# NTSB SEA91FA170: Piper PA-28-140, N501FL, Driggs, ID, July 14, 1991

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Field investigation · Final report
- Date: July 14, 1991, 11:50 local (17:50 UTC)
- Place: Driggs, ID
- Coordinates: 43.730319, -111.220886 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=43.7303&lon=-111.2209&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 2 fatal
- Status: Completed, report February 8, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 41327
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA91FA170
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/41327/pdf
- Page: https://openairdocs.org/ntsb/SEA91FA170

## Probable cause

THE PILOT'S POOR INFLIGHT DECISION AND HIS IMPROPER COMPENSATION FOR WIND. FACTORS WERE RISING, MOUNTAINOUS TERRAIN; HIGH, GUSTY WINDS; AND A HIGH DENSITY ALTITUDE.

## Sequence of events

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

- In flight collision with terrain/water, climb
  - in-flight planning/decision - poor, pilot in command (cause)
  - compensation for wind conditions - improper, pilot in command (cause)
  - terrain condition - rising (contributing factor)
  - terrain condition - mountainous/hilly (contributing factor)
  - weather condition - high density altitude (contributing factor)
  - weather condition - high wind (contributing factor)
  - weather condition - gusts (contributing factor)

## Analysis

EVEN THOUGH A LOCAL CFI ATTEMPTED TO DISCOURAGE HIM FROM DOING SO, THE PIPER PA-28-140 PILOT DEPARTED THE UNCONTROLLED AIRPORT, WITH THE AIRCRAFT NEAR CERTIFIED GROSS WEIGHT, WHEN THE DENSITY ALTITUDE WAS OVER 10,000 MSL.  WIDELY SCATTERED TOWERING THUNDERSTORMS WERE BUILDING IN THE AREA, AS THE PILOT ATTEMPTED TO CLIMB THROUGH A NARROW MOUNTAIN VALLEY.  WINDS AT THE TIME OF THE ACCIDENT WERE REPORTED TO BE GREATER THAN 20 KNOTS, WITH HIGHER GUSTS AND RAPIDLY CHANGING DIRECTION.  JUST AFTER PASSING THE ENTRANCE TO THE VALLEY THE AIRCRAFT IMPACTED THE TERRAIN AT 7000 FEET MSL.

## Aircraft

- Registration: [N501FL](https://openairdocs.org/deregistered/N501FL-2012-12-10), registration cancelled 2012-12-10, S/N 28-7125320, built 1971 (OpenAirDocs)
- Reported make and model: PIPER PA-28-140
- Registry model: [Piper PA-28-140](https://openairdocs.org/model/piper-pa-28-140) (registry code 7102802) (OpenAirDocs)
- Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 28-7125320
- Engines: LYCOMING O-320-E3D 150 horsepower reciprocating
- Damage: Destroyed
- Fire: On-Ground
- Flight: Personal, Part 91
- Operator: Jim Fields
- Registered owner: Jim Fields
- Departed: U59, DRIGGS, ID
- Destination: U42, SALT LAKE CITY, UT
- Flight plan: VFR

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 44; private; airplane ratings: single-engine land; medical: class 3, valid medical--w/ waivers/lim; toxicology performed; flight hours: 100 total

## Weather

- Conditions: Visual (VMC), Day
- Wind: 230° at 20 knots, gusting 30
- Visibility: 20 statute miles
- Lowest ceiling: none
- Temperature: 88 °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 19910714027399A](https://openairdocs.org/incident/19910714027399A), Jul 14, 1991: Piper PA28140, Driggs, ID, Destroyed, 2 fatal. Heavy load,hot,and high density altitude with windshear led to crash in narrow mountain pass. Advised of danger.

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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