Narrative:

While enroute at cruise altitude; approximately 40-50 NM south of ZZZ; we experienced smoke/burning odor (almost electrical-like smell) from inside the cockpit. My head was down changing frequencies to the next controller via the FMS when the captain immediately said 'oh s*** did you see that!?' and begun pulling out her smoke goggles and oxygen mask. In hindsight; my initial split reaction was that we lost our number 1 pack (only pack as #2 pack was MEL'ed) and I remember feeling a 'bump' in pressure in my ears and I immediately checked the EICAS for pressurization; which was nominal. Again; initially I did not see the smoke as it appeared on the captain's side first. Only after checking EICAS and then looking over at the captain did I see the smoke; and the horrible burning smell drifted to my side and I donned my oxygen mask/smoke goggles. We immediately ran the iac checklist for cabin fire/smoke and completed the items as per the QRH; and decided to declare an emergency and divert to ZZZ. While running the QRH the flight attendant called us and said the cabin had smoke and a burning smell as well; and she noted that she heard a 'pop' or 'scratching' noise come from somewhere in the middle of the aircraft just before the smoke and burning smell. The captain briefed the flight attendant on our intentions to divert as well as test brief in case of possible evacuation. Notably; we turned the recirculation fan off to try to keep the smoke from circulating; and it appeared to help as the smoke subsided dramatically. Around 10;000 ft we took off our oxygen masks/goggles as it appeared the smoke dissipated from the cockpit...the burning odor still lingered; however. ATC did a fantastic job with handling our emergency situation and we landed in ZZZ without any injuries to passengers/crew. In the descent; I would like to mention the captain and I both had good communication and talked about both possibilities of evacuating on the runway (if smoke got worse) or if we could taxi off to the gate. It was noted that upon landing the captain taxied clear of the runway and we stopped to verify with the flight attendant if the people were okay and smoke had vanished; at the same time we also got a caution 'pack 1 ovht' EICAS message; not sure if it was related to the problem in flight or not; but it was duly noted by the captain and myself. The cabin was clear of smoke and we taxied to the gate and shut the aircraft down per the checklist and deplaned the passengers. The smoke/burning smell in the cabin and cockpit could have been a result of the pop 'noise' the flight attendant recalled hearing in the [middle] of the airplane; which led to us taking immediate but controlled action to divert and land as soon as possible. We did not know if there was a fire somewhere in the aircraft that could get worse and was not indicating to us on the EICAS. I learned a valuable lesson that in an emergency situation: you don't know what you don't know. The source of the problem might not always be obvious; but none the less declare the emergency and stick with it and land the plane in the interest of safety. I believed the captain and I worked well and promptly together to get the plane on the ground safely. There is a big problem I do have; however. Once we told dispatch we were diverting to ZZZ for cockpit smoke; dispatch wrote back that they let ops know we were coming on an emergency. Although once we got to the gate ops said; and I quote; 'hold on don't park at gate X yet we're not ready; who are you by the way; we might need to find a new gate for you'...mind you; all gates were open...we were inbound on emergency-smoke in cockpit and they told us to 'wait'; especially after dispatch claimed they let them know 20-25 minutes out ....also should be noted once we parked; I saw 2 people sitting down in front of the aircraft not offering to help hook up gpu or ask us if we needed anything...it was a very poor show of operation for an aircraft that justdiverted for smoke in the cabin...if I could make a request perhaps there should be immediate protocol standardized for all stations if they hear 'aircraft diverting for emergency' that they be ready to tend to that aircraft whatever the needs are. Also I want to note that while in ZZZ; not once did anyone in the company call either of the crew members to thank us for getting the plane safely on the ground or checking on our well being and if we were okay to continue the rest of our day of flying; even though we sat at the airport for 6 hours and then continued flying 2 more legs and finished about [very late]....about 3 different people (maintenance; flight ops; crew coordinators) however were harassing the captain while sitting in ZZZ to go with contract maintenance back on the airplane and running up the engines to try to 'duplicate' the problem. I thought it was highly unprofessional to try to pressure someone who a) isn't maintenance or an experimental pilot and b) we just declared an emergency for a reason; a bit of gratitude and thanks would be nice versus; 'we need to duplicate the problem so contract maintenance can let us know the problem. Go back on the plane and start troubleshooting now'; who by the way said he would not be able to fix or possibly find whatever issue caused the smoke to begin with to us while sitting in the terminal. The captain refused to do this and I stand behind that decision.

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Original NASA ASRS Text

Title: EMB145 First Officer describes a smoke and fume event while at cruise altitude. QRH procedures are very effective at eliminating the smoke and the flight diverts to the nearest suitable airport.

