Robinson R22
Air Traffic Control Fully Certified
Communication Breakdown
ATC Issue All Types; Conflict Airborne Conflict
Air Traffic Control Issued New Clearance
Human Factors
A helicopter was on an IFR flight plan. He was at 6;000 and on a heading to join the ILS27 at his destination. A Piper was eastbound along the coastline to the east. He had been told to maintain at or above 3;500. I observed him at 4;400 FT and a short time later I saw him climbing through 5;300. I told him to stop at 5;500 and called the traffic. He then continued to climb; reaching 5;900 FT when the targets merged. My Trainee was calling traffic when I took over and turned the helicopter to the south. The pilot should have told us if he couldn't maintain his assigned altitude.
TRACON Controller described a conflict where a VFR traffic failed to adhere to assigned VFR altitude/s.