N30TV

HISTORY OF FLIGHT

On February 3, 1998, about 0850 central standard time, a Bell UH-1H helicopter, N30TV, operated by the Tennessee Valley Authority (TVA), as a Title 14 CFR Part 91 public-use flight, impacted with a pole near Savannah, Tennessee. Visual meteorological conditions prevailed, and no flight plan was filed. The helicopter was destroyed. Two airline transport pilots, one crewmember observer, and one TVA employee working on the pole, were fatally injured. One observer (a helicopter crewmember) received minor injuries. The flight had originated from Muscle Shoals, Alabama, at 0630, en route to Savannah. The flight was conducted to support a rope stringing and wire installation operation which was being conducted by the TVA.

The helicopter departed from the TVA Air Service hangar with a crew of two, TVA's Chief Pilot and an observer. Two additional crew members, another observer, and a contract pilot, had driven to Savannah earlier and were to meet the helicopter in Savannah. After a 30 minute flight, the helicopter landed at the TVA line maintenance facility, and the crew attended a line installation briefing. The two other crew members were there and they also attended the briefing. The briefing lasted about 30 minutes, and the flight departed at 0730.

The helicopter flew about 1.2 hours stringing ropes/wires before it proceeded to the area where the accident occurred. Ground witnesses observed the helicopter approach a pole with a workman at the top, at a height of about 150 feet above the ground. The workman's task was to attach a conductor pull rope to the end of a 17-foot sling and 600 pound weights, with a shackle assembly, which were suspended from the bottom of the helicopter. Ground witnesses saw the helicopter approach the workman and the pole with the nose of the helicopter heading in a northwest direction. The helicopter came to a high hover over the pole, and the workman attempted to attach the rope. The witnesses said the helicopter began to get lower and lower until the workman could no longer reach the line coming from the helicopter. As the helicopter descended it drifted left and forward of the pole and the workman. The ground witnesses said the helicopter started to back up and climb when the main rotor blades struck the pole and the workman. The helicopter then rolled to the right, descended and impacted the ground on its right side.

The Foreman in charge of the ground operation, who was located close to the pole, identified as STR 51, at the time of the accident, said that before the mission started he talked to the workman that was to climb the pole, to make sure "he was comfortable " with hooking the ropes up. The Foreman was told by the workman, "he had done it before, he wasn't concerned." The Foreman said, "...I had my truck parked right next to STR 51 where I could see everything." He said he talked to the pilot-in-command [PIC], "whom [he] thought was flying the helicopter."

The Foreman said that the first rope that had been strung, had been picked up from a nearby field, and it was then brought to his attention that they might have "trouble" flying the next phase, the bottom, without getting "it bucked." It was decided to "...let [the workman] take [the] rope to the top of the pole to hook to the helicopter." The Foreman said he "discussed it" with the PIC and he replied, "Okay." The workman was at the top of the pole when the helicopter came to a hover over him so that he could hook the rope to the helicopter. The Foreman said, "...from where I was standing it looked like he [the workman] was having a hard time getting the rope hooked. I was still standing between the pole and my truck pacing around. I thought I saw [the workman] just stop and start hugging the pole, because the wind from the helicopter was so strong. I saw men in the helicopter leaning out, (spotters) watching what was going on. For some reason I thought they could see what was going on and they were just going to leave. When I looked back up I saw the 600 lbs. weight...bouncing off [the workman's] back and I knew something was wrong for sure." The Forman then ran to his truck and, "...got on the radio to tell [the PIC] he was too close to my man, that he needed to leave so we could regroup. No sooner than I finished I heard a noise, when I looked up the helicopter had hit the top of the pole with their main rotor...."

