29 Jul 2015: AIRBUS AS350-B2 — US DEPARTMENT OF HOMELAND SECURITY — Tucson, AZ

No fatalitiesTucson, AZ, United States

An Airbus AS350-B2 sustained substantial damage after the tail boom separated during a quick stop maneuver demonstration.

What happened

On July 29, 2015, an Airbus AS3im50-B2, registration N6095U, was involved in an accident in Tucson, Arizona. The flight instructor was demonstrating a quick stop maneuver to a student pilot. The crew had hover taxied to the approach end of the runway and established a hover between 65 and 75 feet above the ground.

To initiate the maneuver, the instructor accelerated the aircraft to 65 knots. While explaining the procedure, the instructor lowered the collective and applied aft cyclic. As the helicopter began to settle, the instructor misperceived the aircraft's altitude relative to the ground, causing the skids to impact the runway surface with significant force.

Following the initial impact, the instructor increased collective, causing the helicopter to ascend and move aft. During this movement, the tail boom separated from the aircraft and struck the left side of the fuselage. The aircraft continued to yaw left while on the ground, spinning in two complete circles on its skids before coming to a stop. The accident resulted in one minor injury and no fatalities.

The investigation

Investigators found that the tail boom and the main rotor system sustained substantial damage. The crew reported that there were no mechanical malfunctions or anomalies present in the aircraft prior to the impact that would have prevented normal operations.

Probable cause

The flight instructor's failure to correctly perceive the helicopter's altitude relative to the runway during a low-altitude maneuver, which led to the ground impact.

Contributing factors

Instructor/check pilotAltitude — Not attained/maintained