Narrative:

I had preflted the aircraft 4 hours earlier and did notice that the rear rotor blade was tied down. I connected the battery cart to the aircraft and got into the aircraft. I cranked the aircraft monitoring the gauges and occasionally looking outside. At 50-55% N1 the 'cdclic' moved forward and to the right, the aircraft almost simultaneously started shaking violently. I rolled the throttle off and I believe the engine shut down. This whole sequence occurred within 40 seconds, I believe. After things settled down, the paramedic came up to me and asked if I was ok, she then stabilized my neck. The nurse pulled the battery cart connector from the aircraft and called an ambulance. I didn't smell fuel and didn't get a good look of the aircraft at that time. I found out the next day that the main rotor blade that was tied down broke about 3 ft from the grip. That was the cause of the violent shaking.

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Original NASA ASRS Text

Title: A BH206 HELI PLT FAILS TO PROPERLY PREFLT THE ACFT RESULTING IN STARTING THE ENG WITH THE ROTOR STILL TIED DOWN.

Narrative: I HAD PREFLTED THE ACFT 4 HRS EARLIER AND DID NOTICE THAT THE REAR ROTOR BLADE WAS TIED DOWN. I CONNECTED THE BATTERY CART TO THE ACFT AND GOT INTO THE ACFT. I CRANKED THE ACFT MONITORING THE GAUGES AND OCCASIONALLY LOOKING OUTSIDE. AT 50-55% N1 THE 'CDCLIC' MOVED FORWARD AND TO THE R, THE ACFT ALMOST SIMULTANEOUSLY STARTED SHAKING VIOLENTLY. I ROLLED THE THROTTLE OFF AND I BELIEVE THE ENG SHUT DOWN. THIS WHOLE SEQUENCE OCCURRED WITHIN 40 SECONDS, I BELIEVE. AFTER THINGS SETTLED DOWN, THE PARAMEDIC CAME UP TO ME AND ASKED IF I WAS OK, SHE THEN STABILIZED MY NECK. THE NURSE PULLED THE BATTERY CART CONNECTOR FROM THE ACFT AND CALLED AN AMBULANCE. I DIDN'T SMELL FUEL AND DIDN'T GET A GOOD LOOK OF THE ACFT AT THAT TIME. I FOUND OUT THE NEXT DAY THAT THE MAIN ROTOR BLADE THAT WAS TIED DOWN BROKE ABOUT 3 FT FROM THE GRIP. THAT WAS THE CAUSE OF THE VIOLENT SHAKING.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.