# NTSB LAX91LA107: Questaire Venture, N71T, San Luis Obispo, CA, February 12, 1991

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: February 12, 1991, 15:00 local (23:00 UTC)
- Place: San Luis Obispo, CA
- Location: 35.2662° N, 120.6684° W: Placed by OpenAirDocs: center of San Luis Obispo, CA, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=35.2662&lon=-120.6684&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report January 25, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 27118
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX91LA107
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/27118/pdf
- Page: https://openairdocs.org/ntsb/LAX91LA107

## Probable cause

THE FAILURE OF THE FUEL SYSTEM VENT CHECK VALVE, WHICH RESULTED IN FUEL STARVATION TO THE AIRCRAFT'S ENGINE.

## Sequence of events

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

- Loss of engine power(total) - nonmechanical, takeoff - initial climb
  - fuel system,vent - failure,total (cause)
  - fluid,fuel - starvation (cause)
- Forced landing, descent - emergency
- On ground/water encounter with terrain/water, landing - roll
  - terrain condition - rough/uneven (contributing factor)

## Analysis

THE PILOT WAS PERFORMING THE INITIAL TEST FLIGHT ON HIS HOMEBUILT AIRCRAFT.  AFTER EXECUTING SEVERAL APPROACHES WITHOUT ACTUALLY LANDING THE AIRCRAFT, THE PILOT DECIDED TO MAKE A FINAL APPROACH TO A FULL STOP.  AT APPROXIMATELY 800 FEET AGL, THE AIRCRAFT'S ENGINE EXPERIENCED A TOTAL LOSS OF POWER.  THE PILOT EXECUTED A FORCED LANDING TO A FIELD. EXAMINATION BY THE FAA REVEALED THAT THE AIRCRAFT HAD ADEQUATE FUEL SUPPLY, BUT THE ENGINE FAILED AS A RESULT OF FUEL STARVATION CAUSED BY A MALFUNCTIONING FUEL SYSTEM VENT CHECK VALVE.

## Aircraft

- Registration: [N71T](https://openairdocs.org/deregistered/N71T-2002-12-03), registration cancelled 2002-12-03, S/N 26, built 1991 (OpenAirDocs)
- Reported make and model: QUESTAIRE VENTURE
- Registry model: [Thomas Michael C QUESTAIR VENTURE](https://openairdocs.org/model/thomas-michael-c-questair-venture) (registry code 0561845) (OpenAirDocs)
- Registry engine: [Continental IO-550 series](https://openairdocs.org/engine/continental-io-550-series) (registry code 17042, reciprocating) (OpenAirDocs)
- Category: Airplane, amateur-built
- Serial number: 26
- Engines: CONTINENTAL IO-550 280 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Michael C. Thomas
- Registered owner: Michael C. Thomas
- Last inspection: Unknown, January 2, 2000

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 42; private; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: expired; flight hours: 1,220 total, 1 in this make and model

## Weather

- Conditions: Visual (VMC), Day
- Visibility: 5 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 19910212008149A](https://openairdocs.org/incident/19910212008149A), Feb 12, 1991: Amtrjg QUESTAIR20, San Luis Obispo, CA, Substantial damage. Engine quit on go around on first test flight. Lost fuel pressure due a malfunctioning fuel system vent check valve

## Other investigations on N71T (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 LAX92LA038](https://openairdocs.org/ntsb/LAX92LA038), Nov 2, 1991: Questaire Venture (N71T), San Luis Obispo, CA, substantial damage. Probable cause: THE PILOT'S INABILITY TO CONTROL THE AIRCRAFT DURING THE LANDING ROLL DUE TO A FAILURE OF THE LEFT BRAKE AND NOSE WHEEL STEERING SYSTEMS. THE FAILURE OF THE BRAKE AND STEERING SYSTEMS WAS DUE TO A…

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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