Narrative:

On takeoff roll above 100 kts; I noticed what I thought was a flock of small white birds on the departure end of the runway. After vr and the 'rotate' call; I realized in the rotation that it was not birds; but a dust devil; tornado type rotation of trash and papers. It was quite large; just left of centerline; but covering most of the runway width; and spanning well above our altitude. The winds seemed to be quite intense; judging by the speed of the trash whirling around. As the airplane began to lift off; I noticed a vibration on the airplane; possibly a buffet; and the airplane did not seem to be climbing as expected. I began to reach for the thrust levers but was forced back to the yoke when we hit the dust devil and the airplane aggressively rolled to the left. The captain and I both applied aggressive roll input in the opposite direction. The aircraft was slow to respond; but eventually did and returned to level flight. I did not have time to look at the instruments and notate the roll angle or airspeed loss; but there were no aural or tactile alerts from the aircraft. Once through the dust devil; the aircraft climbed normally; and the rest of the flight was uneventful.

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Original NASA ASRS Text

Title: B737NG First Officer reported encountering a dust devil shortly after takeoff that resulted in an uncommanded aggressive roll to the left.

Narrative: On takeoff roll above 100 kts; I noticed what I thought was a flock of small white birds on the departure end of the runway. After VR and the 'Rotate' call; I realized in the rotation that it was not birds; but a dust devil; tornado type rotation of trash and papers. It was quite large; just left of centerline; but covering most of the runway width; and spanning well above our altitude. The winds seemed to be quite intense; judging by the speed of the trash whirling around. As the airplane began to lift off; I noticed a vibration on the airplane; possibly a buffet; and the airplane did not seem to be climbing as expected. I began to reach for the thrust levers but was forced back to the yoke when we hit the dust devil and the airplane aggressively rolled to the left. The captain and I both applied aggressive roll input in the opposite direction. The aircraft was slow to respond; but eventually did and returned to level flight. I did not have time to look at the instruments and notate the roll angle or airspeed loss; but there were no aural or tactile alerts from the aircraft. Once through the dust devil; the aircraft climbed normally; and the rest of the flight was uneventful.

Data retrieved from NASA's ASRS site 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.