Mystery Spotter 
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N559NN
American Eagle (operated by Envoy Air or PSA Airlines, both American Eagle affiliates)
CRJ7
Bombardier (now Mitsubishi/Canadair) CRJ-700
The airframe (N559NN) is in the mainline American Eagle livery, operating a regional flight from a United States hub. The CRJ-900 is reliable for short-haul business and commuter travel.