# NTSB FTW91FA109: North American NA1, N91108, Mountain Home, AR, June 28, 1991

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Field investigation · Final report
- Date: June 28, 1991, 10:50 local (15:50 UTC)
- Place: Mountain Home, AR
- Coordinates: 36.330047, -92.370529 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=36.3300&lon=-92.3705&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 3 serious
- Status: Completed, report March 24, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 23268
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW91FA109
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/23268/pdf
- Page: https://openairdocs.org/ntsb/FTW91FA109

## Probable cause

THE CONTAMINATION OF THE AIRPLANE'S FUEL SYSTEM AND THE FOREIGN OBJECT BLOCKAGE OF THE VAPOR RETURN ORIFICE WHICH INDUCED THE POWER LOSS. A FACTOR WAS THE LACK OF SUITABLE TERRAIN.

## Sequence of events

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

- Loss of engine power(partial) - nonmechanical, takeoff - initial climb
  - fuel system,vapor return system - blocked(total) (cause)
  - fuel system,vapor return system - foreign object (cause)
  - ignition system,magneto - failure,partial
  - fuel system - contamination (cause)
- Forced landing, descent - emergency
- In flight collision with object, descent - emergency
  - object - tree(s)
  - terrain condition - none suitable (contributing factor)

## Analysis

THE PILOT EXPERIENCED A POWER LOSS SHORTLY AFTER TAKEOFF AND SUBSEQUENTLY EXECUTED A FORCED LANDING IN TREES. THERE WERE NO OTHER SUITABLE FORCED LANDING AREAS. THE OCCUPANTS COULD NOT OPEN THE SLIDING CANOPY AND HAD TO EXIT THROUGH THE WINDSHIELD. THE AIRCRAFT WAS THEN DESTROYED BY A POST CRASH FIRE. NEITHER THE PILOT NOR THE PASSENGERS COULD SAY WHETHER OR NOT THE ENGINE HAD COMPLETELY QUIT. INVESTIGATION REVEALED CONTAMINATION IN THE FORM OF GRIT AND LINT THROUGHOUT THE FUEL DELIVERY SYSTEM. IN ADDITION, IT WAS DETERMINED THAT THE FOREIGN MATERIAL HAD BLOCKED THE VAPOR RETURN ORIFICE IN THE CARBURETOR. THE SOURCE OF THE CONTAMINATION WAS NOT DETERMINED; HOWEVER, IT WAS NOT GENERIC TO THE CARBURETOR OR FUEL SYSTEM. IT WAS ALSO DETERMINED THAT THE AIRPLANE WAS BEING OPERATED WITH EXCESSIVE MAGNETO DROP ON BOTH MAGNETOS.

## Aircraft

- Registration: [N91108](https://openairdocs.org/deregistered/N91108-2002-02-08), registration cancelled 2002-02-08, S/N NAV-4-11, built 1946 (OpenAirDocs)
- Reported make and model: NORTH AMERICAN NA1
- Registry model: [North American NAVION](https://openairdocs.org/model/north-american-navion) (registry code 6150130) (OpenAirDocs)
- Registry engine: [Continental E185 series](https://openairdocs.org/engine/continental-e185-series) (registry code 17014, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: NAV4-11
- Airframe hours: 1823
- Engines: CONTINENTAL E-225 225 horsepower reciprocating
- Damage: Destroyed
- Fire: On-Ground
- Flight: Personal, Part 91
- Operator: Diane H. Mullins
- Registered owner: Diane H. Mullins
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, May 1, 1991, 40 hours before
- Destination: HSV, HUNTSVILLE, AL
- Flight plan: VFR
- Airport: 2M9, Baxter County, runway 23, 4,510 × 75 ft, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 37; commercial, flight instructor; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--w/ waivers/lim; seat: left; flight hours: 1,216 total, 70 in this make and model, 1,166 as pilot in command, 150 in the last 90 days, 50 in the last 30 days, 8 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 150° at 10 knots
- Visibility: 11 statute miles
- Lowest ceiling: none
- Temperature: 79 °F, dew point 68 °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 19910628024869A](https://openairdocs.org/incident/19910628024869A), Jun 28, 1991: Tmpson NAVION*, Mountain Home, AR, Destroyed. Lost power on climbout. Landed in trees and burned. Carburetor vent line clogged by debris. Magneto drop excessive.

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.