During climb a md-83 flight crew and flight attendant noticed an airframe vibration and decided on a...

Narrative:

Accelerating and climbing through about 15;000 ft I felt and heard a deep vibration in the aircraft. I asked my first officer if he noticed anything. He said he did. I looked over all the engine gauges and they all looked normal. I felt the flight controls and they seemed normal except for the vibration. I didn't have any uncommanded movements. As we were looking for signs of the source of the vibration; the lead flight attendant called up and asked if we noticed a vibration. With that many people confirming an abnormal situation and not knowing what it was; I thought it was prudent to return to the field to have it inspected. We informed ATC that we wanted to return and also called the departure operations to let them know. As we were in our turn we lost the right generator. Assuming it was related; but not sure; we declared an emergency so as to get an expedited return back to the runway. We landed uneventfully. Upon discussion with maintenance afterward; they believed that bearings inside the generator went bad and that is what was causing the vibration we felt.

Original NASA ASRS Text

Title: During climb a MD-83 flight crew and flight attendant noticed an airframe vibration and decided on a precautionary return to land but the right generator failed so an emergency was declared followed by a normal landing. Maintenance discovered failed generator bearings.

Narrative: Accelerating and climbing through about 15;000 FT I felt and heard a deep vibration in the aircraft. I asked my First Officer if he noticed anything. He said he did. I looked over all the engine gauges and they all looked normal. I felt the flight controls and they seemed normal except for the vibration. I didn't have any uncommanded movements. As we were looking for signs of the source of the vibration; the Lead Flight Attendant called up and asked if we noticed a vibration. With that many people confirming an abnormal situation and not knowing what it was; I thought it was prudent to return to the field to have it inspected. We informed ATC that we wanted to return and also called the departure Operations to let them know. As we were in our turn we lost the right generator. Assuming it was related; but not sure; we declared an emergency so as to get an expedited return back to the runway. We landed uneventfully. Upon discussion with Maintenance afterward; they believed that bearings inside the generator went bad and that is what was causing the vibration we felt.

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.

Attributes
ACN	1082203
Time
Date	201304
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.ARTCC
State Reference	US
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	MD-83
Operating Under FAR Part	Part 121
Flight Phase	Climb
Flight Plan	IFR
Component
Aircraft Component	Generator Drive
Person 1
Function	Captain Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Aircraft Equipment Problem Less Severe

During climb a md-83 flight crew and flight attendant noticed an airframe vibration and decided on a precautionary return to land but the right generator failed so an emergency was declared followed by a normal landing. Maintenance discovered failed generator bearings.