Black Triangle

I was outside on my deck and noticed a black V like triangle and thought it was birds just flying in a V shape. It was low enough that I thought to myself why can’t I hear them?! The more puzzled I became the faster it flew and said to myself “birds cannot fly that fast!” I got up to chase it and it disappeared, I wasn’t quick enough to get a second look as it flew over the roof of the house. I also thought to myself birds fly out of position and this just remained in its exact shape. No sounds, engine noise, pure silence.