Narrative:

I was the sic; and we picked the plane up at the service center. I was pilot flying and occupying the left seat. We were ferrying the plane to pick up a passenger. Pre-flight; engine start; taxi; take-off; climb; and all related checklists were normal. On descent to 17;000 ft; and passing FL190; we heard a muffled bang. There was a shudder followed by continuous vibration. I immediately began to reduce power to slow down. There were no cas messages displayed and engine instruments and pressurization all remained normal. We decided that the captain would call the company and I would fly and communicate with ATC. Center gave us a further descent to 11;000. Maintenance decided we needed to divert. I informed center of the change of destination. They wanted us to climb to 14;000 ft for the new route. Climbing through 12;000 we both noticed a funny odor and the vibration was getting worse. I requested a level off at 12;000 and that was granted. We proceeded to a divert station; declaring an emergency due to vibration from an unknown source. We configured early in case there was an issue with the gear or flaps. We landed without incident and taxied off and clear of the runway and came to a stop close to the emergency vehicles. We had contact with them and they told us we had significant damage to our right engine. We shut down right there and were later towed to the service center. We found much of the underside cowling of the right engine missing.

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Original NASA ASRS Text

Title: CE680 flight crew experiences a loud bang followed by a low vibration and rumbling during descent for landing. All indications in the cockpit are normal but the crew diverts for maintenance at the company's request. Post flight revealed that most of the bottom of the right engine cowling was missing.

Narrative: I was the SIC; and we picked the plane up at the service center. I was pilot flying and occupying the left seat. We were ferrying the plane to pick up a passenger. Pre-flight; engine start; taxi; take-off; climb; and all related checklists were normal. On descent to 17;000 FT; and passing FL190; we heard a muffled bang. There was a shudder followed by continuous vibration. I immediately began to reduce power to slow down. There were no CAS messages displayed and engine instruments and pressurization all remained normal. We decided that the Captain would call the company and I would fly and communicate with ATC. Center gave us a further descent to 11;000. Maintenance decided we needed to divert. I informed Center of the change of destination. They wanted us to climb to 14;000 FT for the new route. Climbing through 12;000 we both noticed a funny odor and the vibration was getting worse. I requested a level off at 12;000 and that was granted. We proceeded to a divert station; declaring an emergency due to vibration from an unknown source. We configured early in case there was an issue with the gear or flaps. We landed without incident and taxied off and clear of the runway and came to a stop close to the emergency vehicles. We had contact with them and they told us we had significant damage to our right engine. We shut down right there and were later towed to the Service Center. We found much of the underside cowling of the right engine missing.

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.