An aircraft that has the right of way shall maintain its speed and heading, but nothing in these rules shall relieve the pilot from the responsibility of taking such action as will best to avert a collision. An aircraft obliged to keep out of the way of another shall avoid passing over, under, or crossing ahead of it unless passing well clear.
Two aircraft approaching head-on or approximately so, shall alter their heading to the right.
When two aircraft are converging at approximately the same altitude the one that has the other on its right shall give way, except:
• power-driven heavier-than-air aircraft shall give way to airships, gliders and balloons;
• airships shall give way to gliders and balloons;
• gliders shall give way to balloons;
• power-driven aircraft shall give way to aircraft which are seen to be towing other aircraft or objects.
An aircraft being overtaken has the right of way. The overtaking aircraft, whether climbing, descending or in horizontal flight, shall keep out of the way by altering its heading to the right. No change in the relative position shall absolve the overtaking one from this obligation until it is entirely past and clear.
Note: An overtaking aircraft is one that approaches another one from the rear at an angle of less than 70°.
An aircraft in flight or operating on the ground shall give way to an aircraft landing or on final approach.
When two or more aircraft are approaching an airport, those at higher altitude shall give way to the lower one, but the latter shall not take advantage of this rule to cut in front of an aircraft on final approach, or to overtake that one.
An aircraft aware that another is compelled to land shall give way to that one.
Right of Way – On Ground
In case of danger of collision between two aircraft taxiing, the following shall apply:
• When two aircraft are approaching head on, or approximately so, each shall stop or where practicable alter its course to the right so as to keep well clear.
• When two aircraft are on a converging course, the one which has the other on its right shall give way.
• An aircraft which is being overtaken by another one shall have the right of way and the overtaking aircraft shall keep well clear of the other one.
• An aircraft taxiing on the maneuvering area of an aerodrome shall give way to aircraft taking off or about to take-off.
Source: EU-OPS