# NTSB DEN89FA064: Convair 580, N73160, Buena Vista, CO, January 20, 1989

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Field investigation · Final report
- Date: January 20, 1989, 09:25 local (16:25 UTC)
- Place: Buena Vista, CO
- Coordinates: 38.830535, -106.140365 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=38.8305&lon=-106.1404&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 5 minor, 24 uninjured
- Status: Completed, report January 22, 1991
- Report: Approved by Office Director
- NTSB case key (mKey): 17577
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN89FA064
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/17577/pdf
- Page: https://openairdocs.org/ntsb/DEN89FA064

## Probable cause

INADVERTENT DEACTIVATION OF FUEL TO THE LEFT ENGINE AS THE PILOT WAS MAKING A PRECAUTIONARY SHUTDOWN OF THE RIGHT ENGINE, AND HIS FAILURE TO FOLLOW THE EMERGENCY CHECKLIST PROCEDURE.  RELATED FACTORS WERE: LOW GEARBOX OIL PRESSURE (AT FLIGHT ALTITUDE), AND UNEVEN TERRAIN THAT WAS ENCOUNTERED DURING THE EMERGENCY LANDING.

## Sequence of events

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

- Loss of engine power(total) - nonmechanical, cruise - normal
  - 1 engine
  - lubricating system - pressure too low (contributing factor)
  - propeller feathering - intentional
- Loss of engine power(total) - nonmechanical, cruise
  - all engines
  - fuel supply - inadvertent deactivation, pilot in command (cause)
- Forced landing, descent - emergency
  - emergency procedure - improper, pilot in command (cause)
  - checklist - not followed, pilot in command (cause)
- On ground/water encounter with terrain/water, landing - roll
  - terrain condition - rough/uneven (contributing factor)

## Analysis

DRG FLT, CREW SHTDN RGT ENG WHEN WARNING LGT FOR GEARBOX OIL PRES ILLUMINATED & PRES WAS NOTED BLO MIN LMT OF 130 PSI. SHORTLY AFTER SECURING RGT ENG, L ENG LOST PWR. (FUEL TANK SHUTOFF VLV SWS & FUEL X-FEED VLV SW WERE LCTD NR EACH OTR.) ATMTS TO RESTART L ENG WERE UNSUCCESSFUL. WITH LACK OF AC ELEC PWR, CAPT COULD NOT UNFEATHER RGT ENG FOR RESTART. DRG EMERG LNDG, ACFT WAS DMGD ON UNEVEN TRRN. OPNL CHECK OF RGT ENG (AT GND LVL) REVEALED NO MALFUNCTION THAT WOULD HAVE PREVENTED NML OPN. EXAM OF L ENG REVEALED TURBINE SECTION HAD OVERHEATED & TURBINE BLADES HAD SEVERE HEAT DMG. CAPT SAIDTHAT WHEN HE TRIED TO RESTART L ENG, FUEL VLVS WERE IN NORMAL PSN & PWR LEVER WAS 1' ABV IDLE. HE RECALLED AN ENG RPM OF8000, BUT DIDN'T RECALL IF HE HAD USED FEATHER BUTTON TO REDUCE RPM TO 3000 (AS DRCTD BY CHECKLIST). HE VERIFIED FUEL SWS WERE 'ON' & HE TRIED TO X-FEED FUEL (IN EVENT OF BLOCKAGE). X-FEEDING OF FUEL WAS NOT PART OF RESTART PROC. FLT MAN-UAL CAUTIONED ABT IMPORTANCE OF REDUCING PWR TO FLT IDLE, TO DECREASE FUEL FLOW TO ENG & MINIMIZE POSSIBLE OVERHEATING.

## Aircraft

- Registration: [N73160](https://openairdocs.org/deregistered/N73160-1991-04-01), registration cancelled 1991-04-01, S/N 336 (OpenAirDocs)
- Reported make and model: CONVAIR 580
- Registry model: [Convair 440](https://openairdocs.org/model/convair-440) (registry code 2422902) (OpenAirDocs)
- Category: Airplane
- Serial number: 336
- Airframe hours: 54108
- Engines: ALLISON 501-D13H 3750 horsepower turbo prop
- Damage: Substantial damage
- Flight: Part 121
- Operator: Aspen Airways, doing business as United Express
- Registered owner: Sierra Pacific Airlines Inc
- Airworthiness certificate: Standard, Transport
- Last inspection: Continuous airworthiness, December 7, 1988
- Departed: DEN, DENVER, CO
- Destination: DRO, DURANGO, CO
- Flight plan: IFR

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 55; commercial, airline transport, flight instructor; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--w/ waivers/lim; seat: left; flight hours: 18,644 total, 6,224 in this make and model, 12,138 as pilot in command, 173 in the last 90 days, 76 in the last 30 days, 5 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 50 statute miles
- Lowest ceiling: none
- Temperature: 1 °F, dew point 1 °F
- Altimeter: 30.00 inHg
- Observed at: LXV, 2 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 19890120001309A](https://openairdocs.org/incident/19890120001309A), Jan 20, 1989: Cvac 440, Buena Vista, CO, Substantial damage. Feathered right engine on power loss. Left engine inadvertently shut down. Glided to landing on dirt road.

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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