It was huge , black , with lights and totally silent and triangle shaped

My son who at the time was 9 or 10, and i came out of the hockey arena and headed up the short, steep hill so I could take him home from hockey.  I have an older son who also played numerous games at the same rink.  I traveled the road hundreds of times.  The road is steep enough so that you literally have a perfect look at the sky.  I remember it was a clear evening , almost dark.  So i could see the sky perfectly.  
Thats when i saw that the stars were disappearing.  I saw a huge Black triangle shape with different color lights on the bottom.  I estimated it at over 1000 feet long ,I stopped the car , got my son out of the car, before I told him what I saw.   And asked him what He saw.  Exactly the same answer.   
What blew me away was , it did not make a sound.  It moved WNW what I figured was about 40 - 50 MPH.  He even told me the different colors of light.  I know what I saw because I asked my son and he saw what i saw.  I said nothing to him except asked him exactly what he saw.  His last question to me was, what was that dad .
Witness indicates that the date of the sighting is approximate.  PD