DEN05LA131 · Aerospatiale SA315B
Aerospatiale SA315B · Accident: loss of control in flight while maneuvering
From Duschene, UT to Duschene, UT
Event
- NTSB case
- DEN05LA131
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 0 · all aircraft and ground
- Ground fatalities
- Unknown
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- General aviation
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
Aerospatiale SA315B
- Aircraft type
- Aerospatiale SA315
- Category
- Helicopter
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N220SH
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Duschene, UTTo Duschene, UT
- Aircraft age
- Not recorded
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 133: Rotorcraft Ext. Load
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- Maneuvering
- First occurrenceThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Loss of control in flight
- Also codedOther events the NTSB coded in the sequence, such as a wire strike after a loss of power. Flight Findings uses them for its kinds of event. Glossary
- Tree(s)
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Substantial
Cause areas
- Reason for occurrence undetermined
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
During a helicopter external load operation, the pilot was attempting to lift a 1,500 pound drill rig that was attached to the end of a 75-foot long line at a terrain elevation of approximately 7,000 feet msl. As the drill was being lifted off the ground, the helicopter "suddenly [and] violently accelerated (pitched) down [and] left." The pilot attempted to correct the uncommanded movement by applying right aft cyclic; however, the helicopter began a "rapid spin to the left." A ground witness observed the helicopter complete 3 or 4, 360-degree rotations. The pilot then closed the throttle to the flight idle position, and the left rotation stopped. The helicopter entered a descent toward the terrain with approximately 10 knots of forward airspeed. Approximately 30-40 feel above ground level (agl), the pilot pulled the "remaining" collective to slow the descent and rotor RPM. The helicopter's main rotor blades contacted trees, and subsequently the helicopter came to rest on its right side. During the accident sequence, the pilot did not jettison the external load. The pilot reported the wind conditions as "calm" and the temperature 71 degrees Fahrenheit at the time of the accident. Examination of the airframe, systems, and a functional test of the engine revealed no anomalies. The reason for the loss of control was not determined.
Probable cause
the loss of control during external load operations for undetermined reasons.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record DEN05LA131
- Event ID
- 20050912X01431
- Case number
- DEN05LA131
- Dataset
- historical-pre2008
- Source SHA-256
- 89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status, coordinates. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: 1f42752e06c9dcff38bbd981dba6bb007ca27667d5dcc0fd1b2babcfb5758c07; retrieved 2026-09-21T18:54:50.308Z.