# NTSB ATL91IA024: Cessna S550, N185SF, Columbus, GA, December 1, 1990

- Type: NTSB incident investigation
- Classification: Incident · No injuries · Incident investigation · Final report
- Date: November 30, 1990, 19:25 local (Dec 1, 1990, 00:25 UTC)
- Place: Columbus, GA
- Coordinates: 32.550193, -84.920104 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=32.5502&lon=-84.9201&mi=10
- Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 5 uninjured
- Status: Completed, report December 30, 1992
- Report: Approved by Office Director
- Safety recommendations: Yes
- NTSB case key (mKey): 8342
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ATL91IA024
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/8342/pdf
- Page: https://openairdocs.org/ntsb/ATL91IA024

## Probable cause

A FATIGUE FAILURE OF A SPOT WELD ON THE GAS GENERATOR CASE, WHICH RESULTED IN AN ENGINE EXPLOSION.

## Analysis

THE PILOT ABORTED A NIGHT TAKE OFF ROLL AFTER THE RIGHT ENGINE EXPLODED. EXAMINATION OF THE RIGHT ENGINE DISCLOSED THAT THE ENGINE COWLING WAS DISPLACED ABOUT 12 INCHES FROM ITS NORMALLY INSTALLED POSITION. FURTHER EXAMINATION INDICATED THAT THE OUTER BYPASS DUCT AND GAS GENERATOR CASE WERE BURST OPEN FROM THE 12:00 TO 5:00 O'CLOCK POSITION. THE RUPTURE OCCURRED AS THE AIRPLANE ACCELERATED THROUGH 84 KNOTS ON THE TAKEOFF ROLL. THE INVESTIGATION DISCLOSED THAT THE GAS GENERATOR FAILED DUE TO SPOT WELD FATIGUE FAILURE, AND THE EXITING GASES UNDER HIGH PRESSURE BURST THE OUTER BYPASS DUCT, CAUSING EXPLOSION DAMAGE.

## 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 - roll/run
  - combustion assembly - failure,partial (cause)

## Aircraft

- Registration: [N185SF](https://openairdocs.org/aircraft/N185SF), registered now, S/N 18502922, built 1976 (OpenAirDocs)
- Reported make and model: CESSNA S550
- Registry model: [Cessna A185F](https://openairdocs.org/model/cessna-a185f) (registry code 2072821) (OpenAirDocs)
- Registry engine: [Continental IO-520 series](https://openairdocs.org/engine/continental-io-520-series) (registry code 17032, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 550-0029
- Engines: P&W 2500 lbs thrust turbo fan
- Damage: Minor damage
- Flight: Business, Part 91
- Operator: Sovran Bank Na
- Destination: PDK, CHAMBLEE, GA
- Flight plan: IFR
- Airport: CSG, Columbus Metro, runway 5, 6,998 × 150 ft, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 45; commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; flight hours: 6,500 total, 2,400 in this make and model, 5,200 as pilot in command, 120 in the last 90 days, 40 in the last 30 days, 3 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Night/dark
- Wind: 60° at 6 knots
- Visibility: 4 statute miles
- Lowest ceiling: none
- Temperature: -0 °F, dew point -0 °F
- Observed at: CSG

## 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 19901130056909I](https://openairdocs.org/incident/19901130056909I), Nov 30, 1990: Cessna S550, Columbus, GA, Minor damage. Right engine failed on takeoff. Aborted. Engine had a hole from combustion chamber explosion.

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

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