14 CFR Part 91: General Aviation
Accident occurred Friday, August 24, 2012 in Abingdon, VA
Probable Cause Approval Date: 05/08/2014
Aircraft: BELL 407, registration: N407N
Injuries: 1 Fatal.
NTSB investigators either traveled in support of this investigation or conducted a significant amount of investigative work without any travel, and used data obtained from various sources to prepare this aircraft accident report.
The pilot was transporting passengers across a lake and home from a race track at night. A witness who was boating on the lake across from the helicopter landing area watched the helicopter approach and land. He stated that the landing light was on during the landing. He watched the passengers exit the helicopter and then the helicopter lift off and turn toward the lake, descend down an embankment, and turn over the lake. The witness stated that the landing light was not on during the departure. The helicopter traveled about 150 yards when the bottom skids began to make the water spray. The helicopter then nosed over and impacted the water. The witness then directed his boat toward the impact area where he found the tail boom separated from the fuselage and the cockpit area submerged.
Examination of the fuselage, including the top Plexiglas window and frame, revealed evidence of main rotor contact. The helicopter’s engine was torn from the fuselage and could not be located due to poor visibility in the water and its irregular bottom features. The engine control unit (ECU) was retrieved, and all of the data revealed that no engine operating exceedances occurred before impact, and no accumulated engine faults were recorded during the previous engine run. The ECU data and physical evidence are consistent with power being supplied to the main rotor at the moment of impact.
Security camera video footage revealed that the pilot had successfully conducted this low-level, rapid acceleration takeoff profile several times during the day when visual spatial references were plentiful. The available data and evidence, as well as the previous flights, are consistent with controlled flight into water while conducting a rapidly accelerating, low-altitude flight after takeoff over an unlit body of water in dark night conditions. The pilot’s decision to attempt a such a takeoff at night without the aid of ambient light or the use of helicopter lights denied him the visual spatial references needed to assure safe terrain and obstacle avoidance. Additionally, the conditions during the flight were conducive to a type of pilot spatial disorientation known as “somatogravic illusion,” in which aircraft acceleration may be misinterpreted by the pilot as an increasing nose-up pitch attitude and result in inappropriate nose-down control inputs.
The National Transportation Safety Board determines the probable cause(s) of this accident to be:
The pilot’s improper decision to make a low-level departure over water in dark night conditions without lights, which resulted in controlled flight into the water. Contributing to the accident was the pilot’s likely spatial disorientation due to a vestibular illusion caused by the rapid acceleration during takeoff.
HISTORY OF FLIGHT
On August 24, 2012, about 2230 eastern daylight time, a Bell 407 helicopter, N407N, collided into South Holston Lake during a night departure from a river bank in Abingdon, Virginia. The airline transport pilot was fatally injured. The helicopter was substantially damaged when it impacted the water. The helicopter was registered to and operated by K-VA-T&W-L Aviation LLC under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. Visual night meteorological conditions prevailed, and no flight plan was filed. The flight was originating from a private field at the time of the accident.
According to a witness, while boating on the lake across from the helicopter landing zone, he watched as the helicopter came in and landed. He recalled that the landing light was on, and he watched as the passengers exited the helicopter. The helicopter then lifted and turned toward the lake, descended down an embankment and made a turn over the lake. The witness said that he noticed that the landing light was not on during the departure flight. The helicopter traveled approximately 150 yards when the bottom skids began to make the water spray on the side of the helicopter. The helicopter then nosed over and made a loud splash. The witness waited for a short moment and then turned on his spot light and moved towards the position of the helicopter. As he moved towards the helicopter, his boat bumped into the tail boom, which was floating away from the fuselage. He continued towards the helicopter and came upon the helicopter floating upside down with the skids upright approximately 2 feet above the water. The witness shined his light throughout the cabin and cockpit but did not see anyone.
PERSONNEL INFORMATION
The pilot, age 64, held an airline transport pilot certificate for airplane single-engine land, multi-engine land, and rotorcraft-helicopter issued May 27, 2008, and a second-class airman medical certificate issued February 17, 2012, with limitations for corrective lenses. The pilot's logbook was not recovered for review. According to the Federal Aviation Administration (FAA) records, the pilot reported 26,000 flight hours on his last medical.
