Whatever it was, if that object was real and it came out from the water, it didn't come from outer space, so it belongs to earth, human's construction.
It doesn't have to have pilots, it can be a robot machine, this is to say, controlled by humans.
I saw videos from Russian military, their technology goes practically hand to hand with America's. They have a war airplane in rescue mission, the airplane almost the size of a Hercules open the back door in the middle of the ocean, troops can get inside thanks to the airplane submerging itself to facilitate the rescue. After closing the door, it elevates itself in vertical direction, starts the other motors and leaves at full speed. Others can imitate that, but the original idea is theirs.
I won't underestimate Russian technology and their advances, which again, are as good as ours.
