Narrative:

I was flying south over marin county at 3500 feet with flight following enroute to sql. I requested a transition over sfo (class B) and was cleared at or below 2000 feet. A few miles north of sfo airspace I noticed a cloud deck at about 2000 feet a few miles ahead. I had only a short time before entering class bravo and got rushed a bit. I decided to descend below the clouds to comply with the 2000 foot altitude restriction. As I got lower; so did the base of the clouds and I entered them at about 1200 feet. I called sfo and requested vectors. Denied. I stopped my descent at 800 feet for safety reasons. I was still in the clouds and there was traffic in the area. I immediately began a climb to get altitude and broke into the clear in less than a minute well within the 2000 foot altitude restriction. The rest of the flight was uneventful. ATC did not request I contact them. Nonetheless; I did enter clouds while flying VFR. I ascribe this problem to the fact that things happened quickly once ATC cleared me into class B at or below 2000 feet with a cloud deck below me. I now realize I should have done one of three things: (1) I could have made a 180 degree turn to the north whence I came because conditions there were cavu and I would have had time to sort things out; or (2) called ATC and requested an oakland transition as it appeared clear of clouds to the east; or (3) asked ATC for a sfo transition at my original altitude of 3500 feet where there were no clouds.

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Original NASA ASRS Text

Title: While on a VFR flight plan; C-172 pilot encountered IMC while attempting to descend below clouds in aircraft's path. Pilot climbed out of clouds and continued in VMC.

Narrative: I was flying south over Marin County at 3500 feet with flight following enroute to SQL. I requested a transition over SFO (Class B) and was cleared at or below 2000 feet. A few miles north of SFO airspace I noticed a cloud deck at about 2000 feet a few miles ahead. I had only a short time before entering Class Bravo and got rushed a bit. I decided to descend below the clouds to comply with the 2000 foot altitude restriction. As I got lower; so did the base of the clouds and I entered them at about 1200 feet. I called SFO and requested vectors. Denied. I stopped my descent at 800 feet for safety reasons. I was still in the clouds and there was traffic in the area. I immediately began a climb to get altitude and broke into the clear in less than a minute well within the 2000 foot altitude restriction. The rest of the flight was uneventful. ATC did not request I contact them. Nonetheless; I did enter clouds while flying VFR. I ascribe this problem to the fact that things happened quickly once ATC cleared me into Class B at or below 2000 feet with a cloud deck below me. I now realize I should have done one of three things: (1) I could have made a 180 degree turn to the north whence I came because conditions there were CAVU and I would have had time to sort things out; or (2) called ATC and requested an Oakland transition as it appeared clear of clouds to the east; or (3) asked ATC for a SFO transition at my original altitude of 3500 feet where there were no clouds.

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.