A review of the pilot's flight schedule for that day revealed that the pilot started the passenger flights at 1500 on the day of the accident. A review of the flight schedule times revealed that 10 passenger flights between Bristol Speedway to a private residence near South Holston Lake were made in a period of 1 hour and 20 minutes. After the pilot returned, he was informed that the next flight would start at 2100. During the flights, the pilot hot fueled at the landing site adjacent to the residence where he dropped off and picked up passengers. There is no record of the amount of fuel taken onboard the helicopter during the day. According to the wife of the pilot, he was well rested the night before and there was nothing abnormal about the day. She went on to say that the pilot was in good health.
AIRCRAFT INFORMATION
The seven-seat, skid equipped helicopter, serial number 53077, was manufactured in 1996. It was powered by a Rolls-Royce model 250-C47B turbo-shaft 650-hp engine.
Review of copies of maintenance logbook records showed an annual inspection was completed March 20, 2012, at a recorded airframe total time of 2,339.1 hours, and an engine time of 2,091.0 hours. The Hobbs hour-meter showed 2,427.8 hours at the accident site. The engine control unit recorded an engine total time of 2,771.06.
Video footage from a security camera captured several daytime departures by the pilot earlier that day. In all the takeoffs, the helicopter was low enough to the surface of the lake to allow the main rotor to create a wake on the surface of the water. On the night of the accident, video footage showed the helicopter's anti-collision lights reflecting off of the lake's surface prior to the accident.
AERODROME INFORMATION
The intended landing site was in the backyard at the private residence of the owner of the helicopter, which is an area of turf grass. The landing site was elevated approximately 30 feet above the lake surface. The area is unlit and not a dedicated helipad and it was used frequently by the owner for helicopter operations.
METEOROLOGICAL INFORMATION
A review of recorded data from the Virginia Highlands Airport, Abingdon, Virginia (VJI) automated weather observation station, elevation 2,087 feet, revealed that at 2235, conditions were wind 100 degrees at 4 knots, visibility of 10 miles, cloud conditions scattered at 11,000 feet above ground level (agl).
On the day of the accident, official sunset was at 2007, end of civil twilight was at 2033, moonset was at 1917 with an elevation more than 29 degrees below the horizon, and moonrise would be 1519 on August 25, 2012. Moon phase was a waxing crescent with 51% of visible disk illuminated. The evening trip took place under nighttime VFR conditions.
WRECKAGE AND IMPACT INFORMATION
The fuselage of the helicopter was recovered on August 28, 2012, approximately 100 yards from the estimated location of the helicopter's original impact point on the water. The helicopter's engine was torn from the fuselage and could not be located due to poor visibility in the water and the irregular bottom features which rendered the search ineffective.
Examination of the cockpit area of the fuselage revealed that it had been breached during impact. The pilot and copilot's seat pans were broken away from their respective bases and deformed. The instrument panel was dislodged from its mount and held to the fuselage by wiring. A cursory examination of the instrument panel revealed that the landing light switch was found in the "both" position but the landing light circuit breaker was observed in the "out" position (turned off). Examination of the fuselage exhibited evidence of main rotor contact. The top Plexiglas window and frame exhibited evidence of main rotor contact.
Examination of the flight controls revealed that all controls from the collective and cyclic to the vertical control tubes to the hydraulic actuators to the swash plate were intact and no notable damage was observed. The forward vertical firewall exhibited rotational witness marks from the engine to transmission shaft. Rotational witness marks were also present on the transmission shaft. The forward end of the transmission shaft remained attached to the main transmission; the K-Flex coupling on the aft end of the transmission shaft had failed in overload and was splayed outward. The main rotor mast had fractured in overload at its base but had not separated. Examination of the main transmission chip detector upper and lower was found clean of debris. The hydraulic reservoir was found full of hydraulic fluid and clean of debris.
