Narrative:

On VFR flight plan from boi to rdm at 10500 ft. Encountered moderate continuous rain, descended to 10000 ft and asked ZSE (who I had been flight following with VFR) for an IFR clearance as conditions were deteriorating to IMC and I did not believe I could get under WX. Myself and aircraft both IFR rated. I told center I was encountering 'inadvertent IMC' to expedite an IFR clearance which I promptly received. I should have asked earlier center (slc) for an IFR clearance instead of waiting for the handoff to seattle. After advising ZSE that I had a VFR flight plan on file and asked for an IFR clearance, I did not close the VFR flight plan with mcminnville after landing, although I did close out with ZSE on the IFR 10 mi east of rdm.

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Original NASA ASRS Text

Title: GOV PLT OF AN SMT TWIN ENTERED IMC ON A VFR FLT PLAN AND SUBSEQUENTLY FAILED TO CLOSE HER VFR FLT PLAN.

Narrative: ON VFR FLT PLAN FROM BOI TO RDM AT 10500 FT. ENCOUNTERED MODERATE CONTINUOUS RAIN, DSNDED TO 10000 FT AND ASKED ZSE (WHO I HAD BEEN FLT FOLLOWING WITH VFR) FOR AN IFR CLRNC AS CONDITIONS WERE DETERIORATING TO IMC AND I DID NOT BELIEVE I COULD GET UNDER WX. MYSELF AND ACFT BOTH IFR RATED. I TOLD CTR I WAS ENCOUNTERING 'INADVERTENT IMC' TO EXPEDITE AN IFR CLRNC WHICH I PROMPTLY RECEIVED. I SHOULD HAVE ASKED EARLIER CTR (SLC) FOR AN IFR CLRNC INSTEAD OF WAITING FOR THE HDOF TO SEATTLE. AFTER ADVISING ZSE THAT I HAD A VFR FLT PLAN ON FILE AND ASKED FOR AN IFR CLRNC, I DID NOT CLOSE THE VFR FLT PLAN WITH MCMINNVILLE AFTER LNDG, ALTHOUGH I DID CLOSE OUT WITH ZSE ON THE IFR 10 MI E OF RDM.

Data retrieved from NASA's ASRS site as of July 2007 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.