We take shortcuts all the time with our physical models. We rarely consider that wire has any resistance, for example, or that batteries have a source impedance. That’s fine up until the point that it isn’t. Take the case of the Navy’s Grumman F11F Tiger aircraft. The supersonic aircraft was impressive, although it suffered from some fatal flaws. But it also has the distinction of being the first plane ever to shoot itself down.
So here’s the simple math. A plane traveling Mach 1 is moving about 1,200 km/h — the exact number depends on a few things like your altitude and the humidity. Let’s say about 333 m/s. Bullets from a 20 mm gun, on the other hand, move at more than 1000 m/second. So when the bullet leaves the plane it would take the plane over three seconds to catch up with it, by which time it has moved ever further away, right?
