Narrative:

Captain (PF) told first officer (PNF) to advise approach that we would need runway 31L or runway 31R at mdw. First officer did so and we were told runway 4R or return to rfd. Captain went to company frequency and came back saying all was well and he would shoot the approach. First officer realized later that captain was 'going ahead' rather than that captain's 'high minimums' were not a factor. That is, first officer believed captain had learned something 'off frequency' that made the approach legal, or that he was out of 'high minimums' experience level.

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Original NASA ASRS Text

Title: COMMUTER SMT CONTINUED APCH LNDG IN WX REPORTED BELOW PIC'S HIGH WX MINIMUMS.

Narrative: CAPT (PF) TOLD F/O (PNF) TO ADVISE APCH THAT WE WOULD NEED RWY 31L OR RWY 31R AT MDW. F/O DID SO AND WE WERE TOLD RWY 4R OR RETURN TO RFD. CAPT WENT TO COMPANY FREQ AND CAME BACK SAYING ALL WAS WELL AND HE WOULD SHOOT THE APCH. F/O REALIZED LATER THAT CAPT WAS 'GOING AHEAD' RATHER THAN THAT CAPT'S 'HIGH MINIMUMS' WERE NOT A FACTOR. THAT IS, F/O BELIEVED CAPT HAD LEARNED SOMETHING 'OFF FREQ' THAT MADE THE APCH LEGAL, OR THAT HE WAS OUT OF 'HIGH MINIMUMS' EXPERIENCE LEVEL.

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.