Originally Posted by
Fl1ingfrog
For exam technique: whenever a "constant bearing" is in the question then you must be on a collision course. Look at the question again to see if the question is regarding a 'collision' course or whether it is asking who has the 'right of way'.
Constant bearing of 90 degrees, both aircraft at same speed and heading. Are they on a collision course? Substitute any bearing you like - are they on a collision course? I suggest that you must get very nervous watching aircraft fly in formation.