Narrative:

Shortly after departure; I was notified by the flight attendant that a leakage of fuel was observed by one of the passengers. Upon a brief inspection from the cabin; I determined that we had a significant fuel leak coming from the right wing. The leak appeared to be coming between the right aileron and the outboard portion of the wing. At that point; an emergency was declared due to the fact I had no idea what the cause of the leak was. We turned around and landed uneventfully where we were met by emergency personal. I was the captain on the flight performing PNF (pilot not flying) /pm (pilot monitoring) duties at the time of the emergency.

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Original NASA ASRS Text

Title: Gulfstream IV Captain reported returning to departure airport after a fuel leak was noticed by a passenger.

Narrative: Shortly after departure; I was notified by the flight attendant that a leakage of fuel was observed by one of the passengers. Upon a brief inspection from the cabin; I determined that we had a significant fuel leak coming from the right wing. The leak appeared to be coming between the right aileron and the outboard portion of the wing. At that point; an emergency was declared due to the fact I had no idea what the cause of the leak was. We turned around and landed uneventfully where we were met by emergency personal. I was the captain on the flight performing PNF (Pilot Not Flying) /PM (Pilot Monitoring) duties at the time of the emergency.

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.