# NTSB CHI90IA181: Bell 206A, N206AT, Lake Ozark, MO, July 19, 1990

- Type: NTSB incident investigation
- Classification: Incident · No injuries · Incident investigation · Final report
- Date: July 19, 1990, 13:15 local (18:15 UTC)
- Place: Lake Ozark, MO
- Coordinates: 38.180652, -92.620986 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=38.1807&lon=-92.6210&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 4 uninjured
- Status: Completed, report December 30, 1992
- Report: Approved by Office Director
- NTSB case key (mKey): 14569
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI90IA181
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/14569/pdf
- Page: https://openairdocs.org/ntsb/CHI90IA181

## Probable cause

COMPRESSION ASSEMBLY BLADE AND EMERGENCY FLOATATION GEAR FAILURE.

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- Loss of engine power(total) - mech failure/malf, takeoff - initial climb
  - compressor assembly,blade - failure,total (cause)
- Forced landing, descent - emergency
- In flight collision with terrain/water, landing
  - terrain condition - water (contributing factor)
  - misc rotorcraft,emergency floatation gear - failure,total (cause)

## Analysis

SHORTLY AFTER LIFT-OFF, OVER WATER, THE HELICOPTER'S ENGINE FAILED. AN EMERGENCY LANDING WAS ATTEMPTED ON THE WATER, BUT THE EMERGENCY INFLATABLE FLOATS FAILED TO DEPLOY. THE ACFT SANK, BUT ALL FOUR OCCUPANTS ESCAPED WITHOUT INJURY. THE HELICOPTER SUSTAINED ONLY MINOR DAMAGE. POST ACCIDENT INVESTIGATION REVEALED THE COMPRESSOR BLADES, AFTER THE FIRST STAGE, HAD FAILED.

## Aircraft

- Registration: [N206AT](https://openairdocs.org/deregistered/N206AT-1992-05-20), registration cancelled 1992-05-20, S/N 504 (OpenAirDocs)
- Reported make and model: BELL 206A
- Registry model: [Bell 206B](https://openairdocs.org/model/bell-206b) (registry code 1181511) (OpenAirDocs)
- Category: Helicopter
- Serial number: 504
- Engines: ALLISON 250-C20 317 horsepower turbo shaft
- Damage: Minor damage
- Flight: Business, Part 91
- Operator: Ozark Helicopter

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 33; airline transport; airplane ratings: single-engine land; instrument ratings: helicopter; medical: class 1, valid medical--no waivers/lim.; flight hours: 3,780 total, 2,105 in this make and model, 3,410 as pilot in command, 54 in the last 90 days, 27 in the last 30 days, 3 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 210° at 5 knots
- Visibility: 20 statute miles
- Lowest ceiling: none
- Temperature: -0 °F, dew point -0 °F

## FAA reports on this event (1)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Incident 19900719027489I](https://openairdocs.org/incident/19900719027489I), Jul 19, 1990: Bell 206B, Lake Ozark, MO, Minor damage. Engine failed on liftoff. Autorotated to water floats,did not deploy. Sank. Had engine turbine failure.

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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