# NTSB LAX88DVA09: Stephenson U-2, N9192V, Porterville, CA, July 26, 1988

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Final report
- Date: July 25, 1988, 17:25 local (Jul 26, 1988, 00:25 UTC)
- Place: Porterville, CA
- Coordinates: 35.960422, -118.92041 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=35.9604&lon=-118.9204&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 1 serious
- Status: Completed, report December 29, 1989
- Report: Approved by Office Director
- NTSB case key (mKey): 25748
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX88DVA09
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/25748/pdf
- Page: https://openairdocs.org/ntsb/LAX88DVA09

## Sequence of events

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

- Loss of control - in flight, maneuvering
  - airspeed - not maintained, pilot in command (cause)
  - lack of total experience in type of aircraft, pilot in command (contributing factor)
  - stall/spin - inadvertent, pilot in command (cause)
  - remedial action - delayed, pilot in command (cause)
- Loss of engine power(total) - nonmechanical, climb
  - operation with known deficiencies in equipment - attempted, pilot in command (cause)
- Forced landing, descent - emergency
- In flight collision with terrain/water, landing - flare/touchdown
  - terrain condition - high vegetation (contributing factor)

## Analysis

DURING A PLEASURE FLIGHT, WHILE SOARING WITH THE ENGINE AT IDLE, THE FLYING WING MOTOR GLIDER INADVERTENTLY ENTERED A STALL. THE PILOT DID NOT RECOVER FROM THE STALL AND THE AIRPLANE BEGAN TO SPIN. THE PILOT WAS ABLE TO REGAIN CONTROL AT APPROXIMATELY 50 FEET AGL. HE THEN REGAINED ABOUT 200 FEET OF ALTITUDE; HOWEVER, WHEN POWER WAS APPLIED, THE ENGINE DID NOT RESPOND. THE PILOT MADE A FORCED LANDING IN A GRAPE VINEYARD. THE PILOT STATED THAT HE HAD ENGINE PROBLEMS PREVIOUS TO THIS FLIGHT BUT THOUGHT HE HAD RESOLVED THEM.

## Aircraft

- Registration: [N9192V](https://openairdocs.org/deregistered/N9192V-1991-12-18), registration cancelled 1991-12-18, S/N U627 (OpenAirDocs)
- Reported make and model: STEPHENSON U-2
- Registry model: [Stephenson Jeffrey Lynn U 2](https://openairdocs.org/model/stephenson-jeffrey-lynn-u-2) (registry code 05666G9) (OpenAirDocs)
- Category: Ultralight, amateur-built
- Serial number: U-627
- Airframe hours: 8
- Engines: ZENOAH G25B-1 20 horsepower reciprocating
- Damage: Destroyed
- Flight: Personal, Part 91
- Registered owner: Jeffrey Lynn Stephenson
- Airworthiness certificate: Special, Experimental (Special)
- Last inspection: Unknown, May 17, 1988, 8 hours before
- Departed: PTV, PORTERVILLE, CA

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 34; private; airplane ratings: single-engine land; medical: class 2, valid medical--no waivers/lim.; seat: center; flight hours: 237 total, 20 in this make and model, 167 as pilot in command, 20 in the last 90 days, 10 in the last 30 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: 310° at 6 knots
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 100 °F
- Altimeter: 30.00 inHg

## 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 19880725028089A](https://openairdocs.org/incident/19880725028089A), Jul 25, 1988: Amtr U2, Porterville, CA, Substantial damage. Entered spin banking in a thermal. Recovered at low altitude. Unable to start engine. Stalled into a vineyard.

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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