Narrative:

After being cleared for an unrestr climb VFR above 8500 ft ie, clear of class B, a cloud deck was encountered at 8700 ft. This cloud deck was not forecasted and came in rapidly. WX was forecast to be 60 scattered 150 broken 200 overcast 10 mi. In order to remain clear of clouds the climb was stop and a descent was started. However, these clouds went down to 7500 ft. Radio frequency had been switched to ZKC. I was attempting to remain VFR, but wound up in class B airspace on center frequency. I was later told an airline was given a heading change because of my situation. No near miss or dangerous action was observed. Lesson learned, I should have been on departure control frequency versus center in view of rapidly changing WX.

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Original NASA ASRS Text

Title: PLT OF AN MIL ERRONEOUSLY PENETRATED CLASS B AIRSPACE DURING DSCNT OUT OF IMC TO VFR.

Narrative: AFTER BEING CLRED FOR AN UNRESTR CLB VFR ABOVE 8500 FT IE, CLR OF CLASS B, A CLOUD DECK WAS ENCOUNTERED AT 8700 FT. THIS CLOUD DECK WAS NOT FORECASTED AND CAME IN RAPIDLY. WX WAS FORECAST TO BE 60 SCATTERED 150 BROKEN 200 OVCST 10 MI. IN ORDER TO REMAIN CLR OF CLOUDS THE CLB WAS STOP AND A DSCNT WAS STARTED. HOWEVER, THESE CLOUDS WENT DOWN TO 7500 FT. RADIO FREQ HAD BEEN SWITCHED TO ZKC. I WAS ATTEMPTING TO REMAIN VFR, BUT WOUND UP IN CLASS B AIRSPACE ON CTR FREQ. I WAS LATER TOLD AN AIRLINE WAS GIVEN A HEADING CHANGE BECAUSE OF MY SIT. NO NEAR MISS OR DANGEROUS ACTION WAS OBSERVED. LESSON LEARNED, I SHOULD HAVE BEEN ON DEP CTL FREQ VERSUS CTR IN VIEW OF RAPIDLY CHANGING WX.

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.