ShyTorque --
Lemain, Are you not familiar with the rules of the air? I ask because you seem to be trying to put this in context of shipping.
The relevant rule says that where two aircraft are approaching head on, each turns right to avoid the other. Most pilots would instinctively turn to avoid anything ahead, especially if already at low level.
The rules also state that pilots needing to avoid should not pass directly below, or above another aircraft.
Hmmmm...Maybe I see it a bit differently as I also do marine (ocean). I do cars trains and buses as well. And bicycles. Just for the purpose of this reply, suppose I am flying directly towards you, you are on my nose. We are talking visual only. I see your white, your green and your red. And hopefully vice versa. How do I 'notice' you? I mean, what draws your presence to my attention?...