Narrative: While enroute at cruise altitude; approximately 40-50 NM south of ZZZ; we experienced smoke/burning odor (almost electrical-like smell) from inside the cockpit. My head was down changing frequencies to the next controller via the FMS when the Captain immediately said 'oh s*** did you see that!?' and begun pulling out her smoke goggles and oxygen mask. In hindsight; my initial split reaction was that we lost our number 1 pack (only pack as #2 pack was MEL'ed) and I remember feeling a 'bump' in pressure in my ears and I immediately checked the EICAS for pressurization; which was nominal. Again; initially I did not see the smoke as it appeared on the Captain's side first. Only after checking EICAS and then looking over at the Captain did I see the smoke; and the horrible burning smell drifted to my side and I donned my oxygen mask/smoke goggles. We immediately ran the IAC checklist for Cabin Fire/Smoke and completed the items as per the QRH; and decided to declare an emergency and divert to ZZZ. While running the QRH the Flight Attendant called us and said the cabin had smoke and a burning smell as well; and she noted that she heard a 'pop' or 'scratching' noise come from somewhere in the middle of the aircraft just before the smoke and burning smell. The Captain briefed the Flight Attendant on our intentions to divert as well as TEST brief in case of possible evacuation. Notably; we turned the Recirculation fan off to try to keep the smoke from circulating; and it appeared to help as the smoke subsided dramatically. Around 10;000 FT we took off our oxygen masks/goggles as it appeared the smoke dissipated from the cockpit...the burning odor still lingered; however. ATC did a fantastic job with handling our emergency situation and we landed in ZZZ without any injuries to passengers/crew. In the descent; I would like to mention the Captain and I both had good communication and talked about both possibilities of evacuating on the runway (if smoke got worse) or if we could taxi off to the gate. It was noted that upon landing the Captain taxied clear of the runway and we stopped to verify with the Flight Attendant if the people were okay and smoke had vanished; at the same time we also got a CAUTION 'PACK 1 OVHT' EICAS MSG; not sure if it was related to the problem in flight or not; but it was duly noted by the Captain and myself. The cabin was clear of smoke and we taxied to the gate and shut the aircraft down per the checklist and deplaned the passengers. The smoke/burning smell in the cabin and cockpit could have been a result of the pop 'noise' the Flight Attendant recalled hearing in the [middle] of the airplane; which led to us taking immediate but controlled action to divert and land as soon as possible. We did not know if there was a fire somewhere in the aircraft that could get worse and was not indicating to us on the EICAS. I learned a valuable lesson that in an emergency situation: you don't know what you don't know. The source of the problem might not always be obvious; but none the less declare the emergency and stick with it and land the plane in the interest of safety. I believed the Captain and I worked well and promptly together to get the plane on the ground safely. There is a big problem I do have; however. Once we told Dispatch we were diverting to ZZZ for cockpit smoke; Dispatch wrote back that they let Ops know we were coming on an emergency. Although once we got to the gate Ops said; and I quote; 'Hold on don't park at Gate X yet we're not ready; who are you by the way; we might need to find a new gate for you'...mind you; all gates were open...we were inbound on emergency-smoke in cockpit and they told us to 'wait'; especially after Dispatch claimed they let them know 20-25 minutes out ....also should be noted once we parked; I saw 2 people sitting down in front of the aircraft not offering to help hook up GPU or ask us if we needed anything...it was a very poor show of operation for an aircraft that justdiverted for smoke in the cabin...if I could make a request perhaps there should be immediate protocol standardized for all stations if they hear 'aircraft diverting for emergency' that they be ready to tend to that aircraft whatever the needs are. Also I want to note that while in ZZZ; not once did anyone in the company call either of the crew members to thank us for getting the plane safely on the ground or checking on our well being and if we were okay to continue the rest of our day of flying; even though we sat at the airport for 6 hours and then continued flying 2 more legs and finished about [very late]....about 3 different people (Maintenance; Flight Ops; crew coordinators) however were harassing the Captain while sitting in ZZZ to go with Contract Maintenance back on the airplane and running up the engines to try to 'duplicate' the problem. I thought it was highly unprofessional to try to pressure someone who a) isn't Maintenance or an experimental pilot and b) we just declared an emergency for a reason; a bit of gratitude and thanks would be nice versus; 'We need to duplicate the problem so Contract Maintenance can let us know the problem. Go back on the plane and start troubleshooting now'; who by the way said he would not be able to fix or possibly find whatever issue caused the smoke to begin with to us while sitting in the terminal. The Captain refused to do this and I stand behind that decision.

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.