GA SMT GEAR COLLAPSED DURING LNDG ROLL.

Narrative

ATL APCH HANDED US OFF TO PEACHTREE/DEKALB TWR AND I WAS INSTRUCTED TO FLY A LEFT DOWNWIND TO RWY 20L. I WAS APCHING FROM THE E AND HAD RECEIVED THE ATIS FOR PKD 30 MI OUT; PRIOR TO CONTACTING ATL APCH FOR FLT FOLLOWING UNDER THE TCA. ON DOWNWIND THE TWR FIRST DIRECTED ME TO EXTEND MY DOWNWIND BECAUSE OF A CONFLICT WITH AN SMA THAT WAS ON FINAL FOR RWY 20L; AND THEN ASKED IF I COULD ACCEPT RWY 20R. I ACCEPTED THE SHORTER 20R RWY AND EXTENDED MY GEAR ON THE EXTENDED DOWNWIND LEG. THE GEAR EXTENDED AND INDICATED A GREEN LIGHT. (THERE IS NOT A 3 LIGHT INDICATOR ON THIS MODEL SMT.) PARTIAL FLAPS WERE EXTENDED ON BASE LEG; AND FULL FLAPS ON FINAL. I SLOWED THE PLANE TO 100 MPH ON FINAL AND TOUCHED DOWN ON BOTH MAIN WHEELS AT 90 MPH APPROX 100' PAST THE THRESHOLD MARKERS. THE PAX IN THE RIGHT SEAT HAD RECHKED THE GEAR LIGHT AND NOSE WHEEL INDICATOR ON SHORT FINAL; AND HAD OBSERVED THE 90 MPH T/D SPD. A PAX IN THE REAR SEAT HAD ALSO OBSERVED MY APCH AND LNDG. AS I LOWERED THE NOSE GEAR TO THE RWY THE NOSE SETTLED TO THE RWY; THE GEAR HORN SOUNDED AND THE PLANE SETTLED TO THE RWY AND SKIDDED TO A STOP JUST SHORT OF THE FIRST TURNOFF. MY PAX EXITED FIRST AND I SHUT OFF THE FUEL; MAGS AND MASTER SWITCHES BEFORE LEAVING THE ACFT. THE GEAR SWITCH WAS IN THE DOWN POS AND BOTH PAX HAD ATTESTED TO THE FACT THAT I DID NOT INADVERTENTLY RETRACT THE GEAR SWITCH. THERE WERE 2 WITNESSES TO MY LNDG WHO HAD OBSERVED THE SPD AND THE NOSE GEAR FAILURE. I BELIEVE THAT THE NOSE GEAR DID NOT LOCK IN LNDG POS EVEN THOUGH WE HAD A GREEN LIGHT. THERE IS ONLY ONE LIGHT ON THIS YEAR SMT AND I BELIEVE AN ADDITION OF A 3 LIGHT INDICATOR MAY HAVE INDICATED THIS KIND OF MALFUNCTION. THE SMT HAD A NUMBER OF INOP SYSTEMS WHICH INCLUDED THE AUTOPLT AND THE ALTIMETER APPEARED TO READ 100' HIGH; THE D/G PRECESSED ABOUT 20 DEGS PER 15 MINS AND THE LEFT ENG WAS DIFFICULT TO SHUT DOWN EVEN IN THE IDLE CUT-OFF POS. THE FLAP SWITCH IS UNDER THE CONTROL WHEEL ON THE PLT'S SIDE AND HAD NO INDICATOR OR DETENT POS. IT WAS NECESSARY TO OBSERVE THE PHYSICAL FLAP POS IN ORDER TO SET PARTIAL FLAPS. FULL FLAP OR FLAP RETRACTED POSITIONS WERE CTLED BY A MICRO SWITCH. THE FAA AND OWNER HAVE INDICATED THAT I MUST HAVE MOVED THE GEAR SWITCH TO THE UP POS ON LNDG. HOWEVER MY 2 PAX; ONE A FORMER PLT; THE OTHER A BOAT CAPT; BOTH HAVE DISPUTED THAT FACT. IN ADDITION; THERE IS A SAFETY SWITCH THAT DISABLES THE GEAR SWITCH IF THE PLANE IS ON THE MAIN GEARS. I HAVE FLOWN PRIMARILY HIGH PERFORMANCE RETRACTABLE TWINS FOR THE LAST 15 YRS AND I AM POSITIVE THAT THE INCIDENT WAS CAUSED BY A MECHANICAL FAILURE IN THE GEAR RETRACTION SYS.