We frequently holiday in Mallorca and more often than not see a strange light display on the odd airliner coming overhead, This is something like 2 octagonal light formations on the underside of the aircraft. Does anyone know anything about this?
Any aircraft must have these lighting systems:
Now what you saw must be a combination of all of the above. Some aircraft look like a moving party at night, I remember the MD90s for example having a funny lights system if all lights are on.