NTSB Identification: MIA94LA100.
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Accident occurred Friday, March 25, 1994 in ORLANDO, FL
Probable Cause Approval Date: 06/01/1995
Aircraft: BELL 206L, registration: N16705
Injuries: 4 Serious,2 Minor,1 Uninjured.

NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.

SHORTLY AFTER TAKEOFF, USING WATER/ALCOHOL INJECTION, THE PILOT NOTED THE N2 TURBINE SPEED INDICATION WENT TO THE TOP OF THE GAUGE. HE ROLLED OFF THROTTLE TO REDUCE THE N2 GAUGE READING; AT THE SAME TIME, HE LOOKED FOR A PLACE TO LAND. THE PILOT BELIEVED THERE WAS INSUFFICIENT ALTITUDE FOR AN AUTOROTATION. SUBSEQUENTLY, THE HELICOPTER TOUCHED DOWN HARD & CAME TO REST WITH EXTENSIVE DAMAGE. A POSTACCIDENT EXAM REVEALED NO PREIMPACT FAILURE OF THE AIRFRAME, FLIGHT CONTROLS, OR FUEL SYSTEM. TESTING OF THE WATER/ALCOHOL SOLUTION REVEALED 66.5% METHANOL & 33.5% WATER. SPECIFICATIONS REQUIRED 33.5% METHANOL & 66.5% WATER, BUT ALLISON ENGINE PERSONNEL SAID THE HIGH LEVEL OF METHANOL WOULD NOT HAVE AFFECTED ENGINE PERFORMANCE. DURING A POSTACCIDENT TEST, THE ENGINE OPERATED TO FULL POWER WITH NO EVIDENCE OF FAILURE OR MALFUNCTION. TESTING OF THE ENGINE INSTRUMENTS REVEALED THE N2 GAUGE WAS PROVIDING A FAULTY INDICATION. THE OTHER ENGINE INSTRUMENTS OPERATED NORMALLY AFTER THE ACCIDENT.

The National Transportation Safety Board determines the probable cause(s) of this accident to be:

THE PILOT'S FAILURE TO CROSS-CHECK A FAULTY ENGINE SPEED INDICATION WITH OTHER ENGINE PERFORMANCE INDICATIONS TO VERIFY WHETHER AN ENGINE MALFUNCTION HAD ACTUALLY OCCURRED, AND HIS FAILURE TO MAINTAIN ADEQUATE ROTOR RPM DURING AN EMERGENCY LANDING. THE PILOT'S REACTION TO THE PERCEIVED ENGINE MALFUNCTION LED TO AN UNNECESSARY REDUCTION OF ENGINE POWER AND SUBSEQUENT EMERGENCY LANDING.

Full narrative available

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