A BE58 PLT HAS TO DO A MANUAL GEAR EXTENSION AFTER IT FAILED TO LOWER WITH THE GEAR HANDLE.

Narrative

ON THE COLDEST NIGHT OF THE SEASON; (-28 DEGS C TO 6000 FT) UPON REACHING A BUMPY DOWNWIND; AT THE USUAL TIME; I SELECTED GEAR DOWN AT 160 MPH; 15 MPH BELOW VLE. ODDLY ENOUGH; NOTHING HAPPENED; NO GEAR NOISE; ELECTRIC LOAD AND NO GEAR LIGHTS. I INITIALLY TRIED ONCE MORE WITH SAME RESULTS; SO CLBED UP TO A SAFE ALT AND REACQUIRED FLT FOLLOWING WITH BOSTON APCH. I WORKED ON THE PROB FOR A WHILE AT 3500 FT AND DECIDED MANCHESTER ARPT A BEST CHOICE FACILITY TO DIVERT TO FOR AT BEST AN EMER/MANUAL GEAR EXTENSION. UPON ARR OVER MHT AT 5500 FT AND TALKING WITH MHT APCH; I RAN THE MANUAL EXTENSION PER THE AFM AND COMPANY CHKLIST WITH NO PROB. UPON ATTAINING 3 GREEN AND NO 'RED' PER THE AFM; I LANDED WITHOUT INCIDENT AND LEFT THE AIRPLANE OVERNIGHT FOR MAINT. AT LAST COM WITH COMPANY AFTER JACKING THE ACFT AND DOING NUMEROUS INSPECTIONS AND 'GEAR SWINGS;' NO PROB WAS FOUND. THE PREVIOUS CREW; HOWEVER; DID INFORM ME AT A LATER DATE THAT SHE HAD DONE PRACTICE EMER GEAR EXTENSIONS ON THE PREVIOUS FLT. IT'S DOUBTFUL THAT HAD CAUSED MY PROB; ALTHOUGH THE TIMING IS SUSPECT. BEING ONLY 12 DEGS FROM THE AFM'S LIMIT AND THE COLDEST DAY OF THE PAST 50 YRS IS MORE LIKELY THE CULPRIT.