# NTSB ATL92FA039: Cessna 421C, N40JK, Atlantic Ocean (Atlantic Ocean), January 13, 1992

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Field investigation · Final report
- Date: January 13, 1992, 16:06 local (21:06 UTC)
- Place: Atlantic Ocean (Atlantic Ocean)
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 5 fatal
- Status: Completed, report October 8, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 8494
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ATL92FA039
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/8494/pdf
- Page: https://openairdocs.org/ntsb/ATL92FA039

## Probable cause

THE PILOT'S INADEQUATE WEATHER EVALUATION, AND HIS CONTINUED FLIGHT INTO KNOWN ADVERSE WEATHER CONDITIONS. FACTORS WERE: THE IMPROPER WEATHER BRIEFING BY A FLIGHT SERVICE STATION SPECIALIST, AND LEVEL III THUNDERSTORMS.

## Sequence of events

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

- In flight encounter with weather, cruise - normal
  - preflight briefing service - improper, atc personnel(fss) (contributing factor)
  - weather evaluation - inadequate, pilot in command (cause)
  - weather condition - thunderstorm,level iii (contributing factor)
  - hazardous weather advisory - issued, atc personnel(dep/apch)
  - flight into known adverse weather - continued, pilot in command (cause)
- Loss of control - in flight, maneuvering - turn to reverse direction
- Airframe/component/system failure/malfunction, descent - uncontrolled
  - design stress limits of aircraft - exceeded, pilot in command
  - wing - overload
  - wing - separation
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

AT 0716, THE PILOT RCVD A WX BRIEF FOR A PROPOSED TAKEOFF OF 1130. THE FSS BRIEFER PROVIDED INFO ON TSTMS FORECAST IN GA & FL. NO INFO WAS PROVIDED ABOUT FORECAST LINES & CLUSTERS OF TSTMS IN SC CSTL PLAINS & SERN GA. EN ROUTE, THE PILOT WAS GIVEN INFO ABOUT LEVEL III TSTMS ACROSS THE PROJECTED FLIGHT PATH BY BEAUFORT & SAVANNAH APPCH CNTRL. ATC RADAR DATA REVEALED THAT THE ACFT FLEW THE ROUTE CONTAINED IN THE FLIGHT PLAN CLEARANCE. RADIO TRANSMISSIONS FROM THE ACFT INDICATED THAT ONBOARD WX RADAR WAS BEING USED. ATC RADAR DATA & RADIO COMMUNICATIONS INDICATED THAT THE ACFT ENTERED A TSTM, THEN MADE A 180 DEGREE TURN TO EXIT THE STORM. EXAMINATION OF THE WRECKAGE REVEALED PLASTIC DEFORMATION OF THE WINGS INBOARD OF THE ENGINES IN AN UPWARD DIRECTION. ALSO, BOTH WINGS BROKE OFF OUTBOARD OF THE ENGINES IN A DOWNWARD DIRECTION. THE HORIZONTAL STAB & ELEVATOR WERE NOT RECOVERED. THERE WAS FUSELAGE DAMAGE WHICH INDICATED THAT THE HORIZONTAL STAB SEPARATED AFT & DOWN.

## Aircraft

- Registration: [N40JK](https://openairdocs.org/deregistered/N40JK-2013-06-04), registration cancelled 2013-06-04, S/N 421C0441, built 1977 (OpenAirDocs)
- Reported make and model: CESSNA 421C
- Registry model: [Cessna 421C](https://openairdocs.org/model/cessna-421c) (registry code 2076016) (OpenAirDocs)
- Registry engine: [Continental GTSI0-520-F-K](https://openairdocs.org/engine/continental-gtsi0-520-f-k) (registry code 17031, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 42100441
- Engines: CONTINENTAL GTSIO-520-L 375 horsepower reciprocating
- Damage: Destroyed
- Flight: Personal, Part 91
- Operator: Williamson, J. M.
- Registered owner: Williamson, J. M.
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, June 26, 1991
- Departed: MIV, MILVILLE, NJ
- Destination: X26, SEBASTIAN, FL
- Flight plan: IFR

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 60; private; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 3, valid medical--w/ waivers/lim; toxicology performed; flight hours: 3,064 total, 500 in this make and model

## Weather

- Conditions: Instrument (IMC), Day
- Wind: calm
- Visibility: 1 statute miles
- Lowest ceiling: 1,200 ft overcast
- Temperature: 59 °F, dew point 59 °F
- Altimeter: 29.00 inHg
- Observed at: SSI, 30 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 19920113000469A](https://openairdocs.org/incident/19920113000469A), Jan 13, 1992: Cessna 421C, Brunswick, GA, Destroyed, 5 fatal. Continued into area of known thunderstorms. Lost control and broke up in flight. Sigmets in effect for thunderstrom

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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