AFAIK the rangefinder on the targeting system is pretty good, with that data and the data of the plane (direction, altitude, velocity, etc...) getting the speed of an object is pretty trivial.
If this is indeed a bird, then you can definitely trust the sensor's data. If it's a smoke plume, something ethereal, ball lighting or anything not quite solid, the rangefinder will give false values.
If this is indeed a bird, then you can definitely trust the sensor's data. If it's a smoke plume, something ethereal, ball lighting or anything not quite solid, the rangefinder will give false values.