GPWS activated on air carrier widebody transport during SID with radar vectors from oak TRACON.

Attributes
ACN	102722
Time
Date	198901
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : sfo
State Reference	CA
Altitude	msl bound lower : 3000 msl bound upper : 3300
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	tracon : oak tower : dfw
Operator	common carrier : air carrier
Make Model Name	Widebody Transport
Navigation In Use	Other Other
Flight Phase	climbout : intermediate altitude cruise other
Route In Use	departure sid : sid enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp pilot : flight engineer pilot : instrument
Experience	flight time last 90 days : 200 flight time total : 6000 flight time type : 1000
ASRS Report	102722
Person 2
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 : 180 flight time total : 16000
ASRS Report	102245
Events
Anomaly	other spatial deviation
Independent Detector	aircraft equipment other aircraft equipment : unspecified
Resolutory Action	flight crew : exited adverse environment
Consequence	faa : reviewed incident with flight crew
Supplementary
Primary Problem	Ambiguous
Air Traffic Incident	other

Narrative:

We were cleared to takeoff sfo runway 01 and to turn to a heading of 350 degrees. Shortly after takeoff and contacting departure. We were told to maintain 3000' because of traffic at 4000'. While at 3000' we were given new heading of 180 degrees. We were on this heading for approximately 3 mins when terrain warning went off on GPWS. Throttles were advanced and immediate climb begun simultaneous with clearance to 7000'. GPWS remained activated until approximately 3300'. It appears that a GPWS will go off if approximately 1000' above sharply rising terrain. On the sfo approach chart, such terrain exists northwest of the airport and is in all probability what we went over. Since this is more than likely a normal GPWS occurrence, a warning should be printed on sfo approach charts stating that if at minimum sector altitude (in this case 3100'), GPWS might activate when passing over this hill. Such a warning is printed on our 'T' pages for nairobi airport. Exact reading follows: 'if radar vectored south of gg NDB at 9100' expect GPWS activation due to 8074' terrain approximately 3 NM south of gg NDB.'

Original NASA ASRS Text

Title: GPWS ACTIVATED ON ACR WDB DURING SID WITH RADAR VECTORS FROM OAK TRACON.

Narrative: WE WERE CLRED TO TKOF SFO RWY 01 AND TO TURN TO A HDG OF 350 DEGS. SHORTLY AFTER TKOF AND CONTACTING DEP. WE WERE TOLD TO MAINTAIN 3000' BECAUSE OF TFC AT 4000'. WHILE AT 3000' WE WERE GIVEN NEW HDG OF 180 DEGS. WE WERE ON THIS HDG FOR APPROX 3 MINS WHEN TERRAIN WARNING WENT OFF ON GPWS. THROTTLES WERE ADVANCED AND IMMEDIATE CLB BEGUN SIMULTANEOUS WITH CLRNC TO 7000'. GPWS REMAINED ACTIVATED UNTIL APPROX 3300'. IT APPEARS THAT A GPWS WILL GO OFF IF APPROX 1000' ABOVE SHARPLY RISING TERRAIN. ON THE SFO APCH CHART, SUCH TERRAIN EXISTS NW OF THE ARPT AND IS IN ALL PROBABILITY WHAT WE WENT OVER. SINCE THIS IS MORE THAN LIKELY A NORMAL GPWS OCCURRENCE, A WARNING SHOULD BE PRINTED ON SFO APCH CHARTS STATING THAT IF AT MINIMUM SECTOR ALT (IN THIS CASE 3100'), GPWS MIGHT ACTIVATE WHEN PASSING OVER THIS HILL. SUCH A WARNING IS PRINTED ON OUR 'T' PAGES FOR NAIROBI ARPT. EXACT READING FOLLOWS: 'IF RADAR VECTORED S OF GG NDB AT 9100' EXPECT GPWS ACTIVATION DUE TO 8074' TERRAIN APPROX 3 NM S OF GG NDB.'

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