N45LW Herron LITTLE WING AUTOGYRO accident

NTSB FTW95LA031 · 1994-10-21 · LITTLE ROCK, AR · near 1M1

Summary

A HOMEBUILT GYROPLANE ROLLED INVERTED DURING LANDING ON A CONCRETE RUNWAY. THE INITIAL TOUCHDOWN WAS ON THE TWO FRONT MAIN LANDING GEAR, AND AS THE TAIL WHEEL CAME INTO CONTACT WITH THE GROUND, THE TAIL OF THE AIRCRAFT TURNED SHARPLY TO THE RIGHT. THE AIRCRAFT THEN SWERVED TO THE LEFT AND ROLLED INVERTED TO THE RIGHT CAUSING STRUCTURAL DAMAGE. EXAMINATION OF THE AIRCRAFT REVEALED A FRACTURED TAIL WHEEL ASSEMBLY MOUNTING BRACKET AND LOOSE TAIL WHEEL. THE PILOT EXPERIENCED 'TAIL WHEEL SHIMMY' DURING GROUND TAXI TESTING THE PREVIOUS DAY.

Full narrative

On October 21, 1994, at 1500 central daylight time, a Herron Little Wing Autogyro, N45LW, was substantially damaged while landing near Little Rock, Arkansas. The private pilot was not injured. Visual meteorological conditions prevailed for the local test flight.

The pilot, and builder of the gyroplane, was conducting initial low level flight and taxi tests at North Little Rock Municipal Airport. He stated that the "initial flight tests" consisted of climbs, descents, and S-turns conducted at low altitude over the runway surface. Both hovering and roll-on landings were conducted with power on. These were accomplished by taking off from the approach end of the runway, flying the length of the runway at low altitude, and landing the airplane at the departure end. This sequence was accomplished 10 or 12 times with no problems. The pilot stated that, during the last landing, he attempted to land the gyroplane with power off and 10 to 15 knots of forward airspeed. The initial touchdown was on the two front main landing gear, and as the tail wheel came in contact with the ground, the tail turned sharply to the right. The aircraft then swerved to the left and rolled inverted to the right causing structural damage.

After the accident, the pilot reported that the aircraft had a "tail wheel shimmy" during ground taxi testing the day prior to the accident. Examination of the aircraft after the accident revealed that the mounting bracket for the tail wheel assembly was fractured for undetermined reasons, and the tail wheel was loose.

Probable cause

THE FRACTURED TAIL WHEEL MOUNTING BRACKET AND LOOSE TAILWHEEL. A FACTOR WAS THE PILOT'S CONTINUED FLIGHT TESTING AFTER EXPERIENCING TAIL WHEEL SHIMMY ON THE PRIOR TEST FLIGHT. The National Transportation Safety Board determined the probable cause of this accident.

Circumstances

Event type: Accident
Highest injury: None
Weather conditions: Visual Meteorological Cond
Light condition: Day
Sky condition: BKN
Ceiling (ft): 1400
Visibility (sm): 7
Wind direction: 210
Wind speed (kt): 4
Temperature (F): 72
Nearest airport: NORTH LITTLE ROCK MUNI
Distance from field: 0.0
Airport elevation: 542

Aircraft

Registration	Make	Model	Damage	FAR part
N45LW	HERRON	LITTLE WING AUTOGYRO	SUBS	091

Sequence of events

#	Occurrence	Phase
1	130	Cruise
2	260	Cruise
3	380	Cruise

Findings

Finding
10409	cause
10408	cause
24007	factor
24539