Examination of the main rotor blades revealed that all four rotor blades were fractured consistent with a sudden stoppage. The blue, red, and green pitch change links were bent; the orange pitch change link was fractured in overload. All pitch link hardware was present, and all cotter keys were installed.
The tail boom was fractured at the aft bulkhead and the fracture surfaces were consistent with a main rotor strike. Strike marks were present on both of the top of the vertical stabilizers above the tail boom and the bottom of the vertical stabilizers below the tail boom. The foreword-most 4 feet of the tail boom was not recovered. The vertical fin was not damaged, and the anti-collision light remained intact. The tail boom drive shaft was fractured at the number 3 coupling. Examination of the 90-degree gearbox revealed that the chip detector was found clean and free of debris. The 90-degree gearbox rotated with no binding or grinding. Control continuity was confirmed from the forward fracture to the tail rotor control lever upper end. The tail rotor control lever attachment point showed signs of impact damage and remnants of the arm bearing were located in the lower end of the tail cone. No anomalies were found with the tail rotor which would have prevented normal operation and control.
The engine bay showed evidence of contact by the main rotor. The mounts, engine controls, fuel, oil and electrical connections were all severed from the helicopter. The only engine components present were the Engine Control Unit (ECU), part of a throttle control arm, and a small fragment of the starter/generator mount. All engine mounts were fractured in overload and deformed. The engine oil reservoir, oil cooler, and fan were missing.
Due to extensive impact damage, control continuity could not be established from the cockpit to the engine bay. The collective was fractured at its base. The throttle twist grip was deformed and not movable by hand. The throttle was found in the full-open (fly) position. A piece of the throttle engine's throttle arm was present in the engine bay, still attached to a deformed section of throttle control linkage. The airframe-mounted fuel filter was present. The outlet fuel line to the engine had been severed, allowing water contamination of the filter bowl. The filter bowl was opened and examined. A small amount of silt was present, from the river bed but the filter was otherwise normal. The ECU baseplate was deformed due to impact damage.
MEDICAL AND PATHOLOGICAL INFORMATION
An autopsy was performed on the pilot on August 28, 2012, by the Department of Health, Office of the Chief Medical Examiner, Roanoke, Virginia, as authorized by the medical examiner for Washington County.
The FAA's Civil Aerospace Medical Institute performed forensic toxicology on specimens from the pilot with negative results for drugs and alcohol.
TEST AND RESEARCH
Examination of the recorded ECU data revealed that there were no engine operating exceedance prior to impact, and no accumulated engine faults were recorded during the previous engine run. No Incident recorder (IR) data had been written to file; however, a partial Snapshot trigger dataset had been recorded. The Snapshot trigger was caused by an Engine Torque Exceedance of 116%. Only seven sequential engine parameters were recorded in the Snapshot data. This is consistent with destruction of the helicopter occurring almost immediately after the initial over-torque event occurred. Electrical power was lost to the ECU before a full line of Snapshot data could be written or any IR data could be recorded.
Due to the limited amount of data recorded on the ECU, very little analysis of engine performance could be achieved. The disparity between main rotor rpm (Nr) and power turbine speed (Np) is attributable to the rapid deceleration of the main rotor as it impacted the water. There is a 24 millisecond cycle time for the data write; however, the Nr signal first passes through a digital converter before the Np signal. During a rapid deceleration of the main rotor, the recorded value for Np will be lower than that recorded for Nr. The recorded Nr data was sampled a few milliseconds before the recorded Np data. The Np data was recorded during or immediately following the main rotor strike of the water.
ADDITIONAL INFORMATION
Spatial Disorientation
According to Spatial Disorientation in Aviation (F.H. Previc and W.R. Ercoline), the otoliths (tiny organs of the inner ear), sense the acceleration of gravity and the acceleration associated with translational motions. Because the otoliths cannot distinguish between these two types of acceleration, they can only sense a combination of these two forces, the gravitoinertial force (GIF) vector. During coordinated, unaccelerated flight, the GIF vector is directed straight down through the pilot's seat. When an aircraft accelerates rapidly, however, the GIF vector is displaced aft, causing a false sensation of pitching up. This misperception, known as the somatogravic illusion, is normally dispelled when the pilot views the external horizon and/or the flight instruments. If no external horizon is visible and the flight instruments are not continuously monitored or are not correctly interpreted, the somatogravic illusion can persist, leading to an inaccurate understanding of aircraft orientation and direction of motion known as spatial disorientation, a condition that can lead to inappropriate pilot control inputs.
