# NTSB CHI91LA138: Piper PA-22-108, N5421Z, Millard, NE, April 23, 1991

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: April 23, 1991, 12:40 local (17:40 UTC)
- Place: Millard, NE
- Coordinates: 41.209411, -96.1203 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=41.2094&lon=-96.1203&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report March 31, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 15050
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI91LA138
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/15050/pdf
- Page: https://openairdocs.org/ntsb/CHI91LA138

## Probable cause

IMPROPER USE OF APU BY UNKNOWN PERSONNEL WHICH RESULTED IN THE AIRPLANE'S ELECTRICAL WIRING MELTING AND SUBSEQUENT SHORT.

## Sequence of events

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

- Fire, cruise
  - electrical system,electric wiring - melted (cause)
  - apu - improper use of, unknown (cause)
  - electrical system,electric wiring - shorted (cause)
- Forced landing, descent - emergency
- Fire, standing

## Analysis

THE PILOT SAID THAT SHORTLY AFTER TAKEOFF, AN ELECTRICAL FIRE ERUPTED UNDER THE PASSENGER'S SEAT.  AN EMERGENCY LANDING WAS MADE WHICH RESULTED IN DAMAGE TO THE AIRPLANE. THE AIRPLANE WAS DESTROYED BY A POST-LANDING FIRE. POST-ACCIDENT INVESTIGATION REVEALED THAT THE AIRPLANE HAD BEEN STARTED WITH A 24 VOLT BOOST INSTEAD OF A 12 VOLT BOOST WHICH RESULTED IN MELTED WIRES AND THE SUBSEQUENT SHORT AND FIRE.

## Aircraft

- Registration: [N5421Z](https://openairdocs.org/deregistered/N5421Z-2013-04-09), registration cancelled 2013-04-09, S/N 22-9194, built 1961 (OpenAirDocs)
- Reported make and model: PIPER PA-22-108
- Registry model: [Piper PA-22-108](https://openairdocs.org/model/piper-pa-22-108) (registry code 7102204) (OpenAirDocs)
- Registry engine: [Lycoming 0-235 series](https://openairdocs.org/engine/lycoming-0-235-series) (registry code 41505, 4 cycle) (OpenAirDocs)
- Category: Airplane
- Serial number: 22-9194
- Airframe hours: 2204
- Engines: LYCOMING O-235-C1B 108 horsepower reciprocating
- Damage: Destroyed
- Fire: Both
- Flight: Personal, Part 91
- Operator: Dale E. Frimodt
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, April 2, 1990
- Departed: MLE, MILLARD, NE

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 44; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: left; flight hours: 146 total, 145 in this make and model, 107 as pilot in command, 4 in the last 90 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: 350° at 14 knots
- Visibility: 15 statute miles
- Lowest ceiling: none
- Temperature: -0 °F, dew point -0 °F
- Observed at: OMA, 10 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 19910423012099A](https://openairdocs.org/incident/19910423012099A), Apr 23, 1991: Piper PA22108, Omaha, NE, Destroyed. Fire erupted under passengers seat made emergency landing safely. Passenger seat had collapsed. Shorted battery box

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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