A BE76'S NOSE GEAR INEXPLICABLY COLLAPSED ON AN INSTRUCTIONAL TKOF FLT. NOSE CONE AND PROC DAMAGE RESULTED.

Narrative

ON NOV/WED/06 AT APPROX XA30; I MET WITH MY STUDENT FOR A FLT IN THE BE-76 DUCHESS. THIS WAS TO BE A 1.5 HR NIGHT FLT TO COMPLETE A LESSON IN THE COMMERCIAL; MULTI-ENG SYLLABUS. THIS WAS THE FIRST TIME THAT I HAD FLOWN WITH THIS PLT. HE IS A STUDENT OF ANOTHER INSTRUCTOR WHO ASKED IF I WOULD COMPLETE THE LESSON FOR HIM. AT THE END OF THE BRIEF; THE STUDENT STATED THAT HE STILL NEEDED TO PREFLT. HE WENT OUT TO THE AIRPLANE AND I WENT TO MY VEHICLE TO GET MY FLT BAG. WHEN I ARRIVED AT THE AIRPLANE; THE STUDENT ALREADY COMPLETED THE INTERNAL COCKPIT CHK. I PLACED MY THINGS INTO THE AIRPLANE AND DID MY OWN INTERNAL COCKPIT CHK. UPON COMPLETION OF THE CHK; I STEPPED OUT AND BEGAN TO FOLLOW THE STUDENT AROUND THE ACFT FOR THE EXTERNAL PREFLT. AT THE CONCLUSION OF THE PREFLT; WE AGREED THAT EVERYTHING LOOKED GOOD. I DID A FINAL CHK TO ENSURE THAT THE GAS CAPS AND THE ENG OIL ACCESS DOORS WERE SECURE. WE ENTERED INTO THE COCKPIT; SEAT BELTED OURSELVES IN; AND BEGAN THE ENG STARTUP CHKLIST. AFTER ENG STARTUP; WE DID THE BRAKE CHK; AND TAXIED OUT TO THE STOP SIGN ON THE TXWY NEXT TO THE NEW FLT SCHOOL PARKING AREA. WE TUNED IN ATIS AND RECORDED THE LATEST INFO. THE NEXT STEP WAS TO PERFORM THE BEFORE TKOF CHKLIST. AGAIN; THE STUDENT READ THROUGH EACH ITEM AND PERFORMED THE TASK AS I FOLLOWED ALONG WITH HIM. NEXT; WE TAXIED UP TO THE HOLD SIGN THAT WAS NEXT TO THE OLD PARKING AREA AT THE FLT SCHOOL AND CALLED GND FOR TAXI INSTRUCTIONS. AFTER GETTING CLRNC TO TAXI TO RWY 26R; WE BEGAN A TAXI TO RWY 26R AND THE STUDENT ASKED IF I WOULD LIKE A BRIEFING. I GAVE HIM A BRIEFING ON WHAT THE PROCS WOULD BE IF WE HAD AN ENG FAILURE ON THE TKOF ROLL; AND WHEN WE WERE CLBING OUT WITH BOTH WHEELS UP AND WHEELS DOWN. WE HELD SHORT OF RWY 26R AND THE STUDENT COMPLETED HIS FINAL CHKLIST AS I FOLLOWED ALONG. AFTER THE LNDG ACFT CLRED THE RWY; TWR CLRED US FOR TKOF. THE STUDENT ACKNOWLEDGED THE CLRNC AND TAXIED ON THE RWY. WHEN HE ALIGNED THE ACFT; HE THROTTLED UP; AND I CALLED OUT THAT THE DIRECTIONAL GYRO HDG WAS ALIGNED WITH THE RWY AND ALL OF HIS GAUGES WERE IN THE GREEN. I DIVIDED MY ATTN BTWN LOOKING OUTSIDE AND CALLING OUT HIS AIRSPDS. I CALLED AIRSPD ALIVE AND REDLINE. AFTER CALLING REDLINE; I BROUGHT MY ATTN BACK OUTSIDE AND THE NOSE SUDDENLY DROPPED TO THE GND. THE STUDENT YELLED OUT ASKING WHAT HAPPENED AND I TOLD HIM THAT OUR NOSE HAD HIT THE CONCRETE. I PROCEEDED TO TAKE CTL OF THE ACFT TO MAINTAIN DIRECTIONAL CTL AND LOOKED DOWN TO SEE WHAT THE STUDENT WAS DOING WITH THE THROTTLES. HE APPEARED TO FREEZE UP ON ME; SO I TOLD HIM THAT WE NEED TO BE SHUTTING DOWN. AT THAT TIME; I BEGAN THE PROCESS OF BRINGING THE MIXTURES AND THROTTLES BACK. I DO NOT KNOW WHAT THE ENGS WERE DOING AT THAT TIME (WERE THEY STILL RUNNING? OR HAD THEY STOPPED WHEN THE PROPS HIT?)BECAUSE I WAS MAINTAINING FOCUS ON KEEPING THE AIRPLANE ON THE RWY. AFTER GETTING THE AIRPLANE TO A STOP; I SHUT THE FUEL OFF; AND CALLED TWR TO TELL THEM WHAT HAD HAPPENED. THEY ASKED IF I WAS GOING TO LEAVE THE RWY. I MUST HAVE NOT BEEN CLEAR ENOUGH AS TO WHAT HAPPENED OR THEY MISUNDERSTOOD; SO I TOLD THEM THAT I WAS UNABLE TO MOVE. THEY WOULD NEED TO SEND SOMEONE OUT AND SHUT DOWN THE RWY. TWR ACKNOWLEDGED AND I TOLD THEM THAT WE WERE DEPARTING THE ACFT. NEXT; I ASKED THE STUDENT TO SHUT DOWN ALL ELECTRICS. I HEARD THE ROCKER SWITCHES BEING FLIPPED; BUT DID NOT PAY ATTN TO ENSURE EVERYTHING HAD BEEN SHUT DOWN. AFTER WE DEPARTED THE ACFT; I ASKED IF HE HAD ALSO SHUT OFF THE MAGNETOS. HE ACKNOWLEDGED THAT HE DID. AT THIS TIME; I WAS ABLE TO GET A VISUAL INSPECTION OF THE NOSE WITH THEIR HEADLIGHTS. I LOST MY FLASHLIGHT DURING THE INCIDENT. WITH THE EVENTS THAT OCCURRED; I EXPECTED TO SEE A MANGLED MESS UNDER THE NOSE; BUT FOUND THAT THE NOSEWHEEL WELL DOORS WERE PERFECTLY CLOSED AS IF THE NOSEWHEEL HAD RETRACTED INTO THE WELL. AFTER A FEW MINS; I ALSO NOTICED THAT THE L MAIN OVER-CTR BRACE WAS BEGINNING TO FOLD AS IF THE L MAIN WAS BEGINNING TO RETRACT. THE R MAIN LNDG GEAR LOOKED TO BE INTHE DOWN AND LOCKED POS. I TALKED TO THE TWR ON THE PHONE; BECAUSE THEY WANTED INFO FROM ME. THEY ALSO SAID THAT THEY CONTACTED THE FSDO AND WE HAD BEEN GIVEN AUTH TO MOVE THE ACFT.