Narrative:

I departed airport VFR for a short flight to lnc. Both airports reporting MVFR with ceilings of 2;000. I entered the traffic pattern at lnc; and was turning downwind. The cloud base fell to 700 AGL and I entered the clouds. I did not descend further due to hearing a bonanza reporting base in front of me; which I could not see. I decided the safest course of action was to climb and contact approach for a pop up clearance and return to departure airport. I contacted approach and requested an IFR clearance. I was asked if I could remain VFR; which I responded negative; that I was IMC at this time. I was continuing to climb and must have gone through 4;000 ft (base of class B). I was told that I was in class B airspace; that I was cleared into class B airspace; to maintain 4;000 ft and given radar vectors for the GPS approach at [home airport]. The return and rest of approach was uneventful. At the final approach fix I was in visual conditions and cancelled my clearance and thanked the controller for his assistance.

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Original NASA ASRS Text

Title: M20J pilot reported returning to departure airport after encountering IFR conditions at his destination.

Narrative: I departed airport VFR for a short flight to LNC. Both airports reporting MVFR with ceilings of 2;000. I entered the traffic pattern at LNC; and was turning downwind. The cloud base fell to 700 AGL and I entered the clouds. I did not descend further due to hearing a Bonanza reporting base in front of me; which I could not see. I decided the safest course of action was to climb and contact Approach for a pop up clearance and return to departure airport. I contacted Approach and requested an IFR clearance. I was asked if I could remain VFR; which I responded negative; that I was IMC at this time. I was continuing to climb and must have gone through 4;000 FT (base of Class B). I was told that I was in Class B airspace; that I was cleared into Class B airspace; to maintain 4;000 FT and given radar vectors for the GPS approach at [home airport]. The return and rest of approach was uneventful. At the final approach fix I was in visual conditions and cancelled my clearance and thanked the controller for his assistance.

Data retrieved from NASA's ASRS site 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.