Spatial disorientation illusions are described extensively in FAA pilot training literature. For example, the 2012 Aeronautical Information Manual states, "A rapid acceleration during takeoff can create the illusion of being in a nose up attitude." Similarly, the FAA Instrument Flying Handbook states, "A rapid acceleration, such as experienced during takeoff, stimulates the otolith organs in the same way as tilting the head backwards. This action creates the somatogravic illusion of being in a nose-up attitude, especially in situations without good visual references." The Manual and the Handbook warn that, "The disoriented pilot may push the aircraft into a nose-low or dive attitude." Identical information is included in the FAA's Pilot Handbook of Aeronautical Knowledge. This particular illusion is so well recognized that information about it is included in the FAA's private pilot, instrument rating, and airline transport pilot knowledge test guides and the FAA practical test standards for private pilots.
According to FAA Advisory Circular AC 60-4A, "Pilot's Spatial Disorientation," tests conducted with qualified instrument pilots indicated that it can take as long as 35 seconds to establish full control by instruments after a loss of visual reference of the earth's surface. AC 60-4A further states that surface references and the natural horizon may become obscured even though visibility may be above VFR minimums, and that an inability to perceive the natural horizon or surface references is common during flights over water, at night, in sparsely populated areas, and in low-visibility conditions.
NTSB Identification: ERA12FA527
14 CFR Part 91: General Aviation
Accident occurred Friday, August 24, 2012 in Abingdon, VA
Aircraft: BELL 407, registration: N407N
Injuries: 1 Fatal.
This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when the final report has been completed.
On August 24, 2012, about 2230 eastern daylight time, a Bell 407, N407N, crashed into South Holston Lake during a night departure from a river bank in Abingdon, Virginia. The airline transport pilot was fatally injured. The helicopter was substantially damaged when it impacted the water. The helicopter was registered to and operated by K-VA-T&W-L Aviation LLC under the provisions of 14 Code of Federal Regulations Part 91, as a personal flight. Visual night meteorological conditions prevailed and no flight plan was filed. The flight was originating at the time of the accident.
According to a witness in a boat, he watched the helicopter land with the landing light on and the passengers exit the helicopter. The helicopter then departed without the landing light on and turned toward the lake, descended down an embankment, and made a turn over the lake. The helicopter traveled approximately 150 yards when the bottom skids collided with the lake. The helicopter nosed over and made a loud splash. The witness waited for a short moment and then turned on his spot light and moved towards the position of the helicopter. As he moved forward, his boat collided with the tail boom which was floating away from the fuselage. He continued forward and the cabin area was floating upside down.
The helicopter was recovered from the lake and is pending further examination by the NTSB.
IDENTIFICATION
Regis#: 407N Make/Model: B407 Description: Bell 407
Date: 08/25/2012 Time: 0220
Event Type: Accident Highest Injury: Fatal Mid Air: N Missing: N
Damage: Substantial
LOCATION
City: ABINGDON State: VA Country: US
DESCRIPTION
N407N BELL 407 ROTORCRAFT CRASHED INTO A LAKE, THE 1 PERSON ON BOARD IS
MISSING AND PRESUMED FATAL, NEAR ABINGDON, VA
INJURY DATA Total Fatal: 1
# Crew: 1 Fat: 1 Ser: 0 Min: 0 Unk: 0
# Pass: 0 Fat: 0 Ser: 0 Min: 0 Unk:
# Grnd: Fat: 0 Ser: 0 Min: 0 Unk:
OTHER DATA
Activity: Unknown Phase: Unknown Operation: OTHER
FAA FSDO: RICHMOND, VA (EA21) Entry date: 08/27/2012
Flags fly at half-mast at Virginia Highlands Airport in Abingdon, Virginia
~
A barge pushes a recovery crane near the site of a helicopter crash on South Holston Lake Saturday evening. Crews are still searching the site of a Friday night helicopter crash believed to have involved Food City chief pilot Bill Starnes, but the crane was sent back to a nearby marina until Sunday.
