I was at home when my grandmother called me saying "look, an ufo" . when i went out i saw a big object in the sky, a big black "raven-looking" object, flying but without emitting any sound. suddenly that object emitted a flame from the back, big at least as the object itself. it was even faster than a normal military plane, and flew along the sky until it disappeared from my wiew range. how can i say that it wasn't a normal aircraft? because it had structurer i've never seen before in any type of plane, like multiple wings (more than 2), a back propeller that emit a big flame and its speed was too high for a normal plane. if that was an airplane, given the flame it emitted, it would certainly have crashed because it was on fire.