# NTSB ANC95TA166: Bell 206B, N84TA, Glennallen, AK, September 10, 1995 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Final report - Date: September 10, 1995, 15:45 local (23:45 UTC) - Place: Glennallen, AK - Coordinates: 62.100814, -145.53096 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=62.1008&lon=-145.5310&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: Serious injuries - Injuries: 1 serious, 1 minor, 1 uninjured; on the ground: 1 serious - Status: Completed, report May 9, 1996 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - NTSB case key (mKey): 2751 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC95TA166 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/2751/pdf - Page: https://openairdocs.org/ntsb/ANC95TA166 ## Probable cause The pilot's improper in-flight planing/decision and inadequate supervision of the passenger, which allowed the helicopter's lateral center-of-gravity to be exceeded. Factors relating to the accident were: pressure (compelling influence) on the pilot and passenger that was induced by the need to rescue the stranded pilot from a life threatening situation, high winds, and large waves. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of control - in flight, hover - in ground effect - rescue - initiated, pilot in command - pressure induced by conditions/events, pilot in command (contributing factor) - pressure induced by conditions/events, passenger (contributing factor) - in-flight planning/decision - improper, pilot in command (cause) - supervision - inadequate, pilot in command (cause) - weather condition - high wind (contributing factor) - terrain condition - large wave/swell (contributing factor) - aircraft weight and balance - exceeded (cause) - In flight collision with terrain/water, hover - terrain condition - water,rough ## Analysis The pilot and passenger of a Bell 206B helicopter, N84TA, overheard radio transmissions about a float equipped Cessna 180A, N94259, that had become inverted on a lake. The helicopter pilot and passenger attempted a rescue of the stranded pilot, who had been sitting on the inverted floats of the airplane for about 5 hours and displayed symptoms of severe hypothermia and shock. A 30 knot wind was producing 3 to 4 feet waves. As the helicopter was hovered next to the airplane, the passenger partially stepped into an external load basket on the right side of the helicopter and began to assist the stranded pilot aboard the helicopter. At about that time, the helicopter began to roll to the right, and the main rotor blades struck the surface of the lake. The helicopter then impacted the lake and sank. The stranded pilot was struck by the helicopter's landing gear skid tube during the crash and received a serious chest injury. The pilot of a third aircraft (float equipped Beaver) observed the events and landed on the lake to rescue all of the participants. (See: ID Number ANC95LA164 for the initial accident involving the Cessna 180.) ## Factual narrative On September 10, 1995, about 1545 Alaska daylight time, a Bell 206B helicopter, N84TA, crashed while conducting a rescue operation on Tazlina Lake, about 20 miles southwest of Glennallen, Alaska. The helicopter was being operated as a visual flight rules (VFR) local area flight under Title 14 CFR Part 91 when the accident occurred. The helicopter, registered to Trans Alaska Helicopters Inc., Anchorage, Alaska, and operated by the U.S. Department of Interior, was destroyed. The certificated commercial pilot received minor injuries. A Bureau of Land Management employee, the sole passenger, was not injured. A stranded pilot, the subject of the rescue, received serious injuries. Visual meteorological conditions prevailed. The flight originated at the Gulkana airport, Gulkana, Alaska, at 1520. The operator reported that the helicopter was conducting survey operations and the pilot overheard radio transmissions about a float equipped airplane that had inverted on Tazlina Lake. A military rescue helicopter was reported to have an estimated time of arrival (ETA) at the scene of about 2 hours. The pilot and passenger volunteered to attempt a rescue of the stranded pilot who was reported to be sitting on the inverted floats of the airplane for about 5 hours. The helicopter arrived at the scene and the pilot hovered next to the airplane. The pilot of the airplane displayed symptoms of hypothermia and was unresponsive to the rescuers. The passenger of the helicopter partially stepped into an external load basket on the right side of the helicopter and attempted to assist the stranded pilot into the right side of the helicopter. This placed a lateral weight change on the right side of the helicopter. The helicopter pilot displaced the cyclic control to the left to maintain a level hover. The helicopter continued tilting to the right and the main rotor blades struck the surface of the lake. The helicopter crashed into the lake and sank. The two occupants of the helicopter escaped from the helicopter and swam to the stranded pilot who had been thrown into the water. The pilot of a float equipped airplane observed the events and elected to land on the lake. A passenger in the airplane assisted in rescuing the occupants of the helicopter and in getting the stranded pilot onto a float and eventually into the cabin of the airplane. The pilot taxied to the shore of the lake where the military rescue helicopter arrived to transport the victims. The stranded pilot reported that he was struck by the helicopter's landing gear skid tube during the crash. The pilot's physician reported that he received a bilateral pneumothorax and anterior and posterior rib trauma with flail segments consistent with a heavy crush injury. The initial accident involving the stranded airplane is ANC-95-L-A164. ## Aircraft - Registration: [N84TA](https://openairdocs.org/deregistered/N84TA-1995-11-06), registration cancelled 1995-11-06, S/N 594 (OpenAirDocs) - Reported make and model: BELL 206B - Registry model: [Bell 206B](https://openairdocs.org/model/bell-206b) (registry code 1181511) (OpenAirDocs) - Category: Helicopter - Serial number: 594 - Airframe hours: 8118 - Engines: ALLISON 250-C20 420 horsepower turbo shaft - Damage: Destroyed - Flight: Public aircraft, Part 91 - Operator: U.S. Dept. Of Interior - Registered owner: Trans-Alaska Helicopters Inc. - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, September 6, 1995, 10 hours before - Departed: GKN, AK ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 35; commercial; instrument ratings: helicopter; medical: class 2, valid medical--no waivers/lim.; seat: right; flight hours: 6,500 total, 6,000 as pilot in command, 150 in the last 90 days, 30 in the last 30 days, 5 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 180° at 30 knots - Visibility: 30 statute miles - Lowest ceiling: 5,500 ft broken - Temperature: 50 °F, dew point 45 °F - Altimeter: 29.00 inHg ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 19950910028279A](https://openairdocs.org/incident/19950910028279A), Sep 10, 1995: Bell 206B, Glennallen, AK, Destroyed. Rolled while hovering to rescue pilot from his overturned floatplane. Main rotors hit the water. Crashed and sank. From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.