CHI06TA148

The helicopter sustained substantial damage when it impacted terrain following a practice autorotation and subsequent loss of engine power. The helicopter was operating as a public-use instructional flight. The pilot stated, in part, "Immediately upon reducing the throttle and lowering the collective, the engine of the helicopter stopped. This was confirmed by the indication of the "split" needles and engine RPM indicating zero RPM. This was further confirmed by the manifold pressure gauge which was rising to atmospheric pressure. This practice autorotation had turned into a real total loss of engine power autorotation to touchdown. ... [After touchdown,] the main rotor blade flex downward and came in contact with the tail boom section causing the tail rotor to separate." Wind in the area was 220 degrees at 13 knots gusting to 19 knots. An examination of the wreckage revealed no preimpact anomalies. The engine was operational during a subsequent test run.

On June 6, 2006, about 1750 central daylight time, a Schweizer 269C helicopter, N54LC, operated by the Lake County Sheriff's Department, sustained substantial damage when it impacted terrain following a practice autorotation and subsequent loss of engine power near Schererville, Indiana. The helicopter was operating as a public-use instructional flight. The flight was conducted under 14 Code of Federal Regulations Part 91 and was operating in visual meteorological conditions. No flight plan was on file. The pilot reported no injuries and the co-pilot sustained minor injuries. The local flight originated from the Griffith-Merrillville Airport, near Griffith, Indiana, about 1700.

The pilot's accident report, in part, stated:

I was acting as a more experienced safety pilot for a certified

helicopter pilot that was conducting a refresher flight after being

recently reassigned to the Sheriff's department Aviation Division.

After approximately a half hour of flight operations in the form of

hover work, pedal turns, normal take off in the traffic pattern and return

to normal approach to landing, I requested and received positive

control of the aircraft from the less experienced pilot and was flying

and controlling the aircraft from the co-pilot seat with the dual

controls that were installed. I have flown this particular aircraft from

the co-pilot side on previous flights so this presented no unknown

challenges. The aircraft had recently been re-configured in that,

floats (permanent, not pop out) had been installed after they had been

removed approximately 5 years earlier. I have previously flown this

aircraft in this float equipped configuration so this presented no

unknown challenges to during this flight. Since the [floats] had been

recently installed and since it had been some time since they were

attached to the aircraft, I felt that it was necessary to conduct

emergency procedure training for myself in the form of a practice

autorotation to refresh my experience in this aircraft configuration. ...

The aircraft was configured for the practice autorotation in that the

aircraft was at 1200 MSL [mean sea level] or approximately 500 feet

AGL [above ground level] and the airspeed was indicating 75 mph.

The heading was approximately SW or 230 degrees. I have practiced

hundreds of autorotations from this initial configuration and in the

same geographical location, to the point that the point of intended

touchdown was the same as nearly all other practice autorotations.

Upon determining the point of entry or the practice autorotation, I

flew to that point and started the maneuver. Immediately upon

reducing the throttle and lowering the collective, the engine of the

helicopter stopped. This was confirmed by the indication of the

"split" needles and engine RPM indicating zero RPM. This was

further confirmed by the manifold pressure gauge which was rising

to atmospheric pressure. This practice autorotation had turned into

a real total loss of engine power autorotation to touchdown. I

monitored the rotor RPM and established best autorotation airspeed

at 60 mph to maintain the autorotation decent. Upon nearing the

ground at a height of approximately 30-50 feet, I flared the

helicopter to slow the forward airspeed. I then leveled the aircraft

and pulled up on the collective, using the stored energy in the rotor

system to help control the vertical airspeed from a height of

approximately 5-6 feet. The aircraft came to rest in an upright

position and both pilot occupants remained inside and were not

ejected. The main rotor blade flex downward and came in contact

with the tail boom section causing the tail rotor to separate.

Federal Aviation Administration inspectors examined the wreckage. No pre-impact anomalies were detected. The engine, a Lycoming HIO-360-D1A, serial number L-25796-51A, was operational during a subsequent test run.

At 1745, the recorded Lansing Municipal Airport, near Lansing, Illinois, weather was: Wind 220 degrees at 13 knots gusting to 19 knots; visibility 10 statute miles; sky condition scattered 7,500 feet broken 10,000 feet; temperature 27 degrees C; dew point 11 degrees C; altimeter 29.84 inches of mercury.