THE PLT HAD NOT FLOWN ACTIVELY FOR APRX 1 YR. HOWEVER, SHORTLY BEFORE THE ACCIDENT, HE HAD TOLD FRIENDS THAT HE HAD MISSED FLYING & WAS GOING TO RESUME THIS ACTIVITY. HE RECEIVED A CHECKOUT IN THE CESSNA 177RG ON 12/12/82 IN ANTICIPATION OF FLYING AGAIN. THIS WAS THE LAST RECORD OF THE PLT'S FLT ACTIVITY THAT WAS FOUND. AT APRX 1815 CST ON 4/13/83, HE ARRIVED AT THE ARPT & TOLD SEVERAL PEOPLE HE WAS GOING FOR A REFRESHER/PLEASURE FLT. HE TOOK OFF AT 1840 (21 MIN AFTER OFFICIAL SUNSET). ABOUT 15 MIN LATER, WHEN THE PLT TERMINATED RADAR SERVICE, HE REPORTED THAT HE HAD A SEVERE CASE OF VERTIGO & INDICATED HE WOULD RETURN TO THE DEPARTURE ARPT. A SHORT TIME LATER, SAID HE MAY NEED MEDICAL ATTENTION. HE THEN STATED THAT HE MAY NOT BE ABLE TO GET TO THAT ARPT & WAS EXPERIENCING 'BLIND SPOTS' & A 'FAST HEART BEAT.' SUBSEQUENTLY, THE ACFT CRASHED INTO THE MIDDLE OF A ROW OF CONCRETE SILOS AT NIGHT. NO PREIMPACT,MECHANICAL FAILURE WAS EVIDENT. REPORTEDLY, THE PLT HAD RECENT FAINTING SPELLS, HAD A HISTORY OF DEPRESSION.