A C414 PLT RAISED THE GEAR PREMATURELY DURING A TOUCH-AND-GO. AN ABORTED TKOF FOLLOWED WITH THE GEAR COLLAPSING.

Narrative

ON ROTATION DURING OUR 5TH TOUCH-AND-GO; THE NOSE DROPPED ABRUPTLY AND BOTH PROPS STRUCK THE RWY. REACTING TO THE NOSE DROP; I PULLED UP HARDER AND NOW FOUND MYSELF AIRBORNE WITH 2 DAMAGED PROPS/ENG VIBRATION AND GEAR IN TRANSIT; APPROX 30-40 FT AGL; WITH APPROX 3500 FT RWY REMAINING. I CLOSED THE THROTTLES; PUT THE GEAR HANDLE DOWN AND ABORTED THE TKOF. THE GEAR DID NOT FULLY EXTEND PRIOR TO TOUCHDOWN AND THE ACFT SLID TO A STOP -- NO INJURIES; NO FIRE; NO MAJOR AIRFRAME DAMAGE. ORIGINALLY; I THOUGHT THE NOSE GEAR HAD COLLAPSED DUE TO A MECHANICAL DEFECT; BUT ON ANALYSIS; IT APPEARS THAT THE EXPLANATION (MORE LIKELY; THIS IS...) IS THAT RATHER THAN PUTTING THE GEAR HANDLE UP AFTER ROTATION; I MAY HAVE UNINTENTIONALLY MOVED THE GEAR HANDLE TO THE UP POS AFTER ADVANCING THE MIXTURES; PROPS; THROTTLES FULL FORWARD THEN RAISING THE FLAPS. IF I HAD CONTINUED THE SEQUENCE AND MISTAKENLY RAISED THE GEAR HANDLE PRIOR TO ROTATION; THE NOSE GEAR WOULD HAVE STARTED TO RETRACT AT ROTATION. THE FACTS ON ANALYSIS LED ME TO BELIEVE I MAY HAVE RAISED THE GEAR HANDLE PREMATURELY BY MISTAKE.