UNABLE TO EXTEND NOSE GEAR; PA44 LANDS ON MAIN GEAR ONLY.

Narrative

ON OUR SECOND TOUCH AND GO (THIRD GEAR RETRACTION OF THE FLT) I HEARD AND FELT A CLUNK AT MY FEET AS THE GEAR CAME UP. I HAD JUST FLOWN A DEMO TFC PATTERN AND LNDG AND GAVE THE CTLS TO MY STUDENT; ON THE UPWIND. WHEN HE LOWERED THE GEAR ON THE DOWNWIND I OBSERVED NO NOSE GEAR IN THE MIRROR AND A DARK NOSE GEAR INDICATOR. WE EXITED THE TFC PATTERN ON THE R DOWNWIND FOR RWY 32 AND BEGAN TROUBLESHOOTING. I HAD MY STUDENT RAISE AND LOWER THE GEAR AGAIN; I SWAPPED LIGHT BULBS AND CHKED CIRCUIT BREAKERS; BUT IT WAS OBVIOUS FROM THE MIRRORS THAT ONLY THE NOSE GEAR DOOR WAS DOWN. I HAD MY STUDENT RAISE THE MAINS FOR OUR CLB. I HAD MY STUDENT EXECUTE THE MANUAL GEAR EXTENSION CHKLIST WHILE I FLEW LEVEL. WHEN THE NOSE GEAR DIDN'T COME DOWN I CONTACTED TWR AND INFORMED THEM OF OUR SITUATION. I THEN CONTACTED OPS. MAINT WAS ALSO MONITORING THE SITUATION AND THE CONSENSUS FROM MAINT WAS THAT I SHOULD TRY TO BRING THE NOSE GEAR DOWN WITH CENTRIFUGAL FORCE. I CLBED TO AROUND 12000 FT. BEFORE INITIATING THE FIRST DIVE; I PULLED THE HYD PUMP PWR CIRCUIT BREAKER AND HAD MY STUDENT PUT THE GEAR SELECTOR DOWN AND UNGUARD THE MANUAL KNOB. I INITIATED A DIVE AND PULL-UP AND HAD MY STUDENT PULL THE KNOB WHEN WE WERE JUST UNDER 100 KTS. BUT BY THAT TIME WE WERE VERY NOSE HIGH IN A ZOOM WITH ALMOST NO LOAD ON THE AIRPLANE. AGAIN; ONLY THE MAINS INDICATED DOWN AND I COULD ONLY SEE THE NOSE GEAR DOORS DOWN. I LEFT THE GEAR IN THIS POS AND INITIATED A SERIES OF DIVES AND PULL-UPS BUT ONLY MANAGED TO STALL THE AIRPLANE AS THE ENERGY BEGAN BLEEDING OFF. (IN HINDSIGHT; I NEVER FELT MUCH G-LOAD IN ANY OF THE PULL-UP MANEUVERS. I FEEL I WAS WRONG FOR NOT TRYING A THIRD MANUAL GEAR EXTENSION WHILE IN A 60 DEG BANKED TURN. I THINK I COULD'VE LOADED UP THE PLANE BETTER AND WISHED I WOULD'VE THOUGHT OF IT IN THE AIR.) I DID A LOW PASS SO THAT TWR COULD HAVE A LOOK. THEY ALSO INFORMED ME THAT THE NOSE GEAR APPEARED TO BE UP. OPS ASKED ME IF I WAS COMFORTABLE LNDG ON THE MAINS WITH BOTH ENGS OFF/PROPS FEATHERED; BUT TOLD ME IT WAS MY OPTION TO JUST PUT THE AIRPLANE DOWN ON ITS BELLY PWR-ON. I TOLD HIM THAT A PWR-OFF LNDG ON THE MAINS WAS NO PROB. I HAD MY STUDENT UNCOVER THE HANDLE FOR THE EMER EXIT AND I OPENED THE DOOR ON FINAL. I INITIATED A SLIGHTLY HIGH APCH THEN PULLED BOTH THROTTLES TO IDLE; FOLLOWED BY BOTH PROPS TO FEATHER AND BOTH MIXTURES TO IDLE-CUTOFF. I TOUCHED DOWN ON THE MAINS WITH FLAPS 10 DEGS AND HELD THE NOSE OFF AS LONG AS POSSIBLE. THE AIRPLANE CAME TO A REST AT ABOUT THE 2000 FT MARKERS AFTER SKIDDING FOR SOME DISTANCE ON THE NOSE COWLING. OTHER THAN NOSE DAMAGE I ALSO OBSERVED 1 BLADE ON THE R SIDE WAS DAMAGED.