BE35 PLT SUFFERS PARTIAL COLLAPSE OF RIGHT MAIN GEAR DURING LNDG ROLL.

Narrative

I RPTED L DOWNWIND AND WAS THEN CLRED TO LAND RWY 17 BY ZZZ TWR. I PERFORMED MY PRE-LNDG CHKLIST (GUMPS) AND CONFIRMED A GREEN LIGHT ON THE LNDG GEAR INDICATOR LIGHT. I COMPLETED MY APCH AND LANDED UNEVENTFULLY. AS I WAS ROLLING OUT ON RWY 17; I NOTICED MY R WINGTIP BEGAN TO DROP. I QUICKLY CONFIRMED THE GEAR HANDLE WAS DOWN AND SECURE. I THEN RAISED THE FLAPS; PULLED THE MIXTURE AND RODE THE PLANE AS IT TURNED 90 DEGS TO THE R AND CAME TO REST ON THE GRASS W OF RWY 17; ABOUT 200 FT N OF INTXN A4. I RESPONDED TO A RADIO CALL FROM TWR; CONFIRMING THAT BOTH MYSELF AND PAX WERE OK AND UNINJURED. I THEN TURNED THE MASTER OFF AND WE EXITED THE PLANE FROM THE MAIN CABIN DOOR. THE PLANE WAS RESTING ON ITS R WING; THE R MAIN GEAR WAS PARTIALLY RETRACTED; THE L MAIN AND NOSE GEAR WERE EXTENDED AND LOCKED. THERE WAS NOT A PROP STRIKE AND THE DAMAGE APPEARED TO BE MINIMAL. I CALLED TWR AND THEN THE LCL FSDO TO RPT THIS INCIDENT. AN INSPECTOR FROM THE LCL FSDO ARRIVED AND DECLARED THIS AN INCIDENT. IN OUR OPINION; IT APPEARED AS IF THERE WAS A MECHANICAL MALFUNCTION WITH THE R LNDG GEAR DURING ROLLOUT. THE ACFT WAS LIFTED BACK ONTO ITS GEAR; THE R MAIN WAS SECURED WITH A SAFETY BAR; AND THE ACFT WAS TOWED TO A MAINT HANGAR ON THE FIELD.