The triangle shape with no sound.

At the time i was approx: 13-14 years old my parents and myself had gone to a local club,at approx: 22:30 i went outside where their was a football/rugby field i remember they was still erecting the outside lighting for the field,and at this time it was a pitch black night with no moon. I wondered onto the field itself and was generally looking around when i noticed three lights in the sky heading roughly in my direction i thought it strange that they was not flashing strobe lights as you would find on all commercial aircraft,and to add to it their was no sound either, which did strike me as very strange, i kept watching this what looked triangle shape judging by the three lights, at each end,as it flew over my head approx: 300ft up. The three lights were colured red, blue, green.they stayed on without any flashing at all, i remember looking around the field area to see if anybody else was watching but they wasnt anybody around,I will always remember that it was totally silent, as it moved away, turned sharply then the three coloured lights just dissappered, i tried looking for them to reappear, but could see nothing.
Date in September 1984 is approximate.  PD