Narrative:

On jul/mon/07; flight departed ZZZ from runway 19R. After the after takeoff flows were complete we (flight deck crew) observed a right reverser unlocked master caution. We followed our epc and cfm per company policy; declared an emergency; requested vectors to lower our landing weight and returned to ZZZ without further problem or incident. The landing was single engine as directed by our flight manual for that indication.

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Original NASA ASRS Text

Title: A CRJ-200 CAPT REPORTS RECEIVING A R REV UNLOCK MASTER CAUTION SHORTLY AFTER TAKEOFF. THEY DECLARED AN EMERGENCY AND RETURNED TO DEP ARPT.

Narrative: ON JUL/MON/07; FLT DEPARTED ZZZ FROM RWY 19R. AFTER THE AFTER TKOF FLOWS WERE COMPLETE WE (FLT DECK CREW) OBSERVED A R REVERSER UNLOCKED MASTER CAUTION. WE FOLLOWED OUR EPC AND CFM PER COMPANY POLICY; DECLARED AN EMER; REQUESTED VECTORS TO LOWER OUR LNDG WT AND RETURNED TO ZZZ WITHOUT FURTHER PROB OR INCIDENT. THE LNDG WAS SINGLE ENG AS DIRECTED BY OUR FLT MANUAL FOR THAT INDICATION.

Data retrieved from NASA's ASRS site as of January 2009 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.