the helicopter has the right of way since the fixed-wing airplane is more manuevable. Heli have the right of way over airships. A/c who declare an emergency have right of way over everything.

In visual conditions, regardless of being IFR or VFR, it is the responsibility of ALL pilots to see-and-avoid other aircraft. in Class E airspace below 10000 MSL there could be a Piper cub without an electrical system cruising along at 85 KIAS with no transponder. That 744 on an IFR flight plan might be descending. Everyone is 100% completely legal considering the airspace, altitudes, VMC, etc. The 744 won't get any TCAS alert or RA since the Cub doesn't have a transponder (note, I fly bugsmashers myself so maybe larger jets can pick up other a/c on other systems). Further, say the radar is down in the area for maintenance, the ONLY way to avoid a collision is see-and-avoid. Fortunately there is lots of air above the ground. In the US there's about 8 mid-airs each year. Not too bad considering there are 10000 commericial a/c and about 250000 general aviation aircraft. Those commercial jets are only a tiny subset of aviation despite what people think.

Note, in Instrument Conditions (IMC) or in Class A airspace where all A/C have to be on IFR flight plans, ATC has the responsibility of a/c separation. In this regard, flying in IMC is easier as there is nothing see outside.