Butler, PA, USA
N688G
WALTER S JOHNSON III AR-1
The pilot said the traffic pattern was busy, so he began the pre-rotation process as he taxied the gyroplane onto the runway to depart. At that time, the rotor disk rpm was at 140 rpm, which was 20 rpm above the recommended takeoff speed. The pilot said he slowly applied power because he had a passenger onboard, which may have allowed time for the disk speed to decay and become susceptible to blade flap. During the takeoff roll, the gyroplane’s main rotor blades struck and severed the tail assembly, resulting in substantial damage. The pilot said there were no preimpact mechanical malfunctions or failures that would have precluded normal operation.
The pilot’s failure to monitor rotor disk speed on takeoff, which resulted in blade flapping and the main rotor blades striking the gyroplane’s tail assembly.
Source: NTSB Aviation Accident Database
Aviation Accidents App
In-Depth Access to Aviation Accident Reports
