The article presents the author's experience during dumping fuel in airborne Rhino (F/-18E/F) flight. While dumping, he saw fuel pouring from vertical stabilizers. The bingo caution illuminated. He mentions that in Rhino, the fuel system is mechanized where we cannot get rid of feed-tank fuel. He wanted the aircraft to cease dumping with about 5,000 pounds of useable fuel remaining. After the action of controller, the de-arm area was cleared and the aircraft started dumping on the flight deck.