Narrative:

We were on leg 3 of 3 for the day. The first two legs we noticed a strong smell like something burning. It would come and go; so it was hard to determine where the odor was coming from. On the third leg the smell got considerably stronger. The PNF [pilot not flying] went to check the cabin and return to the cockpit. Upon return; the PNF commented that the smell was concentrated in the cockpit and no smell was apparent in the cabin or galley. Also; on troubleshooting; the PF [pilot flying] noticed that the smell was not coming out of the gaspers. ATC gave us a clearance to descent for our arrival into our destination. Shortly after; grey/white smoke/fumes started illuminating from the lower center panel windscreen. We [notified] ATC and asked for a diversion to ZZZ. The crew donned masks. The PNF coordinated with ATC lower altitude and a direct flight path to the final approach fix for runway xxr at ZZZ. The smoke continued for about 2 minutes then ceased. We removed our masks and returned to headsets thinking the smoke was stopped. About 2 minutes later; the smoke returned; requiring us to return to the mask operation. The smoke continued for about another 2 minutes before stopping. The rest of the flight until landing was operated on headsets. A stable approach was conducted with the priority handling from ATC. A normal landing was performed; taxied off the active runway. Emergency services were standing by to assist if needed. They followed us to the ramp to check on the passengers; crew; and aircraft. No further assistance was required. The flight attendant [flight attendant] took initiative and took care of the passengers watching the cues from the cockpit. After the first occurrence of smoke; the crew notified the flight attendant 10 minutes to landing. On the second occurrence of smoke in the cockpit; the flight attendant directed the passengers to don smoke hoods.

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Original NASA ASRS Text

Title: First Officer reported strong burning fumes during cruise which turned to smoke. Flight crew executed a divert and completed an uneventful landing.

Narrative: We were on leg 3 of 3 for the day. The first two legs we noticed a strong smell like something burning. It would come and go; so it was hard to determine where the odor was coming from. On the third leg the smell got considerably stronger. The PNF [Pilot not Flying] went to check the cabin and return to the cockpit. Upon return; the PNF commented that the smell was concentrated in the cockpit and no smell was apparent in the cabin or galley. Also; on troubleshooting; the PF [Pilot Flying] noticed that the smell was not coming out of the gaspers. ATC gave us a clearance to descent for our arrival into our destination. Shortly after; grey/white smoke/fumes started illuminating from the lower center panel windscreen. We [notified] ATC and asked for a diversion to ZZZ. The crew donned masks. The PNF coordinated with ATC lower altitude and a direct flight path to the final approach fix for RWY XXR at ZZZ. The smoke continued for about 2 minutes then ceased. We removed our masks and returned to headsets thinking the smoke was stopped. About 2 minutes later; the smoke returned; requiring us to return to the mask operation. The smoke continued for about another 2 minutes before stopping. The rest of the flight until landing was operated on headsets. A stable approach was conducted with the priority handling from ATC. A normal landing was performed; taxied off the active runway. Emergency services were standing by to assist if needed. They followed us to the ramp to check on the passengers; crew; and aircraft. No further assistance was required. The FA [Flight Attendant] took initiative and took care of the passengers watching the cues from the cockpit. After the first occurrence of smoke; the crew notified the FA 10 minutes to landing. On the second occurrence of smoke in the cockpit; the FA directed the passengers to don smoke hoods.

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.