# NTSB SEA90LA178: Cessna 170A, N9157A, Elk Mountain, WY, September 10, 1990

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Limited investigation · Final report
- Date: September 10, 1990, 08:10 local (14:10 UTC)
- Place: Elk Mountain, WY
- Coordinates: 41.680278, -106.409461 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=41.6803&lon=-106.4095&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 2 serious
- Status: Completed, report November 9, 1992
- Report: Approved by Office Director
- NTSB case key (mKey): 41273
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA90LA178
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/41273/pdf
- Page: https://openairdocs.org/ntsb/SEA90LA178

## Probable cause

THE PILOT'S FAILURE TO MAINTAIN FLYING SPEED WHILE AT AN ALTITUDE THAT DID NOT PROVIDE ADEQUATE TERRAIN CLEARANCE FOR A SAFE STALL RECOVERY.

## Sequence of events

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

- Loss of control - in flight, maneuvering
  - stall - inadvertent, pilot in command (cause)
  - airspeed - not maintained, pilot in command (cause)
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

A WITNESS OBSERVED THE CESSNA 170A MAKE A LOW PASS OVER HIM. HE SAID IT STALLED AND ENTERED A NOSE-DOWN ATTITUDE WITH THE WINGS WAGGING. HE SAID THAT THE AIRPLANE HAD LEVELED JUST BEFORE IMPACT. THE AIRCRAFT WAS DESTROYED BY GROUND IMPACT AND THE TWO OCCUPANTS SUSTAINED SERIOUS INJURIES.

## Aircraft

- Registration: [N9157A](https://openairdocs.org/deregistered/N9157A-1999-02-01), registration cancelled 1999-02-01, S/N 18918 (OpenAirDocs)
- Reported make and model: CESSNA 170A
- Registry model: [Cessna 170A](https://openairdocs.org/model/cessna-170a) (registry code 2072304) (OpenAirDocs)
- Category: Airplane
- Serial number: 18918
- Engines: LYCOMING O-360 180 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Lewis R. Johnson
- Airport: NONE, None

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 51; private; airplane ratings: single-engine land; medical: class 3, expired; flight hours: 994 total, 346 in this make and model, 968 as pilot in command, 37 in the last 90 days, 10 in the last 30 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 60 statute miles
- Lowest ceiling: none
- Temperature: -0 °F, dew point -0 °F
- Observed at: RWL, 28 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 19900910038849A](https://openairdocs.org/incident/19900910038849A), Sep 10, 1990: Cessna 170A, Elk Mountain, WY, Substantial damage. Made low pass over persons on ground. Stalled on pullup then leveled prior impact. Flipped over.

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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