Silent triangular craft seen flying over Raleigh

My wife and I were walking in our neighborhood and noticed a triangle of lights flying silently in the same direction we were waking (southeast). There were three solid warm white lights at the corners, with a red light in the center of the triangle blinking at a steady interval. I only made out the lights but my wife says she could see the outline of the craft. It was flying roughly SE before banking south. We continued to watch it fly south towards downtown Raleigh until it went out of view beyond the tree line. Another regular looking aircraft was present flying in a normal northward flight path. Other aircrafts were seen in the area after, but none seemed unusual and all were in typical flight paths for this area. There is generally a lot of air traffic in this area. Observers were two mid-30s adults who are working professionals. We were able to record a video of the craft, though it was difficult to see the details in the video. We are not interested in releasing the rights to this footage at this time.