Narrative:

On the morning of [date]; the captain and I were operating a ferry maintenance flight from ZZZ to ZZZ1 with the two of us as the only persons onboard. The reason for the ferry flight was pack 2 was meled and needed to be serviced at ZZZ1. The maintenance write up said there was a bleed leak downstream of the pack and that we would be able to use the #2 engine bleed for anti-ice if needed. Captain called maintenance from the gate during preflight checks to double check that bleed 2 may still be used in the event we needed it for anti-ice as heavy fog prevailed over the airport surface. Maintenance said pack 2 could still be used; just without selecting pack #2. [Captain] and I decided I was going to be PF [pilot flying] and she was going to be pm [pilot monitoring] this leg on our way to ZZZ1. We departed ZZZ with no issue and made it up to a cruising altitude of FL250 while talking with center. Approximately 30 miles north of the [VOR]; we detected a scent of what smelled like gun powder or sulfur and a white smoke was beginning to fill the flight deck. The thickness of the smoke was not enough to hamper with our ability to see nor were we able to pin point an exact location/vent of the source. Upon realization that we had smoke in the flight deck; pm made the verbal announcement of smoke on the flight deck. The two of us performed the memory items associated with flight deck smoke/fumes and referenced the iai [immediate action items] to comply with its guidance. Following the iai; pm pulled out the QRH and began running the applicable procedure for cabin smoke/fire. Upon completion; the pm informed ATC we had smoke on the flight deck and that we would need a lower altitude of 12;000 feet. ATC cleared us down to 14;000 feet and shortly after cleared us down to 12;000 feet without a level off. During our descent; ATC notified us of priority handling for us. Pm and I evaluated the situation following the procedures outlined in the QRH and found that the smoke was no longer entering the flight deck. We noted ZZZ2 was the nearest large airport we could divert to if needed while we discussed our options. We found that the situation was under control and the captain asked me what I thought about the situation and if I was comfortable continuing to our destination. Considerations were made to oxygen use and fuel consumption. Since we were at 12;000 feet; we no longer needed to wear oxygen masks and we had 9;000 lbs of fuel at the gate for our flight. Continuing the rest of the way at our new altitude was not an issue with the higher fuel consumption. Both dispatch and maintenance were informed via ACARS throughout the flight. The suspected source of the smoke was from the air conditioning system when powered by bleed 2. The flight continued to the filed destination without further incident.cause: the threat of this flight was evident in the pack 2 MEL.suggestions: as a new first officer [first officer] flying on the line; the events from today helped cement the need for being decisive during critical situations as well as keeping up with the memory items in the iai.

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Original NASA ASRS Text

Title: EMB-145 First Officer reported light amount of smoke in the cockpit accompanied by 'gun powder or sulfur' odor.

Narrative: On the morning of [Date]; the Captain and I were operating a ferry maintenance flight from ZZZ to ZZZ1 with the two of us as the only persons onboard. The reason for the ferry flight was PACK 2 was MELed and needed to be serviced at ZZZ1. The Maintenance write up said there was a bleed leak downstream of the PACK and that we would be able to use the #2 engine BLEED for anti-ice if needed. Captain called Maintenance from the gate during preflight checks to double check that BLEED 2 may still be used in the event we needed it for anti-ice as heavy fog prevailed over the airport surface. Maintenance said PACK 2 could still be used; just without selecting PACK #2. [Captain] and I decided I was going to be PF [Pilot Flying] and she was going to be PM [Pilot Monitoring] this leg on our way to ZZZ1. We departed ZZZ with no issue and made it up to a cruising altitude of FL250 while talking with Center. Approximately 30 miles north of the [VOR]; we detected a scent of what smelled like gun powder or sulfur and a white smoke was beginning to fill the flight deck. The thickness of the smoke was not enough to hamper with our ability to see nor were we able to pin point an exact location/vent of the source. Upon realization that we had smoke in the flight deck; PM made the verbal announcement of smoke on the flight deck. The two of us performed the memory items associated with flight deck smoke/fumes and referenced the IAI [Immediate Action Items] to comply with its guidance. Following the IAI; PM pulled out the QRH and began running the applicable procedure for Cabin Smoke/Fire. Upon completion; the PM informed ATC we had smoke on the flight deck and that we would need a lower altitude of 12;000 feet. ATC cleared us down to 14;000 feet and shortly after cleared us down to 12;000 feet without a level off. During our descent; ATC notified us of priority handling for us. PM and I evaluated the situation following the procedures outlined in the QRH and found that the smoke was no longer entering the flight deck. We noted ZZZ2 was the nearest large airport we could divert to if needed while we discussed our options. We found that the situation was under control and the Captain asked me what I thought about the situation and if I was comfortable continuing to our destination. Considerations were made to oxygen use and fuel consumption. Since we were at 12;000 feet; we no longer needed to wear oxygen masks and we had 9;000 lbs of fuel at the gate for our flight. Continuing the rest of the way at our new altitude was not an issue with the higher fuel consumption. Both Dispatch and Maintenance were informed via ACARS throughout the flight. The suspected source of the smoke was from the Air Conditioning system when powered by BLEED 2. The flight continued to the filed destination without further incident.Cause: The threat of this flight was evident in the PACK 2 MEL.Suggestions: As a new FO [First Officer] flying on the line; the events from today helped cement the need for being decisive during critical situations as well as keeping up with the memory items in the IAI.

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.