; received a 'WX radar weak' error message. T...

Attributes
ACN	786768
Time
Date	200805
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	msl single value : 31000
Aircraft 1
Controlling Facilities	artcc : zzz.artcc
Operator	common carrier : air carrier
Make Model Name	B767-300 and 300 ER
Operating Under FAR Part	Part 121
Flight Phase	climbout : initial ground : preflight
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
ASRS Report	786768
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
ASRS Report	786563
Events
Anomaly	aircraft equipment problem : less severe
Independent Detector	other flight crewa
Resolutory Action	flight crew : landed as precaution flight crew : declared emergency flight crew : diverted to another airport
Consequence	other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

Radar failure prior oceanic crossing. 10 mins after departing; turned WX radar on and received WX radar weak message. Tested radar and received WX fail message. Contacted maintenance who advised WX radar weak was an impending failure message. Contacted dispatch who coordination our diversion to ZZZ to fix radar/change aircraft and advised them of our overweight status and our need to dump fuel. Notified ATC and began fuel dump over zzzzz intersection and terminated prior to landfall near xyz. Dumped remaining center tank fuel (13000 pounds) in 5 mins at FL350. Consulted performance manual quick turnaround weight brake cool-down chart and then descended to FL210 to burn off additional fuel to avoid 75 min takeoff delay requirement for landing weights above 328000 pounds. Informed purser on our overweight landing status and had cabin crew brief passenger on precautionary emergency landing procedures. Notified ZZZ approach control of our overweight landing status; declared emergency and requested crash fire rescue equipment due to same. After 20 mins of vectoring for fuel burn-off; received permission to land. Xferred control of the aircraft from the first officer to captain and landed flaps 30 degrees with automatic brakes at a touchdown sink rate of 75 FPM. Had crash fire rescue equipment crew chief inspect brakes after uneventful landing and then taxied to gate.

Original NASA ASRS Text

Title: A B767-300 FLT CREW; EARLY IN A TRANS-OCEANIC FLT; RECEIVED A 'WX RADAR WEAK' ERROR MESSAGE. THEY DECLARED AN EMERGENCY AND DIVERTED TO A SUITABLE AIRPORT.

Narrative: RADAR FAILURE PRIOR OCEANIC XING. 10 MINS AFTER DEPARTING; TURNED WX RADAR ON AND RECEIVED WX RADAR WEAK MESSAGE. TESTED RADAR AND RECEIVED WX FAIL MESSAGE. CONTACTED MAINT WHO ADVISED WX RADAR WEAK WAS AN IMPENDING FAILURE MESSAGE. CONTACTED DISPATCH WHO COORD OUR DIVERSION TO ZZZ TO FIX RADAR/CHANGE ACFT AND ADVISED THEM OF OUR OVERWT STATUS AND OUR NEED TO DUMP FUEL. NOTIFIED ATC AND BEGAN FUEL DUMP OVER ZZZZZ INTXN AND TERMINATED PRIOR TO LANDFALL NEAR XYZ. DUMPED REMAINING CTR TANK FUEL (13000 LBS) IN 5 MINS AT FL350. CONSULTED PERFORMANCE MANUAL QUICK TURNAROUND WT BRAKE COOL-DOWN CHART AND THEN DSNDED TO FL210 TO BURN OFF ADDITIONAL FUEL TO AVOID 75 MIN TKOF DELAY REQUIREMENT FOR LNDG WTS ABOVE 328000 LBS. INFORMED PURSER ON OUR OVERWT LNDG STATUS AND HAD CABIN CREW BRIEF PAX ON PRECAUTIONARY EMER LNDG PROCS. NOTIFIED ZZZ APCH CTL OF OUR OVERWT LNDG STATUS; DECLARED EMER AND REQUESTED CFR DUE TO SAME. AFTER 20 MINS OF VECTORING FOR FUEL BURN-OFF; RECEIVED PERMISSION TO LAND. XFERRED CTL OF THE ACFT FROM THE FO TO CAPT AND LANDED FLAPS 30 DEGS WITH AUTO BRAKES AT A TOUCHDOWN SINK RATE OF 75 FPM. HAD CFR CREW CHIEF INSPECT BRAKES AFTER UNEVENTFUL LNDG AND THEN TAXIED TO GATE.

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.

A B767-300 flight crew; early in a trans-oceanic flight; received a 'WX radar weak' error message. They declared an emergency and diverted to a suitable airport.