Narrative:

We were inbound to lga; level at 18;000 ft in smooth air; no clouds at 300 knots indicated with the autopilot on. No traffic was observed visually; on TCAS or on frequency. Suddenly we hit what I'm convinced was wake turbulence. We snap-rolled violently and in a second or two were out of the wake turbulence. Thankfully we had the seat belt sign on; and the flight attendant was ok; I'm not sure how they didn't get hurt. If a passenger had been up and or an overhead bin open; I think someone would have been hurt. I've been flying here for going on six years; and I've only experienced this once before. That incident was almost identical to this one except we were at about 11;000 ft and nearly the same geographic location. From now on flying into nyc I think I'm going to have the seatbelt sign on and flight attendant seated when we are 30 minutes out.

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Original NASA ASRS Text

Title: CRJ-200 Captain reported the aircraft 'snap-rolled violently' when they encountered wake turbulence inbound to LGA.

Narrative: We were inbound to LGA; level at 18;000 ft in smooth air; no clouds at 300 knots indicated with the autopilot on. No traffic was observed visually; on TCAS or on frequency. Suddenly we hit what I'm convinced was wake turbulence. We snap-rolled violently and in a second or two were out of the wake turbulence. Thankfully we had the seat belt sign on; and the flight attendant was ok; I'm not sure how they didn't get hurt. If a passenger had been up and or an overhead bin open; I think someone would have been hurt. I've been flying here for going on six years; and I've only experienced this once before. That incident was almost identical to this one except we were at about 11;000 ft and nearly the same geographic location. From now on flying into NYC I think I'm going to have the seatbelt sign on and flight attendant seated when we are 30 minutes out.

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.