# NTSB MIA08LA199: Eurocopter AS-350-BA, N906BA, Linden, NJ, September 19, 2008

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: September 19, 2008, 17:45 local (21:45 UTC)
- Place: Linden, NJ
- Coordinates: 40.617221, -74.244445 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=40.6172&lon=-74.2444&mi=10
- Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Defining event: [Landing: Collision during takeoff/land](https://openairdocs.org/ntsb-events/490)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report June 17, 2010
- Report: Approved by Office Director
- Parties: FAA/FSDO, American Eurocopter
- NTSB case key (mKey): 68976
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=MIA08LA199
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/68976/pdf
- NTSB docket: https://data.ntsb.gov/Docket?ProjectID=68976
- Page: https://openairdocs.org/ntsb/MIA08LA199

## Probable cause

The flight instructor’s delayed remedial action (flight control inputs) during a practice autorotation/run-on landing resulting in fracture damage to the main rotor system Starflex.

## Findings

NTSB's coded findings; those marked are part of the probable cause.

- [Main rotor system: main rotor head system](https://openairdocs.org/ntsb-findings/01046220): Aircraft › Aircraft propeller/rotor · Damaged/degraded (probable cause); cases with it: [S N I A S AS-350B ECUREUIL, 1 case](https://openairdocs.org/ntsb-findings/01046220/cases.md?model=8680801), [All aircraft, 10 cases](https://openairdocs.org/ntsb-findings/01046220/cases.md)
- [Performance/control parameters](https://openairdocs.org/ntsb-findings/01062000): Aircraft › Aircraft oper/perf/capability · Incorrect use/operation (probable cause); cases with it: [S N I A S AS-350B ECUREUIL, 1 case](https://openairdocs.org/ntsb-findings/01062000/cases.md?model=8680801), [All aircraft, 1,269 cases](https://openairdocs.org/ntsb-findings/01062000/cases.md)
- [Action: delayed action](https://openairdocs.org/ntsb-findings/02041025): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [S N I A S AS-350B ECUREUIL, 1 case](https://openairdocs.org/ntsb-findings/02041025/cases.md?model=8680801), [All aircraft, 894 cases](https://openairdocs.org/ntsb-findings/02041025/cases.md)

## Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event best describes what happened.

- [Maneuvering: Simulated/training event](https://openairdocs.org/ntsb-events/600); cases with it: [S N I A S AS-350B ECUREUIL, 1 case](https://openairdocs.org/ntsb-events/600/sequence.md?model=8680801), [All aircraft, 173 cases](https://openairdocs.org/ntsb-events/600/sequence.md)
- [Autorotation: Attempted remediation/recovery](https://openairdocs.org/ntsb-events/060); cases with it: [S N I A S AS-350B ECUREUIL, 1 case](https://openairdocs.org/ntsb-events/060/sequence.md?model=8680801), [All aircraft, 1,422 cases](https://openairdocs.org/ntsb-events/060/sequence.md)
- [Landing: Collision during takeoff/land](https://openairdocs.org/ntsb-events/490) (defining event); cases with it: [S N I A S AS-350B ECUREUIL, 1 case](https://openairdocs.org/ntsb-events/490/sequence.md?model=8680801), [All aircraft, 1,309 cases](https://openairdocs.org/ntsb-events/490/sequence.md)
- [Landing: Abrupt maneuver](https://openairdocs.org/ntsb-events/270); cases with it: [S N I A S AS-350B ECUREUIL, 1 case](https://openairdocs.org/ntsb-events/270/sequence.md?model=8680801), [All aircraft, 346 cases](https://openairdocs.org/ntsb-events/270/sequence.md)

## Analysis

The flight instructor was monitoring the student pilot during a 180-degree autorotation as part of the flight training. The maneuver was entered at 700 feet above the ground and at 100 knots. Once the intended spot was made for the 'power-on' recovery, the flare was started. As the flight instructor advanced the fuel flow control valve into the flight position, the helicopter started to settle and the low rotor speed horn came on. The flight instructor took over the controls advising the student pilot that it was going to be a run-on landing. During the landing, while in the ground run, the nose of the helicopter pitched forward as the skids dug into the mud. The flight instructor pulled back on the cyclic to prevent the blades from contacting the ground. The helicopter came to rest in the upright position in the grassy area. Post accident inspection of the helicopter’s main rotor system revealed that the 2,167 hours time in service Starflex component had two of its three arms fractured. Examinations of the fracture surfaces revealed no indications of any pre-existing damage to the areas. The fractures were consistent with overstress and unusual loads, which were produced during abrupt flight control inputs with low main rotor RPM.

