What was found
AFTER T/O, GEAR WOULD NOT RETRACT WITH GEAR HANDLE IN UP POSITION. RECYCLED HANDLE ONCE AND GEAR STILL WOULD NOT RETRACT. ELECTED TO LEAVE GEAR DOWN. NEVER GOT AN UNLOCK LIGHT. SHORTLY BEFORE LANDING, EMERG BLEW "BLOW DOWN" BOTTLE AS A SAFETY PRECAUTION. JACKED A/C. ATTEMPTED GEAR CYCLE AND FOUND GEAR INOP. T/S GEAR CONTROL SYSTEM. REMOVED GEAR CONTROL HANDLE AND FOUND DEBRIS INHIBITING GEAR HANDLE SWITCH OPERATION. CLEANED DEBRIS FROM GEAR HANDLE SWITCHES. INSTALLED GEAR CONTROL HANDLE. PERFORMED GEAR OPS CHECK. L/G OPS CHECK GOOD. DOWNJACKED A/C. RESET AND SAFETIED GEAR NITROGEN BOTTLE. SERVICED EMERG GEAR NITROGEN BOTTLE. WORK PERFORMED REF, CE560XL MM CHAP 12-13-01, 32-01-00 AND 32-30-01.