GA SMA NOSE GEAR COLLAPSE DURING LNDG ROLL.

Narrative

DURING ROLLOUT TO TXWY ON RWY 36 AT WATERBURY/OXFORD ARPT THE NOSE GEAR COLLAPSED ON OUR SMA. THERE WERE NO PRIOR INDICATIONS THAT A NORMAL SAFE LNDG COULD NOT BE ACCOMPLISHED. HOWEVER; I DID COMMENT TO MY 3 PAX 'WHAT A SINK;' TO DESCRIBE THE GREATER THAN NORMAL SINK RATE AS PWR WAS REDUCED WHEN WE PASSED OVER THE END OF THE RWY. A NORMAL FULL FLAP (30 DEG) LNDG WAS MADE; HOWEVER ON THE MAIN GEAR AND PWR REDUCED TO IDLE FOR ROLLOUT TO THE TXWY APPROX MIDFIELD. AS THE PLANE LOST SPD AND FLAPS RAISED; THE NOSE LOWERED AND CONTINUED TO DO SO UNTIL THE PROP HIT THE RWY. THE PLANE CONTINUED TO SLIDE ON ITS NOSE DOWN THE RWY ABOUT 1500-2000' FROM T/D. AFTER SHUTTING OFF MASTER AND FUEL SELECTOR I INSTRUCTED MY 3 PAX TO GET OUT AS QUICKLY AS POSSIBLE. FORTUNATELY; THERE WERE NO INJURIES OR FIRE. THERE WAS NOT PRIOR WARNING OF PENDING GEAR FAILURE. I HAD PERFORMED THE PRELNDG CHK TWICE--UPON ENTERING DOWNWIND AND AGAIN AFTER TURNING FROM BASE TO FINAL. ALL INDICATIONS WERE POSITIVE--GEAR POSITION LIGHT WAS GREEN; VISUAL CHK OUT THE WINDOW SHOWED THE GEAR DOWN AND IN THE PROPER POS. AT NO TIME DID THE GEAR WARNING HORN SOUND. UPON EXITING THE PLANE ALL GEAR DOORS WERE FOUND OPEN; AND IT APPEARED THE NOSE GEAR WAS IN THE FULL UP POS AND THE PLANE HAD SLID ON THE OPEN NOSE GEAR DOORS. AFTER THE PLANE WAS REMOVED FROM THE RWY ONE OF THE ACFT MECHS SAID; 'DID YOU KNOW THAT THE GEAR HANDLE WAS IN THE UP POS?' I SAID I DIDN'T KNOW THIS AND SPECULATED THAT IT MIGHT HAVE BEEN KICKED UP AS WE WERE HURRIEDLY EXITING THE ACFT. THIS ACFT IS A 19XX SMA; WHICH HAS A REPUTATION (ALONG WITH MANY NEWER MODELS) OF GEAR DOOR/LNDG GEAR PROBS. THEREFORE; I HAVE LONG PAID SPECIAL ATTN TO DETAILED TKOF AND LNDG CHKS. I HAVE OWNED AND FLOWN THIS PLANE SINCE 1979 AND HAVE EXPERIENCED PROBS WITH GEAR DOORS NOT CLOSING IN YRS PAST. THE ANNUAL INSPECTIONS HAVE BEEN DONE AT YEAR END (NEXT DUE 1/89). ALTHOUGH THE GREEN LIGHT SHOULD INDICATE THE GEAR IS ALL DOWN AND LOCKED; THERE IS NO LIGHT TO INDICATE THE DOORS ARE CLOSED. THIS IS INDICATED ONLY BY THE GEAR HANDLE BEING IN THE DOWN/NEUTRAL POS. I AM SURE IT WAS--ESPECIALLY AFTER 2 PRELNDG CHKLIST. AT THIS WRITING THE FAA INSPECTORS WANT TO CYCLE THE GEAR TO SEE WHY THE NOSE GEAR DIDN'T EXTEND AND WHY THE HANDLE WAS UP.