## Factual narrative

On September 19, 2008, at 1745 eastern daylight time, a Eurocopter AS-350-BA, N906BA, incurred substantial damage during a run on landing at the Linden Airport (LDJ), Linden, New Jersey. The helicopter was operated by Liberty Helicopters. Visual meteorological conditions prevailed and no flight plan was filed for the Title 14 Code of Federal Regulations Part 91, instructional flight. The commercial certificated flight instructor and the commercial certificated student pilot were not injured. The flight instructor stated that the student pilot was performing a 180 degrees autorotation as part of the flight training. The maneuver was entered at 700 feet above the ground and at 100 knots. The 180 degrees turn to the predetermined spot was good. Once the spot was made for the power recovery, the flare was started. The flight instructor advanced the fuel flow control valve into the flight position, the helicopter started to settle and the low rotor speed horn came on. The flight instructor took over the controls and told the student pilot that it was going to be a run on landing. During the landing, while in the ground run, the nose of the helicopter pitched forward when the skids went into the mud. The flight instructor pulled back on the cyclic to prevent the blades from contacting the ground. The helicopter came to rest in the upright position in the grass area. They disembarked on their own after shutting down the helicopter. Post event inspection of the helicopter’s main rotor system revealed that the 2,167 hours time in service Starflex component had two of its three arms fractured. The Starflex was sent to the National Transportation Safety Board Materials Laboratory for a fracture surface examination. There were no indications of any pre-existing damage to the Starflex arms. The fractures were consistent with overstress and unusual loads, which are produced during abrupt flight control inputs with low main rotor RPM.

## Aircraft

- Registration: [N906BA](https://openairdocs.org/deregistered/N906BA-2019-12-02), registration cancelled 2019-12-02, S/N 1479, built 1981 (OpenAirDocs)
- Reported make and model: EUROCOPTER AS-350-BA
- Registry model: [S N I A S AS-350B ECUREUIL](https://openairdocs.org/model/s-n-i-a-s-as-350b-ecureuil) (registry code 8680801) (OpenAirDocs)
- Registry engine: [Turbomeca ARRIEL-1B](https://openairdocs.org/engine/turbomeca-arriel-1b) (registry code 60042, turbo-shaft) (OpenAirDocs)
- Category: Helicopter
- Serial number: 1479
- Airframe hours: 12803
- Engines: Turbomeca Arriel 1B 641 horsepower turbo shaft
- Damage: Substantial damage
- Flight: Instructional, Part 91
- Operator: Liberty Helicopters
- Registered owner: Meridian Consulting I Corp Inc.
- Airworthiness certificate: Standard, Normal
- Last inspection: AAIP, September 18, 2008, 17 hours before
- Departed: LDJ, Linden, NJ
- Destination: LDJ, Linden, NJ
- Airport: LDJ, Linden Airport

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Flight instructor; age 38; injuries: none; flight instructor, commercial; instrument ratings: helicopter; medical: class 2, without waivers/limitations; last flight review August 17, 2008; seat: left; flight hours: 2,280 total, 1,074 in this make and model, 152 in the last 90 days, 52 in the last 30 days, 4 in the last 24 hours
- Student pilot; age 29; injuries: none; flight instructor, commercial; instrument ratings: helicopter; medical: class 2, with waivers/limitations; seat: right; flight hours: 1,104 total, 5 in this make and model, 144 in the last 90 days, 36 in the last 30 days, 2 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 60° at 7 knots
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 68 °F, dew point 50 °F
- Altimeter: 30.39 inHg
- Observed at: LDJ

## 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 20080919850569A](https://openairdocs.org/incident/20080919850569A), Sep 19, 2008: Snias AS350B, Linden, NJ, Substantial damage. (-23) Training captain was administering new hire check ride. New hire pilot allowed rotor r.p.m. to decay dangerously low. Training captain was too late in…

## Docket (7 files)

The files NTSB released with the investigation on April 23, 2010, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=68976. 8.2 MB in all.

- Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 758 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40328225&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF
- Reports from Federal Agencies: Federal Aviation Administration Inspector Statement. (item 2, .PDF, 75 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40328226&FileExtension=.PDF&FileName=Reports%20from%20Federal%20Agencies%3A%20Federal%20Aviation%20Administration%20Inspector%20Statement.-Redacted.PDF
- Reports from Parties to the Investigation: Excerpts From American Eurocopter on Scene Field Notes. (item 3, .PDF, 320 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40328227&FileExtension=.PDF&FileName=Reports%20from%20Parties%20to%20the%20Investigation%3A%20Excerpts%20From%20%20American%20Eurocopter%20on%20Scene%20Field%20Notes.-Redacted.PDF
- Materials Laboratory Factual Report 09-020, Eurocopter AS350 Main Rotor Starflex (item 4, .PDF, 6.8 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40311601&FileExtension=.PDF&FileName=Materials%20Laboratory%20Factual%20Report%2009-020,%20Eurocopter%20AS350%20Main%20Rotor%20Starflex-Master.PDF
- Miscellaneous: Excerpts From the Helicopter's Aircraft Logbook. (item 5, .PDF, 146 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40328228&FileExtension=.PDF&FileName=Miscellaneous%3A%20Excerpts%20From%20the%20Helicopter%27s%20Aircraft%20Logbook.-Redacted.PDF
- Statement of Party Representatives to NTSB Investigation (item 6, .PDF, 74 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40328229&FileExtension=.PDF&FileName=Statement%20of%20Party%20Representatives%20to%20NTSB%20Investigation-Redacted.PDF
- Release of Aircraft Wreckage, NTSB Form 6120.15 (item 7, .PDF, 84 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40328231&FileExtension=.PDF&FileName=Release%20of%20Aircraft%20Wreckage,%20NTSB%20Form%206120.15-Redacted.PDF

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.

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