Narrative:

While acting as pilot in command on a flight we smelled an electrical burning smell followed by smoke in the cockpit. We were on the RNAV arrival around 12000 ft. We executed an emergency descent to ZZZ airport to land. I was the flying pilot in the left seat while first officer handled the radios and checklist items. During the emergency descent we encountered a TCAS RA and complied with it by climbing and turning to our right towards the north to avoid the VFR aircraft which was not talking to approach. Approach did advise us of the aircraft since it was on radar. After complying with the RA we continued with the emergency descent and checklist items prior to landing. We commenced and complied with the electrical fire or smoke checklist from the ce-560XLS checklist. Once the checklist directed us to place the cabin master and generators to the off position the smoke subsided but the electrical burning smell was still present. I decided to deploy the passenger oxygen masks manually due to the continuing burning electrical smell. We briefed the passengers of the situation and advised them of our plans to immediately land. We landed and cleared runway and performed an evacuation of the aircraft on the taxiway due to the existing electrical burning smell. The landing was normal and uneventful. We immediately disconnected the ship's battery after exiting the aircraft. Fire and airport ops met us at the aircraft. Fire performed a search on the aircraft and advised us that there was no present danger. We had the aircraft [towed] to the ramp. The crew and passengers suffered no injuries or problems from the event.overall I feel as though the first officer and I acted appropriately and worked well together as a crew under the circumstances we were dealing with. There are a lot of things going through your mind when you smell burning and see smoke in an airplane. Our goal was to get the plane on the ground as soon as possible. I would advise all crew members to pay close attention to the TCAS before initiating an emergency descent to avoid any conflicts with other aircraft like we had. I was focused on getting the airplane on the ground and [the first officer] was focused on the checklist and radios. The TCAS system definitely helped to prevent a conflict with the VFR aircraft. Following the appropriate checklist lead to the turning off of several important switches which eventually put an end to the smoke. We both have learned positive things from this event and come out of this as better pilots in my mind.

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Original NASA ASRS Text

Title: A CE-560XLS flight crew reported smoke and fumes on descent so the crew diverted to a nearby airport. Maintenance found a burned set of wires under the forward left galley carpeting and believe that to be the smoke's source. The First Officer commented about the aircraft emergency checklist complexity.

Narrative: While acting as Pilot in Command on a flight we smelled an electrical burning smell followed by smoke in the cockpit. We were on the RNAV arrival around 12000 ft. We executed an emergency descent to ZZZ airport to land. I was the flying pilot in the left seat while First Officer handled the radios and checklist items. During the emergency descent we encountered a TCAS RA and complied with it by climbing and turning to our right towards the north to avoid the VFR aircraft which was not talking to approach. Approach did advise us of the aircraft since it was on radar. After complying with the RA we continued with the emergency descent and checklist items prior to landing. We commenced and complied with the Electrical Fire or Smoke checklist from the CE-560XLS checklist. Once the checklist directed us to place the cabin master and generators to the off position the smoke subsided but the electrical burning smell was still present. I decided to deploy the passenger oxygen masks manually due to the continuing burning electrical smell. We briefed the passengers of the situation and advised them of our plans to immediately land. We landed and cleared runway and performed an evacuation of the aircraft on the taxiway due to the existing electrical burning smell. The landing was normal and uneventful. We immediately disconnected the ship's battery after exiting the aircraft. Fire and airport ops met us at the aircraft. Fire performed a search on the aircraft and advised us that there was no present danger. We had the aircraft [towed] to the ramp. The crew and passengers suffered no injuries or problems from the event.Overall I feel as though the First Officer and I acted appropriately and worked well together as a crew under the circumstances we were dealing with. There are a lot of things going through your mind when you smell burning and see smoke in an airplane. Our goal was to get the plane on the ground as soon as possible. I would advise all crew members to pay close attention to the TCAS before initiating an emergency descent to avoid any conflicts with other aircraft like we had. I was focused on getting the airplane on the ground and [the First Officer] was focused on the checklist and radios. The TCAS system definitely helped to prevent a conflict with the VFR aircraft. Following the appropriate checklist lead to the turning off of several important switches which eventually put an end to the smoke. We both have learned positive things from this event and come out of this as better pilots in my mind.

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.