20010105000479A

(-23) Pilot was utilizing this helicopter to distribute fertilizer via sling-loaded fiberglass bucket. Fertilizer was to be dispensed from the bottom of the bucket through a hydraulically activated mechanism. The hydraulic pump was run by the helicopter. However, the hydraulic system was solely for the bucket mechanism. The hydraulic pressure gaudge was located on the left side of the helicopter outside and behind the cockpit/cabin. Pilot initiated the flight to dispense fertilizer over a tree field. The pilot was sitting in the left seat of the helicopter and after, picking up the a/c and the full, sling-loaded, bucket to begin dispensing fertilizer, the pilot realized no fertilizer was being dispersed. Thinking it might be a hydraulics problem, the pilot landed to check the gauge. The pilot was in a remote area by himself. In order to effectively check the output of the hydraulic system, via the pressure gauge, the pilot needed to be a 100% operating RPM. In order to look at the gauge, the pilot needed to step out of the helicopter. So, while at full operating RPM, the pilot proceeded to climb out of the helicopter to check the pressure gauge. While swinging his right leg around overthe cyclic, the pilot fell out of the helicopter face first on to the ground. While falling to the ground, the pilot's left hand, situated at the back of the collective's mechanic pivot point, pushed the collective to the full position. As the pilot lay on the ground the a/c lifted up while circling right, with the bucket and it proceeded to fly unmanned for several minutes. As the helicopter was making wide circles to the right at several hundred feet, unmanned with the fertilizer bucket attached, the bucket began to oscillate. The oscillations finally increased to the point that the rotor system chopped the tailboom off and the helicopter crashed to the ground approx. 1500FEET from where it took off. (.4) on January 5, 2001, about 1500 central standard time, a Hiller UH-12E, N112EC, registered to b and s air, inc., operating as a title 14 CFR part 137 aerial application flight, crashed in the vicinity of Cleveland, Tennessee. Visual meteorological conditions prevailed and no flight plan was filed. The rotorcraft was destroyed, and the commercially-rated pilot, was not injured. The flight originated about 15 minutes before the accident. Accord ing to the pilot, he was applying fertilizer to pine trees from a hydraulically operated simplex bucket on a 25-foot external sling when the bucket stopped dispensing. He landed the rotorcraft to try and determine if the malfunction was hydraulic or mechanical. To do so, since he was the sole occupant aboard, and the ground handler was running an errand, he had to set the craft down, keep operating power on the engine, step out of the cockpit onto the skid, and read the externally mounted hydraulic pressure gage. As he exited the cockpit, he slipped and somehow during the fall, he bumped or grabbed the collective. As the unmanned rotorcraft lifted off, the left landing skid struck him in the face, and by the time he could react, the rotorcraft was at 100 feet AGL, and climbing. The craft stayed airborne for about 30 to 45 seconds while attaining an altitude of about 500 feet AGL, in a right spin before the main rotor collided with and severed the tail boom. According to an FAA inspector, the engine power had to be near 100 percent operating RPM to effectively check hydraulic pump output. As the left-seated pilot swung his right leg over the cyclic, he tripped and fell. While falling, his left hand, which was positioned aft of the collective's pivot point, somehow engaged the collective control column to the full up position. Once the rotorcraft was airborne and climbing in right circling flight, the loaded fertilizer bucket began ever-diverging oscillatory motions until it caused the main rotor to severe the tail boom and the rotorcraft crashed about 1,500 feet from its liftoff point.