What was found
SELECTED GEAR UP ON TAKEOFF, GEAR FAILED TO RETRACT, INDICATION SHOWED 3 GREEN 1 RED UNLOCK LIGHT . SELECTED GEAR DOWN, 3 GREENS RED EXTINGUISHED, ACCOMPLISHED AIR TURN BACK AND LANDED SAFELY. ACTUATED EMERGENCY GEAR EXTENSION HANDLE, RESTORED AND SERVICED PNEUMATIC BOTTLE IAW CESSNA 560XL MM CHAPTER 12-13-01. JACKED AIRCRAFT, CYCLED GEAR NUMEROUS TIMES, SYSTEM OPS CHECKED GOOD, MAINTENANCE PERFORMED IAW CESSNA 560XL MM CHAPTER 32-30-00.