The helicopter pilot was supporting a seismic drilling operation, at a remote drill site. He had just completed moving one of the seismic drills via long line and had landed the high-skid, turbine-powered helicopter in a clear area to wait for the next move. After landing, before reducing the power to flight idle and locking the flight controls, he opened the right-side door, returned his right hand to the cyclic, and leaned out to ensure the tail rotor was clear of obstacles. While looking rearward, he inadvertently moved the cyclic to the right, and the helicopter rolled up on the right skid. He immediately applied left cyclic, but the main rotor blades struck the snow. The helicopter sustained substantial damage to the rotor system, tail boom, and fuselage. The pilot indicated there were no preaccident mechanical malfunctions or anomalies that would have precluded normal operation. In the pilot’s written statement to the National Transportation Safety Board he noted that the accident might have been avoided if he had used the collective lock before engaging in activities outside the cockpit.