# NTSB LAX91LA321: Piper PA 18-135, N9977Q, Gerlach, NV, July 21, 1991

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: July 21, 1991, 10:00 local (17:00 UTC)
- Place: Gerlach, NV
- Coordinates: 40.859848, -119.319664 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=40.8598&lon=-119.3197&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report May 27, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 27299
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX91LA321
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/27299/pdf
- Page: https://openairdocs.org/ntsb/LAX91LA321

## Probable cause

THE FAILURE OF THE PILOT TO MAINTAIN ADEQUATE TERRAIN CLEARANCE BY THE SELECTION OF AN INAPPROPRIATE CRUISE ALTITUDE RESULTING IN AN IN FLIGHT COLLISION WITH TERRAIN.

## Sequence of events

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

- In flight collision with terrain/water, cruise
  - proper altitude - not selected, pilot in command (cause)
  - clearance - not maintained, pilot in command (cause)

## Analysis

IN BOTH HIS WRITTEN AND VERBAL STATEMENTS THE PILOT SAID THAT HE ENCOUNTERED A 'DOWNDRAFT' WHILE FLYING NEAR GERLACH, NEVADA. THE PILOT STATED THAT THE DOWNDRAFT WAS ENCOUNTERED JUST AS THE AIRCRAFT OVERFLEW A SMALL RIDGE AT LOW ALTITUDE AND HE COULD NOT ARREST THE RATE OF DESCENT PRIOR TO COLLIDING WITH THE GROUND IN THE VALLEY BEYOND. IN HIS WRITTEN REPORT OF THE ACCIDENT, THE PILOT SAID THAT THERE WAS NO MECHANICAL MALFUNCTION OF THE AIRCRAFT. THE CLOSEST WEATHER REPORTING STATION WAS REPORTING WINDS OF LESS THAN FIVE KNOTS. THE PILOT DID NOT INDICATE THAT HIGH WINDS OR OTHER UNUSUAL METEOROLOGICAL CONDITIONS WERE INVOLVED IN THE ACCIDENT CIRCUMSTANCES.

## Aircraft

- Registration: [N9977Q](https://openairdocs.org/aircraft/N9977Q), registered now, S/N 18-3575 (OpenAirDocs)
- Reported make and model: PIPER PA 18-135
- Registry model: [Piper PA-18-135](https://openairdocs.org/model/piper-pa-18-135) (registry code 7101820) (OpenAirDocs)
- Category: Airplane
- Serial number: 18-3575
- Engines: LYCOMING O-320 160 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Gregory Powning
- Registered owner: Gregory Powning
- Last inspection: Unknown, January 2, 2000
- Departed: NV18, RENO, NV

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 42; private; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 3, valid medical--w/ waivers/lim; flight hours: 775 total, 500 in this make and model, 740 as pilot in command, 12 in the last 90 days, 4 in the last 30 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 180° at 4 knots
- Visibility: 30 statute miles
- Lowest ceiling: none

## 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 19910721029119A](https://openairdocs.org/incident/19910721029119A), Jul 21, 1991: Piper PA18135, Gerlach, NV, Substantial damage. Flying below ridge reported strong downdraft caused a collision with ground.

## Other investigations on N9977Q (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 SEA90LA055](https://openairdocs.org/ntsb/SEA90LA055), Mar 23, 1990: Piper PA18-160 (N9977Q), Reno, NV, substantial damage. Probable cause: THE PILOT FAILED TO MAINTAIN DIRECTIONAL CONTROL DURING LANDING ROLL.

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.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.