A ce-680 captain reports an electrical smell in the flight station at about the time the mcdu failed...

Narrative:

About 1.5 hours into the flight; the mcdu on the left side failed. Captain found the circuit breaker and noted it was not tripped. I looked through the emergency/abnormal checklist and found no checklist for our situation. After about 10 minutes; captain noted a faint electrical smell which I confirmed. Captain went to the back of the cabin and confirmed that the smell was only in the cockpit. I started looking for the closest airports. When captain returned to the cockpit; we felt the top and back of both mcdus and noted no excessive heat. We noted that the odor appeared to be increasing. Captain declared an emergency and asked ATC to divert to ZZZ. The owner was aware of the odor; we informed him that we were diverting to ZZZ and he used the satellite phone to call services. I completed the descent; approach; and landing checklists and we were on the ground within about 10 minutes. We asked to have the equipment waiting at the airport and they were. At one point when we began our descent the mcdu flickered on for a moment then went back out. I had the emergency/abnormal checklist open on my lap to the electrical system fire or smoke checklist; but we did not accomplish it. There was no fire or smoke and we felt it was vital to land as soon as possible. I barely had time to complete the normal checklists. We were not suffering any effects from the fumes (no burning eyes or trouble breathing) so we did not don the oxygen masks. Also; I attempted to send a brief afis message to maintenance notifying the company that we were diverting to ZZZ; but I do not think it went through. This aircraft had an MEL for the TCAS system. Also; prior to the mcdu failure; we attempted multiple times to retrieve weather for ege and it never completed the request. With hindsight; I wonder if these were precursors to the avionics failure that we experienced. Callback conversation with reporter revealed the following info: the reporter stated that after maintenance removed the mcdu; it was determined that a short existed within the unit and since the smell did not return; that short was the source of the electrical smell.

Original NASA ASRS Text

Title: A CE-680 Captain reports an electrical smell in the flight station at about the time the MCDU failed. The crew declared an emergency and diverted to a nearby airport. No smoke or flames developed.

Narrative: About 1.5 hours into the flight; the MCDU on the left side failed. Captain found the CB and noted it was not tripped. I looked through the Emergency/Abnormal checklist and found no checklist for our situation. After about 10 minutes; Captain noted a faint electrical smell which I confirmed. Captain went to the back of the cabin and confirmed that the smell was only in the cockpit. I started looking for the closest airports. When Captain returned to the cockpit; we felt the top and back of both MCDUs and noted no excessive heat. We noted that the odor appeared to be increasing. Captain declared an emergency and asked ATC to divert to ZZZ. The Owner was aware of the odor; we informed him that we were diverting to ZZZ and he used the satellite phone to call services. I completed the descent; approach; and landing checklists and we were on the ground within about 10 minutes. We asked to have the equipment waiting at the airport and they were. At one point when we began our descent the MCDU flickered on for a moment then went back out. I had the Emergency/Abnormal checklist open on my lap to the Electrical System Fire or Smoke checklist; but we did not accomplish it. There was no fire or smoke and we felt it was vital to land as soon as possible. I barely had time to complete the normal checklists. We were not suffering any effects from the fumes (no burning eyes or trouble breathing) so we did not don the oxygen masks. Also; I attempted to send a brief AFIS message to maintenance notifying the company that we were diverting to ZZZ; but I do not think it went through. This aircraft had an MEL for the TCAS system. Also; prior to the MCDU failure; we attempted multiple times to retrieve weather for EGE and it never completed the request. With hindsight; I wonder if these were precursors to the avionics failure that we experienced. Callback conversation with Reporter revealed the following info: The Reporter stated that after maintenance removed the MCDU; it was determined that a short existed within the unit and since the smell did not return; that short was the source of the electrical smell.

Data retrieved from NASA's ASRS site as of April 2012 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	827188
Time
Date	200903
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.ARTCC
State Reference	US
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Make Model Name	Cessna Citation Sovereign (C680)
Operating Under FAR Part	Part 91
Flight Phase	Cruise
Component
Aircraft Component	FMS/FMC
Person 1
Function	Pilot Flying Captain
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Aircraft Equipment Problem Less Severe Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor

A ce-680 captain reports an electrical smell in the flight station at about the time the mcdu failed. The crew declared an emergency and diverted to a nearby airport. No smoke or flames developed.