# NTSB ATL90FA001: Beech C90, N43GT, Chamblee, GA, October 1, 1989

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Field investigation · Final report
- Date: October 1, 1989, 16:42 local (20:42 UTC)
- Place: Chamblee, GA
- Coordinates: 33.899345, -84.300712 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=33.8993&lon=-84.3007&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 2 fatal
- Status: Completed, report June 30, 1992
- Report: Approved by Office Director
- NTSB case key (mKey): 8098
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ATL90FA001
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/8098/pdf
- Page: https://openairdocs.org/ntsb/ATL90FA001

## Probable cause

MALFUNCTION OF ONE OR MORE FLIGHT INSTRUMENTS FOR AN UNDETERMINED REASON, FAILUE OF THE PILOT TO MAINTAIN CONTROL OF THE AIRCRAFT WITH PARTIAL PANEL INSTRUMENTS AFTER BECOMING SPATIALLY DISORIENTED, AND HIS EXCEEDING THE DESIGN STRESS LIMITS OF THE AIRCRAFT.  THE WEATHER (LOW CEILING) AND MALFUNCTIONING DIRECTIONAL GYRO WERE RELATED FACTORS.

## Sequence of events

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

- Airframe/component/system failure/malfunction, climb
  - flight/nav instruments - undetermined (cause)
  - maintenance,inspection - not performed
  - flight/nav instruments,directional gyro - inoperative (contributing factor)
- Loss of control - in flight, maneuvering
  - weather condition - low ceiling (contributing factor)
  - aircraft control - not maintained, pilot in command (cause)
  - spatial disorientation, pilot in command (cause)
- Airframe/component/system failure/malfunction, maneuvering
  - design stress limits of aircraft - exceeded, pilot in command (cause)
  - wing - overload
  - wing - separation
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

AFTER TAKING OFF, THE PLT ESTABLISHED RADIO CONTACT WITH DEP CTL & RPRTD A DIRECTIONAL GYRO PROBLEM. SECONDS LATER, HE RPRTD THAT HE WAS LOSING ALL INSTRUMENTS. DEP CTL ATTEMPTED TO PROVIDE NO-GYRO VECTORS. THE PLT WAS INSTRUCTED TO MAKE A FREQ CHANGE. SOON THEREAFTER, RADIO & RADAR CONTACT WERE LOST & THE ACFT CRASHED. BEFORE CRASHING THE ACFT WAS OBSERVED IN A ROLLING ATTITUDE. WRECKAGE WAS FOUND SCATTERED OVER A 600' BY 150' AREA. AN EXAM REVEALED THE RIGHT WING HAD SEPD IN FLT. THERE WAS EVIDENCE THAT THE RIGHT WING HAD FAILED IN AN UPWARD (POSITIVE) DRCTN. THE PLT'S ATTITUDE GYRO WAS DAMAGED DURING IMPACT, BUT NO ROTATIONAL DAMAGE WAS NOTED. THE PLT'S ATTITUDE INDCR & COPLT'S TURN INDCR WERE AIR DRIVEN, THE PLT'S TURN INDCR WAS DC POWERED & THE COPLT'S ATTITUDE INDCR WAS AC POWERED. THE MAINTENANCE LOG DID NOT HAVE A CURRENT STATIC/ALTIMETER & TRANSPONDER CHECK.

## Aircraft

- Registration: [N43GT](https://openairdocs.org/deregistered/N43GT-1990-06-14), registration cancelled 1990-06-14, S/N LJ652 (OpenAirDocs)
- Reported make and model: BEECH C90
- Registry model: [Beech C90](https://openairdocs.org/model/beech-c90) (registry code 1152913) (OpenAirDocs)
- Category: Airplane
- Serial number: LJ-652
- Airframe hours: 4272
- Engines: P&W PT6A-20 579 horsepower turbo prop
- Damage: Destroyed
- Flight: Personal, Part 91
- Operator: Roy Beatty
- Last inspection: 100 hour, April 3, 1989, 136 hours before
- Departed: PDK, CHAMBLEE, GA
- Destination: ORL, ORLANDO, FL
- Flight plan: IFR
- Airport: PDK, Dekalb Peachtree

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 48; airline transport; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; toxicology performed; flight hours: 2,000 total, 400 in this make and model

## Weather

- Conditions: Instrument (IMC), Day
- Wind: 110° at 7 knots
- Visibility: 2 statute miles
- Lowest ceiling: 700 ft broken
- Temperature: -0 °F, dew point -0 °F
- Observed at: PDK, 1 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 19891001037139A](https://openairdocs.org/incident/19891001037139A), Oct 1, 1989: Beech C90, Atlanta, GA, Destroyed, 2 fatal. Lost altitude gyros on climb. Lost control. Sprial dive lost wing tip. Inverter failed.

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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