By David Crigger/Bristol Herald Courier
A police boat keeps boaters away from the area of Friday nights corporate helicopter crash on South Holston Lake. The helicopter belonged to Food City and was leaving the home of CEO and President Steve Smith when it went into the lake.
Spectators gathered on the shoreline early this morning as rescue crews continued the search for a helicopter pilot who crashed into the lake late Friday.
Rescue crews assist divers in the search for a missing helicopter pilot this morning. The aircraft crashed into South Holston Lake late Friday.
Photo by AP Photo/Jason Smith, CIA Bristol Motor Speedway, Pool
A Food City corporate helicopter crashed into a South Holston Lake in upper East Tennessee after leaving Bristol Motor Speedway following the Nationalwide race late Friday, August 24, 2012. The race is sponsored by the grocery chain. The search continued early Saturday, Aug. 25, 2012 for the pilot of the craft, who authorities believe was the lone occupant.
http://www2.tricities.com
Keep checking Tricities.com for more information. On Twitter, follow @BHC_Allie and@tricities_com as reporter Allie Robinson posts updates throughout the day.
Emergency 911 calls on the downed helicopter
Calls on the helicopter traffic begin about a third of the way into the audio. Go to about 11 minutes in to catch the start. Live Scanner Audio Credit: http://Scannerfood.com and hosted by http://RadioReference.com
UPDATE: 9 p.m. SATURDAY
Jerry Caldwell, general manager at Bristol Motor Speedway, made the following announcement over the Speedway public-address system regarding the accident prior to the start of the race: “As you may have heard, our partners at Food City need our prayers. They are like family to us. When they hurt, we hurt. So please keep them in your thoughts and prayers. Thank you.”
UPDATE: 7 p.m. SATURDAY
The Sullivan County, Tenn., Sheriff’s Office dive team joined the search Saturday for a missing corporate pilot whose helicopter crashed lated Friday in South Holston Lake.
Search crews who had spend the night searching the wreckage, spent much of Saturday using side-sonar in their efforts.
The divers will continue their work through the night Saturday as well, and until the pilot is found, Corinne N. Geller, a public relations officer with the Virginia State Police, said in a written news statement updating the search.
Geller confirmed Saturday that the helicopter did break apart upon impact with the water, with the bulk of the aircraft still submerged.
The depths of the water at the crash site ranges from about 25 to 40 feet.
UPDATE: 12:15 p.m. SATURDAY:
Dive crews are still searching the wreckage this afternoon for the pilot of the crashed helicopter, said Virginia State Police Sgt. Michael Conroy.
The crews will "keep searching until they find" him, Conroy said. Police still haven't named the pilot missing from Friday night's wreck.
------------------------------
UPDATE 11:32 A.M. SATURDAY:
Castlewood, Va., resident Larry Buchanan was sitting around a campfire with his friends and family late Friday, watching as helicopters flew in and over the area at Washington County Park on South Holston Lake.
They were watching the helicopter that crashed take off again after its second visited to the area, Buchanan said.
The helicopter had just taken off from the house when it crashed, he said.
“It smacked the water and sounded like a big wall falling and then there was silence," Buchanan said. "We came running down here, but there was nothing we could do from the shore.”
He said boats that were already out on the lake rushed over to the site.
The helicopter was flying low over the lake, he said, but that was normal from what they had seen; the aircraft would stay low until it cleared the trees, he said.
Police and rescue squads were on the scene pretty quick after the crash, he said.
--------------------------------------
UPDATE 10:45 A.M. SATURDAY:
Additional divers and sonar equipment arrived at South Holston Lake this morning to aid in the search for the pilot of a Food City helicopter that crashed into the water near Washington County Park late Friday.
The helicopter has been located, but rescue teams working through the night were still unable to find the pilot, who was the only person on board when the helicopter crashed, Virginia State Police Sgt. Michael Conroy said.
