Air carrier left of centerline on takeoff roll hits dip in runway.

Attributes
ACN	196065
Time
Date	199112
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : sea
State Reference	WA
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other Other
Flight Phase	climbout : takeoff
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : flight engineer pilot : commercial pilot : instrument
Experience	flight time last 90 days : 100 flight time total : 12000 flight time type : 100
ASRS Report	196065
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Events
Anomaly	other anomaly other other spatial deviation
Independent Detector	other flight crewa other other : unspecified
Resolutory Action	flight crew : regained aircraft control
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

I noticed about 100 KTS that we were left of centerline and the copilot and I both mentioned it simultaneously. By that time we were at vr and just prior to liftoff we hit a dip in the runway and then lifted off. I attributed the dip to being left of centerline since I had taken off on 16L many times before and had not noticed such a dip. All cockpit indications were normal. At the gate in sfo a deadheading pilot asked about the takeoff since he was also unaccustomed to the dip on that runway. I then went out and completely checked the exterior and everything was normal. To avoid this in the future I will pay extra close attention to my alignment when taking position since I must have aligned initially left of centerline.

Original NASA ASRS Text

Title: ACR L OF CENTERLINE ON TKOF ROLL HITS DIP IN RWY.

Narrative: I NOTICED ABOUT 100 KTS THAT WE WERE LEFT OF CENTERLINE AND THE COPLT AND I BOTH MENTIONED IT SIMULTANEOUSLY. BY THAT TIME WE WERE AT VR AND JUST PRIOR TO LIFTOFF WE HIT A DIP IN THE RWY AND THEN LIFTED OFF. I ATTRIBUTED THE DIP TO BEING L OF CENTERLINE SINCE I HAD TAKEN OFF ON 16L MANY TIMES BEFORE AND HAD NOT NOTICED SUCH A DIP. ALL COCKPIT INDICATIONS WERE NORMAL. AT THE GATE IN SFO A DEADHEADING PLT ASKED ABOUT THE TKOF SINCE HE WAS ALSO UNACCUSTOMED TO THE DIP ON THAT RWY. I THEN WENT OUT AND COMPLETELY CHKED THE EXTERIOR AND EVERYTHING WAS NORMAL. TO AVOID THIS IN THE FUTURE I WILL PAY EXTRA CLOSE ATTN TO MY ALIGNMENT WHEN TAKING POS SINCE I MUST HAVE ALIGNED INITIALLY L OF CENTERLINE.

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.