Narrative:

Normal takeoff; pilot flying announced abnormal vibration. Vibration grew in severity as speed increased maintained airspeed below maneuvering and started air return procedures. On descent vibrations continued and lead to emergency declaration; normal landing.

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Original NASA ASRS Text

Title: An EMB-145 developed a severe vibration after takeoff so the crew declared an emergency and returned to land.

Narrative: Normal takeoff; pilot flying announced abnormal vibration. Vibration grew in severity as speed increased maintained airspeed below maneuvering and started air return procedures. On descent vibrations continued and lead to emergency declaration; normal landing.

Data retrieved from NASA's ASRS site as of July 2013 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.