“Right now we’re searching around the crash scene,” Conroy said.
The crash occurred about 10:30 p.m., shortly after the end of the Food City 250 race at Bristol Motor Speedway. The pilot is the only person believed to have been on board; authorities have declined at this point to release the pilot’s name.
“Last night when they first got on scene, it [the helicopter] was skids up,” Conroy said. “That may have changed with the current and everything. It did break up into pieces; we’re not sure how many pieces. It’s still submerged in probably 20 to 25 feet of water.”
The helicopter, according to the Federal Aviation Administration registry, was registered to K-VA-T and W-L Aviation LLC in Abingdon, Va. It was a Bell model 407, manufactured in 1996.
“Right now, we’re focusing on recovering the pilot,” Conroy said this morning. “After that we’ll move the helicopter for inspection. That’s down the road.”
----------------------------------------------
Virginia State Police divers and troopers continue this morning to for the pilot of a Food City helicopter that crashed into South Holston Lake late Friday.
Divers spent much of the night searching the wreckage for the pilot, said Corinne Geller, state police spokesperson, in a written statement sent out this morning.
The police search and recovery team will use side-scan sonar today to help look for the pilot. The helicopter remains in the water upside down, she said. Police will work to remove the wreckage today, she said.
The corperate Bell helicopter had been bringing passengers from Bristol Motor Speedway to a private residence along Lake Road, Geller said. One of the passengers had just been dropped off when the crash occurred, she said.
Keep checking back to Tricities.com for more information. On Twitter, follow @BHC_Allie and@tricities_com as reporter Allie Robinson posts updates throughout the day.
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3:03 a.m.:
Divers continued searching early this morning for the pilot of a helicopter that crashed into South Holston Lake late Friday.
The pilot was the only person on board the Bell
helicopter, owned by K-VA-T Food Stores, the parent company for the Food
City grocery chain, Virginia State Police Sgt. Michael Conroy said.
The helicopter crashed into the lake about 10:30
p.m. Friday, Conroy said, near Lake Road and County Park Road just north
of the Tennessee border.
As of 2 a.m. the pilot still had not been found, and police and rescue crews plan to search until he is located, Conroy said.
“Right now the focus is on finding the pilot,” he said just before 2 a.m.
State police dive crews and a state police
helicopter could be seen around the site of the crash early Saturday.
The helicopter’s spotlight swept the lake as the dive teams methodically
checked the area between Painters Creek Marina and Washington County
Park. The water in some places near the crash site is at least 40 feet
deep.
The helicopter was found, and is still in the lake, Conroy said.
The Federal Aviation Administration is expected to
be on the scene this morning and will investigate the cause of the
crash, Conroy said.
Food City is the corporate sponsor of the Food City
250 Nationwide Series race at Bristol Motor Speedway. The crash occurred
less than an hour after the race concluded Friday.
The Washington County Sheriff’s Office, conservation
officers with the Virginia Department of Game and Inland Fisheries and
the Green Springs Volunteer Fire Department responded to assist with the
search, Conroy said. ------------------------------------------------------------------------------
12:30 a.m.:
A Bell helicopter registered to Food City’s parent company and an Abingdon, Va., aviation company crashed late Friday into South Holston Lake, near the Washington County Park on County Park Road, which is just north of the state line.
Washington County Sheriff Fred Newman confirmed that
the aircraft had gone down just before 11 p.m., landing in the water,
and that search and rescue teams from his office and several other
agencies were searching for survivors. The search was expected to last
well into the morning.
Food City President and CEO Steven C. Smith was not
on board when the helicopter went down, but the crash occurred not far
from his home on South Holston Lake.
It is unclear at this time how many passengers were
on board the helicopter at the time of the crash, which happened less
than an hour after the end of the Food City 250 at Bristol Motor
Speedway.
Food City has sponsored that NASCAR Nationwide Series race for 20 years.
The emergency agencies assisting in the search late
Friday include the Virginia State Police, the Washington County
Lifesaving Crew and the Green Springs Volunteer Fire Department. The
state police medical helicopter was providing support with spotlights on
the water.
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