# NTSB SEA91LA165: Cessna 172N, N734MD, Medford, OR, July 9, 1991

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Limited investigation · Final report
- Date: July 9, 1991, 14:28 local (21:28 UTC)
- Place: Medford, OR
- Coordinates: 42.329555, -122.789115 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=42.3296&lon=-122.7891&mi=10
- Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 1 minor
- Status: Completed, report May 10, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 41477
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA91LA165
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/41477/pdf
- Page: https://openairdocs.org/ntsb/SEA91LA165

## Probable cause

AN INTENTIONAL PORPOISE.  FACTORS INCLUDE THE PILOT'S PSYCHOLOGICAL CONDITION.

## Sequence of events

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

- In flight collision with terrain/water, landing - flare/touchdown
  - sabotage - intentional, pilot in command (cause)
  - porpoise/pilot-induced oscillation - intentional, pilot in command (cause)
  - psychological condition, pilot in command (contributing factor)

## Analysis

THE PILOT OF THE CESSNA 172 CONTACTED THE TOWER APPROXIMATELY EIGHT MINUTES PRIOR TO THE CRASH, AND INDICATED THAT HE WAS HAVING TROUBLE WITH AILERON CONTROL, AND WOULD BE RETURNING TO THE FIELD TO ATTEMPT A LANDING. THE AIRCRAFT TOUCHED DOWN IN A GRASSY AREA NEAR THE RUNWAY, AND THEN BOUNCED BACK INTO THE AIR ABOUT FIVE TIMES BEFORE THE RIGHT WING CONTACTED THE GROUND.  BOTH THE LOCAL POLICE AND THE FAA INVESTIGATED THE POSSIBILITY THAT THE CRASH OF THE AIRCRAFT WAS INTENTIONAL.  AS A RESULT OF THIS ACCIDENT, THE PILOT, WHO WAS UNDER PSYCHOLOGICAL PRESSURE AT THE TIME OF THE FLIGHT, WAS LATER INDICTED BY THE GRAND JURY FOR MALICIOUS DESTRUCTION OF PROPERTY.  PRIOR TO THE INDICTMENT, THE FAA ISSUED AN EMERGENCY REVOCATION OF THE PILOT'S LICENSE.

## Aircraft

- Registration: N734MD (not matched to a registry record)
- Reported make and model: CESSNA 172N
- Category: Airplane
- Serial number: 17268953
- Airframe hours: 4146
- Engines: LYCOMING O-320H2AD 160 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Medford Jet Center
- Registered owner: Medford Jet Center
- Airworthiness certificate: Standard, Utility; Standard, Normal
- Last inspection: Annual, August 31, 1990
- Airport: MFR, Medford

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 23; commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: left; flight hours: 239 total, 43 in this make and model, 183 as pilot in command

## Weather

- Conditions: Visual (VMC), Day
- Wind: 320° at 5 knots
- Visibility: 30 statute miles
- Lowest ceiling: none
- Temperature: 86 °F, dew point 48 °F
- Altimeter: 29.00 inHg
- Observed at: MFR, 1 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 19910709026709A](https://openairdocs.org/incident/19910709026709A), Jul 9, 1991: Cessna 172N, Medford, OR, Substantial damage. Reported aileron control lost. Crash landed on airport. No defects. Pilot was in trouble with police prior flight.

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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