# NTSB FTW92FA169: Rockwell 690B, N690JC, Konawa, OK, June 25, 1992

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Field investigation · Final report
- Date: June 25, 1992, 08:33 local (13:33 UTC)
- Place: Konawa, OK
- Coordinates: 34.950294, -96.749404 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=34.9503&lon=-96.7494&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 1 fatal
- Status: Completed, report January 4, 1994
- Report: Approved by Office Director
- NTSB case key (mKey): 18364
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW92FA169
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/18364/pdf
- Page: https://openairdocs.org/ntsb/FTW92FA169

## Probable cause

THE PILOT'S FAILURE TO MAINTAIN CONTROL OF THE AIRPLANE WHICH RESULTED IN AN INADVERTENT SPIRAL AND SUBSEQUENT RAPID DESCENT. THE DESIGN STRESS LIMITS OF THE AIRFRAME WERE EXCEEDED RESULTING IN AN OVERLOAD FAILURE OF THE EMPENNAGE. FACTORS RELATED TO THE ACCIDENT WERE: TURBULENCE AND THE PILOT'S PHYSICAL IMPAIRMENT DUE TO DRUGS.

## Sequence of events

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

- Loss of control - in flight, climb - to cruise
  - weather condition - turbulence(thunderstorms) (contributing factor)
  - aircraft control - not maintained, pilot in command (cause)
  - impairment(drugs), pilot in command (contributing factor)
  - spiral - inadvertent, pilot in command
- Loss of engine power, descent - uncontrolled
  - 1 engine
  - reason for occurrence undetermined (cause)
- Airframe/component/system failure/malfunction, descent - uncontrolled
  - design stress limits of aircraft - exceeded (cause)
  - stabilizer - overload
  - stabilizer - separation
  - flt control syst,rudder - overload
  - flt control syst,rudder - separation
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

AS THE AIRPLANE WAS DEVIATING AROUND LOW INTENSITY WEATHER RETURNS, AND PASSING THROUGH 20,500 FT DURING CLIMB OUT, IT DEPARTED CONTROLLED FLIGHT AND ENTERED A RIGHT SPIRAL. DESCENT RATES EXCEEDED 16,600 FPM DURING THE DESCENT FROM 18,300 FT TO 3,900 FT AND THEN SLOWED. WITNESSES STATED THEY SAW THE AIRPLANE DESCEND FROM THE CLOUDS IN A RIGHT FLAP SPIN. THE EMPENNAGE HAD SEPARATED FROM THE AIRPLANE IN PIECES. PIECES OF THE WRECKAGE WERE FOUND UP TO 1.5 MI FROM THE PRIMARY IMPACT POINT. BOTH WINGS REMAINED ATTACHED. THE RIGHT ENGINE WAS FLAMED OUT, AND THE PROP WAS FEATHERED AT IMPACT. NO MECHANICAL REASON FOR THE FLAMEOUT COULD BE DETERMINED. AT NO TIME DID THE PILOT INDICATE HE WAS HAVING DIFFICULTIES. THE NTSB WEATHER STUDY INDICATED THAT MODERATE TURBULENCE WAS PRESENT IN THE AREA. THE PILOT'S TOXICOLOGY TESTS FOUND 0.151 UG/ML OF CHLORPHENIRAMINE IN THE BLOOD; NORMAL THERAPEUTIC CONCENTRATION IS 0.01 TO 0.04. EFFECTS OF OVERDOSAGE INCLUDE SEDATION, DIMINISHED MENTAL ALERTNESS, AND CARDIOVASCULAR COLLAPSE TO STIMULATION.

## Aircraft

- Registration: [N690JC](https://openairdocs.org/deregistered/N690JC-1992-08-28), registration cancelled 1992-08-28, S/N 11479 (OpenAirDocs)
- Reported make and model: Rockwell 690B
- Registry model: [Rockwell International 690B](https://openairdocs.org/model/rockwell-international-690b) (registry code 7630516) (OpenAirDocs)
- Category: Airplane
- Serial number: 11479
- Airframe hours: 3355
- Engines: GARRETT TPE-331-5-251 717 horsepower turbo prop
- Damage: Destroyed
- Fire: On-Ground
- Flight: Ferry, Part 91
- Operator: Aircraft Sales International
- Registered owner: Prime Inc.
- Airworthiness certificate: Standard, Normal
- Last inspection: 100 hour, March 27, 1992, 28 hours before
- Departed: OUN, NORMAN, OK
- Destination: FLL, FT. LAUDERDALE, FL
- Flight plan: IFR

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 65; flight instructor, airline transport, military, commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane, helicopter; medical: class 2, valid medical--w/ waivers/lim; seat: left; toxicology performed; flight hours: 8,857 total, 98 in this make and model, 8,486 as pilot in command, 77 in the last 90 days, 15 in the last 30 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 120° at 8 knots
- Lowest ceiling: 3,400 ft broken
- Temperature: 70 °F
- Altimeter: 29.00 inHg
- Observed at: ADM, 35 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 19920625021739A](https://openairdocs.org/incident/19920625021739A), Jun 25, 1992: Gulstm 690B, Konowa, OK, Destroyed, 1 fatal. Lost control in thunderstorm area. Empannage failed. Entered flat spin. Right engine flame out.

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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