# NTSB CHI89FA078: Cessna 208A, N9637F, Mt. Zion, IL, April 27, 1989

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Field investigation · Final report
- Date: April 26, 1989, 21:40 local (Apr 27, 1989, 02:40 UTC)
- Place: Mt. Zion, IL
- Coordinates: 39.769958, -88.870613 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=39.7700&lon=-88.8706&mi=10
- Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 1 minor
- Status: Completed, report January 23, 1992
- Report: Approved by Office Director
- NTSB case key (mKey): 14251
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI89FA078
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/14251/pdf
- Page: https://openairdocs.org/ntsb/CHI89FA078

## Probable cause

THE PILOT'S INTENTIONAL FLIGHT INTO KNOWN ADVERSE WEATHER. CONTRIBUTING FACTORS WERE THE PILOT'S POOR EVALUATION OF THE WEATHER INFORMATION GIVEN HIM BY THE AIR TRAFFIC CONTROLLERS.

## Sequence of events

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

- In flight encounter with weather, approach - faf/outer marker to threshold (ifr)
  - preflight planning/preparation - inadequate, pilot in command (contributing factor)
  - weather condition - thunderstorm (contributing factor)
  - weather condition - rain (contributing factor)
  - weather condition - high wind (contributing factor)
  - weather condition - gusts (contributing factor)
  - weather condition - windshear (contributing factor)
  - weather condition - downdraft (contributing factor)
  - weather condition - turbulence(thunderstorms) (contributing factor)
- Loss of control - in flight, approach - faf/outer marker to threshold (ifr)
  - flight into known adverse weather - intentional, pilot in command (cause)
  - aircraft control - uncontrolled, pilot in command (cause)
- In flight collision with terrain/water, approach - faf/outer marker to threshold (ifr)

## Analysis

DEPARTED MARION WITHOUT A WX BRIEFING. PLT ADVISED DURING APPROACH THAT LAST PERSON MAKING APPROACH REPORTED MODERATE TO SEVERE TURBULENCE ON FINAL. SUBSEQUENTLY CLEARED TO LAND AND GIVEN WIND 360 AT 30 GUSTING 40. ALSO ADVISED THAT ANOTHER AIRCRAFT REPORTED A 20KT WINDSHEAR ON FINAL. THE PILOT REPORTED THAT WHEN HE HAD DESCENDED TO 1500 FEET MSL, THE AIRCRAFT ENCOUNTERED STRONG TURBULENCE AND THE AIRSPEED WENT FROM STALL TO REDLINE. DESPITE ADJUSTMENT TO FLAPS AND THROTTLE, THE AIRPLANE WAS UNCONTROLLABLE.

## Aircraft

- Registration: [N9637F](https://openairdocs.org/deregistered/N9637F-2012-11-27), registration cancelled 2012-11-27, S/N 20800120, built 1987 (OpenAirDocs)
- Reported make and model: CESSNA 208A
- Registry model: [Cessna 208](https://openairdocs.org/model/cessna-208) (registry code 2073702) (OpenAirDocs)
- Registry engine: [Pratt & Whitney Canada PT6A-60A](https://openairdocs.org/engine/pratt-whitney-canada-pt6a-60a) (registry code 52043, turbo-prop) (OpenAirDocs)
- Category: Airplane
- Serial number: 20800120
- Airframe hours: 742
- Engines: P&W PT6A-114 600 horsepower turbo prop
- Damage: Substantial damage
- Flight: Part 135
- Operator: Dupage Airport Authority, doing business as Planemaster Services
- Registered owner: Cessna Finance Corporation
- Airworthiness certificate: Standard, Normal
- Last inspection: Continuous airworthiness, March 27, 1989, 43 hours before
- Departed: MWA, MARION, IL
- Flight plan: IFR
- Airport: DEC, Decatur, runway 36, 5,300 × 150 ft, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 32; flight instructor, commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: left; flight hours: 7,100 total, 800 in this make and model, 7,000 as pilot in command

## Weather

- Conditions: Instrument (IMC), Night/dark
- Wind: 10° at 25 knots, gusting 40
- Visibility: 1 statute miles
- Lowest ceiling: 2,000 ft
- Temperature: 63 °F, dew point 59 °F
- Altimeter: 29.00 inHg
- Observed at: DEC, 4 nm away

## 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 19890426010049A](https://openairdocs.org/incident/19890426010049A), Apr 26, 1989: Cessna 208A, Decatur, IL, Substantial damage. Lost control in severe turbulence on IFR approach. Impacted in open field. Squall line was approaching airport.

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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