# NTSB DEN89LA224: Piper PA-31-350, N3554P, Monument Valley, UT, September 8, 1989

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: September 8, 1989, 09:50 local (15:50 UTC)
- Place: Monument Valley, UT
- Coordinates: 41.010784, -111.669471 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=41.0108&lon=-111.6695&mi=10
- Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 9 uninjured
- Status: Completed, report September 30, 1991
- Report: Approved by Office Director
- NTSB case key (mKey): 17787
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN89LA224
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/17787/pdf
- Page: https://openairdocs.org/ntsb/DEN89LA224

## Probable cause

THE PILOT'S FAILURE TO ADEQUATELY COMPENSATE FOR WINDSHEAR.

## Sequence of events

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

- In flight encounter with weather, approach - vfr pattern - final approach
  - weather condition - windshear (contributing factor)
- Loss of control - in flight, approach - vfr pattern - final approach
  - procedures/directives - not followed, pilot in command (cause)
  - stall - inadvertent, pilot in command
- In flight collision with terrain/water, approach - vfr pattern - final approach

## Analysis

TWO ACFT THAT LANDED AHEAD OF THIS FLIGHT REPORTED WINDSHEAR ON FINAL APPROACH. THE PLT SAID THAT 1 MILE FROM THE THRESHOLD, THE FLIGHT ENCOUNTERED A 15 KT INCREASE IN AIRSPEED, FOLLOWED BY A 15 KT DECREASE IN AIRSPEED. THE PLT SAID THE FLIGHT THEN RETURNED TO A NORMAL APPROACH PROFILE & SPEED. THEN, ON SHORT FINAL, HE HEARD THE STALL HORN AND ADVANCED BOTH THROTTLES FULL FOWARD. THE PLANE ENTERED A STEEP SINK RATE. THE PLANE STRUCK A SAND MOUND WITH THE RIGHT LANDING GEAR. THE PLT WAS ABLE TO RECOVER AND LANDED WITHOUT FURTHER INCIDENT.

## Aircraft

- Registration: [N3554P](https://openairdocs.org/deregistered/N3554P-1992-03-04), registration cancelled 1992-03-04, S/N 318052052 (OpenAirDocs)
- Reported make and model: PIPER PA-31-350
- Registry model: [Piper PA-31-350](https://openairdocs.org/model/piper-pa-31-350) (registry code 7103110) (OpenAirDocs)
- Category: Airplane
- Serial number: 31-8052052
- Engines: LYCOMING TIO-540-J2BD 350 horsepower reciprocating
- Damage: Substantial damage
- Flight: Part 135
- Operator: Aviation Services West, Inc.
- Registered owner: Unknown
- Departed: PGA, PAGE, AZ
- Destination: 71V, MONUMENT VALLEY, UT
- Flight plan: Company VFR
- Airport: 71V, Monument Valley, runway 16, 3,100 × 75 ft, dirt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 30; airline transport; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; flight hours: 3,686 total, 700 in this make and model, 3,386 as pilot in command, 247 in the last 90 days, 65 in the last 30 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: variable at 10 knots, gusting 25
- Visibility: 50 statute miles
- Lowest ceiling: none
- Temperature: -0 °F, dew point -0 °F

## 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 19890908035989A](https://openairdocs.org/incident/19890908035989A), Sep 8, 1989: Piper PA31350, Monument Valley, UT, Substantial damage. Windshear on final. Struck a sand mound short of runway damaging a wing but landed safely on the runway.

## Other investigations on N3554P (1)

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.

- [NTSB DEN90FA066](https://openairdocs.org/ntsb/DEN90FA066), Feb 21, 1990: Piper PA-31-350 (N3554P), Greeley, CO, destroyed. Probable cause: THE IMPROPER IDENTIFICATION OF PARTS IN THE PIPER PA-31-350 SERVICE MANUAL PERTAINING TO THE AILERON CABLES. THIS DISCREPANCY RESULTED IN THE IMPROPER INSTALLATION OF THE AILERON CABLES ON THE RIGHT…

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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