Aviation Videos | Planespotting | Edits on Instagram: "To the naked eye, an aircraft’s exhaust is invisible — but that doesn’t mean it isn’t there. On one side of this video, you’re seeing a normal view of an aircraft engine where the exhaust blends seamlessly into the surrounding air. On the other, Schlieren imaging and infrared thermography reveal what our eyes can’t detect: shock waves, pressure changes, and hot exhaust gases flowing away from the engine. Schlieren techniques visualize change