in the 80s and 90s iv seen lots of aircraft that hade shiny engine covers which looked like mirrors and evrything shined off them and they looked awsome . Today thier are no airlines which have shiny engine covers and usualy go with white engine covers or with thier livery . I just don’t understand why thier are no shiny engine covers today it seems like they went out of style or somthing . iv seen A300s with shiny engine covers but thier all gone now , b-747s and b-707s had shiny engine covers but thier all gone . My gues is that the manufacturer of thos engines went bankrupt and stoped making shiny engines , but i don’t really know for shure . Can you explain why they are all gone today ?
What you are actually seeing are the nacelles. The engines are inside of these.
It’s more than likely maintenance and aesthetic reasons that the nacelles are painted. Maintenance because the metal is protected. Aesthetic because it’s just looks nicer to have the engine coordinate with the fuselage.
Today’s aircraft have nacelles or cowling made from many different materials. Some newer materials such as composite and uncladded aluminum cannot be polished and must be protected from corrosion and weather with a paint system. Airbus uses a lot of this type of aluminum and that’s why they are almost always covered with paint. Many Boeing aircraft use a lot of composite panels and also must be painted.