IAD99GA056 · Eurocopter AS-350
Eurocopter AS-350 · Accident: loss of control in flight while maneuvering
From Long Island MacArthur Airport (ISP) to an unrecorded destination
Event
- NTSB case
- IAD99GA056
- 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
- 0
- 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
Eurocopter AS-350
- Aircraft type
- Eurocopter AS-350
- 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
- N211PD
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Long Island MacArthur Airport (ISP)To not recorded
- 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 91: General Aviation
- 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 · hover
- 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
- 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
- Pilot in command › Aircraft control, not maintained
- Pilot in command(cfi) › Supervision, inadequate
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot was completing transition training in the helicopter with a flight instructor. The pilot initiated a simulated hydraulics failure out of sequence with the flight-training guide and flew the helicopter to the ground without incident. With hydraulics still disabled, the pilot was instructed to hover-taxi approximately 100 feet, perform a left pedal turn, and taxi back. The pilot successfully hovered forward; however, during the turn to hover back to the start point, the pilot could not maintain control of the helicopter. The instructor attempted recovery, but the helicopter rolled and the main rotor blades struck terrain. Orientation of the helicopter following the turn resulted in a 14-knot tailwind. Examination of the wreckage revealed no pre-impact anomalies. Testing of the hydraulic servos revealed high fluid flow rates, but no operational deficiencies. Approximately 1 year after the accident, the helicopter manufacturer removed in ground-effect maneuvers with the hydraulics off from their flight-training guide.
Probable cause
The pilot's loss of control during hydraulics-off hovering flight and the instructor's inadequate supervision of the maneuver. A factor was the tailwind.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record IAD99GA056
- Event ID
- 20001212X19539
- Case number
- IAD99GA056
- 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. 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: 9171ebd2f0f1013c6e313a668a67c6a588dc01dfe7f6f16f3c8f85febd45f661; retrieved 2026-09-21T20:26:46.015Z.