Narrative:

Departed. When selected landing gear up; the right main unlock light and green triangle light remained illuminated after other gear lights extinguished. We notified tower; leveled off; and followed the checklist for gear retraction impossible. Tower confirmed that they could tell that the right main did not retract. After selecting the gear down; as per checklist; we got the 3 green and returned to a normal landing. Emergency was declared as a precaution. No other abnormalities noted.

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Original NASA ASRS Text

Title: Flight crew of ATR72 returned to departure airport when the right main gear failed to retract after takeoff.

Narrative: Departed. When selected landing gear up; the right main unlock light and green triangle light remained illuminated after other gear lights extinguished. We notified Tower; leveled off; and followed the checklist for gear retraction impossible. Tower confirmed that they could tell that the right main did not retract. After selecting the gear down; as per checklist; we got the 3 green and returned to a normal landing. Emergency was declared as a precaution. No other abnormalities noted.

Data retrieved from NASA's ASRS site as of April 2012 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.