I was never a Snowbird as such, just a line Instructor Pilot that did a real job, ha!

The 2 tanks - an add on modification just for the demonstration team birds - under the belly, hold engine oil that is simply pumped & sprayed into the hot exhaust. The pilot of course turns the smoke on/off as required. Different colours can be mixed into the oil but it is a PITA so normally they go with just white.

My father was an air force tech back in the 1970s who was on the team that designed & installed the smoke systems. He received a nice promotion due to his work on this project.

As shown on the video, they modified one of the tanks & mounted HD Cameras that enabled those great videos...

TAM