Narrative:

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.

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Original NASA ASRS Text

Title: TRACON Controller described a conflict where a VFR traffic failed to adhere to assigned VFR altitude/s.

Narrative: 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.

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.