A BEECH 55 LANDED WITH THE R MAIN LNDG GEAR STILL RETRACTED WITH LNDG GEAR POS LIGHT GREEN INDICATING ALL GEAR DOWN AND LOCKED.

Narrative

UPON LNDG; INITIALLY THOUGHT WE BLEW A TIRE; THEN IT APPEARED THE GEAR COLLAPSED (RIGHT MAIN). PROP STRIKE ENGINE STOPPED. WE EXITED THE ACFT (2 SOULS ON BOARD) AND FOUND THE R MAIN GEAR TO STILL BE IN THE HOLE; IT NEVER EXTENDED. I HAD A GREEN GEAR LIGHT DURING THE ENTIRE APCH AND ALSO ON THE GND; THIS WAS VISUALLY VERIFIED BY THE FIRE DEPT PERSONNEL. SUSPECTED CAUSE OF THE PROB WAS A GEAR BOX FAILURE. THE GEAR (GREEN) LIGHT ON THIS MODEL BARON WORKS ON THE CAM ON THE GEAR BOX; GEAR MUST HAVE JAMMED IN THE WELL. AS THE MOTOR TURNED THE GEARS IN THE GEARBOX FAILED; BUT THE CAM TURNED AND GAVE ME A GEAR DOWN AND LOCKED INDICATION. THERE IS ONLY ONE GREEN LIGHT TO INDICATE A GEAR SAFE CONDITION. NO INJURIES; ACFT VEERED OFF THE RWY AND TURNED 180 DEGS ONTO THE GRASS. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE FAILURE OF THE R MAIN LNDG GEAR TO EXTEND WAS CAUSED BY A FROZEN UPLOCK ROLLER. THE RPTR SAID THE SEQUENCE OF THE LNDG GEAR EXTENSION IS AS FOLLOWS: LNDG GEAR ELECTRIC MOTOR PWRS A GEARBOX DRIVING ROD ARMS TO UNLOCK L; R AND NOSE GEAR UPLOCK ROLLERS. THE RPTR SAID THE R ROD ARM WAS FOUND BENT DUE TO THE UPLOCK ROLLER FAILING TO MOVE. THE RPTR STATED WHEN THE MOTOR DRIVEN GEARBOX DROVE THE ROD ARMS TO UNLOCK THE LNDG GEAR IT ROTATED A CAM WHICH OPERATED A MICROSWITCH TURNING ON THE GREEN LNDG GEAR POS LIGHT. THE RPTR SAID AT THIS POINT THE GREEN POS LIGHT WAS ILLUMINATED; BUT THE LNDG GEAR WAS UNSAFE. THE RPTR SAID THIS IS A DESIGN DEFICIENCY THAT MUST BE CORRECTED. THE RPTR STATED THE ACFT INCURRED DAMAGE TO THE R WING TIP; FLAP; AILERON; PROPELLER AND REQUIRES AN ENGINE TEAR DOWN.