I noticed something odd. There is more heat distortion coming out of the external engine on the B747 but it should be the contrary. When heat comes out of the engine, it is exhausted so fast that it can't go up for a few feet. Only after travelling at least 20-40 feet the heat starts to be visible a little bit higher.
The heat that goes out of the engine that is close to the fuselage has already travelled under the wing and then can go up after the wing.
So currently the logic is inverted, at least on the B747. I have not checked for the other planes.
I changed some values in the 'hdr.glsl' file in the 'shaders' folder, and everything is now clear: the shader is not on the correct position on the B747.
Furthermore, when we zoom out and thus when the plane is far, the heating effect is way to present and massively distorts visually the area around the engines and the fuselage. Usually, when the plane is flying, we should not see any distortion around the plane but more a long cone behind the engines.