Helicopter pilot reports a near midair collision with a PA28 at 2;000 ft near pdx.

Attributes
ACN	1099811
Time
Date	201307
Local Time Of Day	0601-1200
Place
Locale Reference	7S3.Airport
State Reference	OR
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Make Model Name	A109 All Series
Operating Under FAR Part	Part 135
Flight Phase	Cruise
Route In Use	Direct
Flight Plan	VFR
Aircraft 2
Make Model Name	PA-28 Cherokee/Archer/Dakota/Pillan/Warrior
Operating Under FAR Part	Part 91
Flight Phase	Descent
Person 1
Function	Pilot Flying Single Pilot
Qualification	Flight Crew Instrument Flight Crew Flight Instructor Flight Crew Commercial
Experience	Flight Crew Last 90 Days 21 Flight Crew Total 6500 Flight Crew Type 1200
Events
Anomaly	Conflict NMAC
Miss Distance	Horizontal 100 Vertical 100

Narrative:

We were in cruise flight at 2;000 ft AGL; ceiling at 3;000 ft at approximately 140 KTS. Aircraft appeared to be a piper cherokee on an opposing course directly ahead on a slightly offset course descending from the cloud cover. The aircraft was completely white in color. I spotted aircraft above at approximately 500 ft ahead and by the time I took evasive action we were in the proximity listed above. Evasive action was taken by me. At the last second the cherokee appeared to turn right and away from us and pulled up as we turned right and descended. I was not yet talking with ATC due to my position and altitude to the other uncontrolled fields nearby. I was monitoring both of those frequencies and they were not on either of the frequencies. We continued on course. If I had TCAS in this aircraft this encounter probably would have not happened.

Original NASA ASRS Text

Title: Helicopter pilot reports a NMAC with a PA28 at 2;000 FT near PDX.

Narrative: We were in cruise flight at 2;000 FT AGL; ceiling at 3;000 FT at approximately 140 KTS. Aircraft appeared to be a Piper Cherokee on an opposing course directly ahead on a slightly offset course descending from the cloud cover. The aircraft was completely white in color. I spotted aircraft above at approximately 500 FT ahead and by the time I took evasive action we were in the proximity listed above. Evasive action was taken by me. At the last second the Cherokee appeared to turn right and away from us and pulled up as we turned right and descended. I was not yet talking with ATC due to my position and altitude to the other uncontrolled fields nearby. I was monitoring both of those frequencies and they were not on either of the frequencies. We continued on course. If I had TCAS in this aircraft this encounter probably would have not happened.

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.