According to the TVA Aviation Operation Manual, under the heading External Load Operation, the last paragraph on page 26 states: "...external load operations shall not be conducted unless there are two-way radio communications between the pilot and ground crew unless otherwise authorized by the Manger of Aviation Services. Hand or light signals will not be employed except when initially hooking up or releasing load. In case of radio failure, the pilot in command shall terminate operation until the transceiver is repaired or replaced...." During this operation the Foreman said his radio was in his truck, some distance from where he was positioned. There was no evidence found, that from the time the helicopter arrived at the pole, until the accident had occurred, that there was not any radio communication between the ground and the pilot. In addition, examination of the helicopter's radios did not indicate any discrepancies.

The surviving crew member, who was in the helicopter at the time of the accident, confirmed that their mission that day was to pull rope across the Tennessee River. He said that the helicopter approached the pole centerline, from above the pole. Commands were given by the other observer, located on the right side of the helicopter, to the pilot in the right front seat of the helicopter, who was on the controls. The pilot was told by the right side observer, "...to ease the aircraft down and hold position, along with move left and move right commands. These commands were made to move [the] aircraft wire pulling rigging system even with the top of the pole where a linemen from the ground would be located to connect the rope." He further stated that the workman on the pole, "was unscrewing a pin through a swivel in order to insert [the] loop of the rope and reinstall [the] pin." The weights on the rigging "had settled" on the side of the pole with the helicopter, "drifting just past the pole." "A command was given to ease back to bring the rigging back vertical and [the] weights off the pole." The left side observer said he looked away when, "the linemen lost the swivel." When he looked back down, the helicopter had, "drifted to the left and forward of the pole." The workman and the pole were no longer visible to him from his location in the helicopter.

The surviving crew member described the following events, "...the pilot asked what he needed to do and a command was given to back off and try again...immediately followed with move left command and repeated in about two seconds. Another two seconds past and [the right side observer] yelled left, left, left, left. Immediately following the command I felt and heard both main rotor blades strike the pole. This caused the aircraft to turn 90 degrees to the left and roll hard right."

In addition, after impact the engine was still running. The surviving crew member said, "he moved behind the co-pilot's seat to look for the fuel boost pump cut off switch. The control was not visible...I placed the battery switch in the off position...grabbed the co-pilot's collective control to roll the throttle to flight idle, but it was jammed...I disconnected the battery as I ran around to the opposite side of the aircraft...I moved to where the engine was located and tried to manually move [the] throttle linkage to [the] cut off position, but it was jammed. I went to climb back in the cabin to locate the fuel shut off valve, but [was] told...that the power lines we landed on were hot...I told [them] to shut the power off [and this was done immediately]...I asked [a linemen] to help me back into the aircraft. Once inside I saw the panels covering the fuel valve had been torn off and immediately moved the manual lever to the off position. I then exited the aircraft...the engine shut down in a span of 20 to 30 seconds."

The accident occurred during the hours of daylight approximately 35 degrees, 03 minutes north, and 088 degrees, 02 minutes west.

PERSONNEL INFORMATION

Information on the pilot is contained in this report on page 3, under First Pilot Information. Information on the Second Pilot is contained in this report in Supplement E, Second Pilot Information. The pilot sitting in the left front seat was the pilot-in-command. He was also the Chief Pilot for the TVA. On the accident flight, the Chief Pilot was completing training for the second pilot in aerial line installation operations and procedures associated with the rope/wire stringing operation. In addition, the observer on the right side of the helicopter was to train the left side observer in aerial line installation operations and procedures associated with the rope/wire stringing operation.

METEOROLOGICAL INFORMATION

Meteorological information is contained in this report on page 3, under Weather Information. The reported winds at the Savannah Airport located about 5 miles southeast of the crash were from 110 degrees at 9 knots with gusts to 19 knots. It was determined that the helicopter approached the pole from southwest to northwest. This would have set up a wind condition on the approach to the pole from the helicopter's tail. The helicopter then pointed the nose in a westerly direction as it hovered over the pole which placed the relative wind on the left side of the helicopter toward the right of the helicopter, and toward the pole, at the same time the helicopter was hovering to the left of the pole.

MEDICAL AND PATHOLOGICAL INFORMATION

An autopsy was performed on both pilots, on Fe...