# NTSB FTW97TA154: Bell TH-13T, N74HL, Capitan, NM, April 7, 1997 - Type: NTSB accident investigation - Classification: Accident · No injuries · Final report - Date: April 7, 1997, 08:15 local (13:15 UTC) - Place: Capitan, NM - Coordinates: 33.540557, -105.590354 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=33.5406&lon=-105.5904&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report May 30, 1997 - Report: Approved by Office Director - NTSB case key (mKey): 20378 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW97TA154 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/20378/pdf - Page: https://openairdocs.org/ntsb/FTW97TA154 ## Probable cause loss of engine power for undetermined reason(s). ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power, maneuvering - reason for occurrence undetermined (cause) - Forced landing, emergency descent/landing - autorotation - performed - In flight collision with terrain/water, emergency landing ## Analysis The pilot reported that while flying at an altitude of about 35 feet AGL and 30 knots, 'a slight shudder was felt in the helicopter as though a change of wind direction had occurred.' All instruments and systems 'remained in the green and functioning.' Several minutes later, a complete loss of engine power occurred. The pilot recalled hearing a 'strange noise' immediately preceding the loss of power. Subsequently, he initiated a low altitude auto rotation. Approximately 10 feet AGL, the helicopter began to turn to the left, and 'in order to avoid a roll over,' the pilot lowered the collective and informed the passenger of an immanent hard landing. During contact with the ground, the main rotor contacted and severed the tail boom. Immediately following the hard landing, a fire started in the engine compartment. Both the pilot and passenger evacuated, and the helicopter was consumed by fire. Examination of the wreckage to discover the cause of the loss of engine power was unsuccessful due to extreme fire damage to the engine, fuel system, and accessories. The ambient temperature and dew point were conducive to carburetor icing. ## Factual narrative On April 7, 1997, approximately 0815 central daylight time, a Bell TH-13T helicopter, N74HL, owned and operated by the pilot, was destroyed following a loss of power and subsequent forced landing near Capitan, New Mexico. Both occupants, the commercial pilot and one passenger, were not injured. Visual meteorological conditions prevailed for the Title 14 CFR Part 91 predator control flight. A flight plan was not filed. The helicopter was airborne for approximately 45 minutes prior to the accident. The pilot reported that while flying at an altitude of about 35 feet AGL and 30 knots, "a slight shudder was felt in the aircraft as though a change of wind direction had occurred." All instruments and systems "remained in the green and functioning." Several minutes later, a complete engine failure occurred. The pilot recalled hearing a "strange noise" immediately preceding the loss of power. Subsequently, he initiated a low altitude auto rotation. Approximately 10 feet AGL, the aircraft began to turn to the left, and "in order to avoid a roll over", the pilot lowered the collective and informed the passenger of an immanent hard landing. Upon contact with the ground, the main rotor contacted and severed the tail boom. Immediately following the hard landing, a fire started in the engine compartment. Both the pilot and passenger evacuated and the aircraft was consumed by fire. Examination of the wreckage to discover the cause of the loss of engine power was unsuccessful due to extreme fire damage to the engine, fuel system, and accessories. However, according to the helicopter manufacturer, who assisted in the examination, the post impact fire most likely resulted from the right, external mounted, fuel tank breaking loose from its mounts and dislodging the fuel lines. This allowed fuel to spill onto the hot engine exhaust manifold. The helicopter was not equipped with fiberglass fuel tank straps or self sealing "break away" fuel line fittings. According to carburetor icing probability charts, the ambient temperature and dew point were conducive to carburetor icing. ## Aircraft - Registration: N74HL (not matched to a registry record) - Reported make and model: Bell TH-13T - Category: Helicopter - Serial number: 3652 - Airframe hours: 5558 - Engines: Lycoming TV0-435-B1A 291 horsepower reciprocating - Damage: Destroyed - Fire: On-Ground - Flight: Public aircraft, Part 91 - Operator: U.S Department Of Agriculture - Registered owner: Desert Eagle Helicopters Inc. - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, April 2, 1997, 2 hours before - Departed: NONE ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 37; private, commercial; airplane ratings: single-engine land; medical: class 2, valid medical--no waivers/lim.; seat: left; flight hours: 1,821 total, 372 in this make and model, 1,793 as pilot in command, 76 in the last 90 days, 41 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 45 °F, dew point 43 °F - Altimeter: 30.00 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 19970407005249A](https://openairdocs.org/incident/19970407005249A), Apr 7, 1997: Bell TH13T, Capitan, NM, Destroyed. Predator control flight. Lost power too low autorotation. Hard impact. Rotor chopped tail. Tank broke. Fuel fire. (-23) on April 7, 1997, at approximately 0815… 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.