B757-200 crew had severe windshear on takeoff at sfo.

Attributes
ACN	622309
Time
Date	200312
Day	Sun
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : sfo.airport
State Reference	CA
Altitude	msl single value : 100
Environment
Flight Conditions	IMC
Weather Elements	Windshear Turbulence
Light	Night
Aircraft 1
Controlling Facilities	tower : sfo.tower
Operator	common carrier : air carrier
Make Model Name	B757 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	climbout : initial climbout : takeoff
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Experience	flight time last 90 days : 52 flight time total : 25000 flight time type : 1150
ASRS Report	622309
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	aircraft equipment problem : less severe inflight encounter : weather inflight encounter : turbulence
Independent Detector	aircraft equipment other aircraft equipment : eicas alert other flight crewa other flight crewb
Resolutory Action	none taken : insufficient time
Supplementary
Problem Areas	Weather Environmental Factor
Primary Problem	Weather

Narrative:

Surface winds strong and gusty. ATIS reporting LLWS advisories. No PIREPS. Inbound crew reported 'rough ride down final.' trim setting 3.7 anu. Normal acceleration to vr. At rotation (149 KIAS), the nose was extremely heavy. A slow, but deliberate rotation was accomplished. Maximum power was used for this departure. At approximately 100 ft, the airspeed increased dramatically (in excess of 258 KTS). Further rotation towards the pitch limit indicator was accomplished. At about 3-5 degrees before the pitch limit indicator, the airspeed began to stabilize. Just after liftoff, we received a predicted windshear EICAS message and status message (logbook entry made in ZZZ). It is my opinion that we encountered windshear on departure. The first officer did not notice any overspd sits during flap retraction. The pitch and turbulence had my full attention, therefore, I cannot comment with certainty as to the above. We did retract on schedule once we were clear of the windshear. It should be noted that the airspeed increase was so rapid that the first officer commented after the event he was checking for erroneous airspeed indications throughout the cockpit. (A point I felt was quick thinking on his part.)

Original NASA ASRS Text

Title: B757-200 CREW HAD SEVERE WINDSHEAR ON TKOF AT SFO.

Narrative: SURFACE WINDS STRONG AND GUSTY. ATIS RPTING LLWS ADVISORIES. NO PIREPS. INBOUND CREW RPTED 'ROUGH RIDE DOWN FINAL.' TRIM SETTING 3.7 ANU. NORMAL ACCELERATION TO VR. AT ROTATION (149 KIAS), THE NOSE WAS EXTREMELY HVY. A SLOW, BUT DELIBERATE ROTATION WAS ACCOMPLISHED. MAX PWR WAS USED FOR THIS DEP. AT APPROX 100 FT, THE AIRSPD INCREASED DRAMATICALLY (IN EXCESS OF 258 KTS). FURTHER ROTATION TOWARDS THE PITCH LIMIT INDICATOR WAS ACCOMPLISHED. AT ABOUT 3-5 DEGS BEFORE THE PITCH LIMIT INDICATOR, THE AIRSPD BEGAN TO STABILIZE. JUST AFTER LIFTOFF, WE RECEIVED A PREDICTED WINDSHEAR EICAS MESSAGE AND STATUS MESSAGE (LOGBOOK ENTRY MADE IN ZZZ). IT IS MY OPINION THAT WE ENCOUNTERED WINDSHEAR ON DEP. THE FO DID NOT NOTICE ANY OVERSPD SITS DURING FLAP RETRACTION. THE PITCH AND TURB HAD MY FULL ATTN, THEREFORE, I CANNOT COMMENT WITH CERTAINTY AS TO THE ABOVE. WE DID RETRACT ON SCHEDULE ONCE WE WERE CLR OF THE WINDSHEAR. IT SHOULD BE NOTED THAT THE AIRSPD INCREASE WAS SO RAPID THAT THE FO COMMENTED AFTER THE EVENT HE WAS CHKING FOR ERRONEOUS AIRSPD INDICATIONS THROUGHOUT THE COCKPIT. (A POINT I FELT WAS QUICK THINKING ON HIS PART.)

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.