I saw a triangle craft pass by me over head with lights shining directly down located on each corner. Triangle shape was clear.

While walking my dog early in the morning before leaving for work, I saw a triangle craft at low altitude pass over at incredible speed. This craft was completely silent. The color was impossible to tell because it was dark outside but presumably black because it was very dark. There were lights on each corner shining directly down. The craft was very big and seemed to be wider running “wing” tip to tip than it was running nose to rear though I’m not sure on any specific size. I live near the Lambert Airport and see planes going in and out of there constantly. This craft was heading in the opposite direction (North).
I’d also like to note that I’m a licensed and career aerospace mechanic here in stl. I have never seen anything like this. I wish to stay anonymous to ensure my future in the aerospace industry.