[Retric]

They never suggested the first time you would hear it was the aircraft was already past you.

However, the maximum difference in angle between it’s current location and the location the sound comes from is just after it flew past you.

[bernulli]

The title is "How far behind a plane is its noise?" It's not. It's ahead of the aircraft.

[Retric]

The noise is always pointing behind the aircraft or any moving object due to lag.

Light also encodes the direction to an objects past location, even though light is always moving faster than the object.

[bernulli]

> The noise is always pointing behind the aircraft or any moving object due to lag.

I don't know what a pointing noise is.

> Light also encodes the direction to an objects past location, even though light is always moving faster than the object.

Yet the light is never outrun by the object, much like the subsonic plane never outruns its noise. However, here, the (fast) noise arrives after the (slow) plane. In your analogy, that would correspond to the (slow) object arriving before the (fast) light.

[Retric]

The direction of propagation is the way sound and light point to something. It’s why people listen to music in stereo rather than mono which sounds weird and also why telescopes work. Again simplified, but when you hear a sound with your right ear before the left that tells you something.

> arrives after the (slow) plane

That has nothing to do with the article, just your misunderstanding of what was described. At every instant in time the sound you hear corresponds to something produced by the aircraft at a specific moment in the past. Thus when someone is listing right now they hear a specific sound not the aircraft taking off.

Light from an aircraft also takes time to arrive. It might not seem relevant because of the speeds and distances involved, but the exact same thing is happening and it is relevant for light in other contexts.