# NTSB LAX97LA257: Fronsman Rotorway Exec, N6323F, Lakeport, CA, July 18, 1997

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: July 18, 1997, 09:30 local (16:30 UTC)
- Place: Lakeport, CA
- Coordinates: 39.039554, -122.930023 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=39.0396&lon=-122.9300&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report July 31, 1998
- Report: Approved by Office Director
- NTSB case key (mKey): 29849
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX97LA257
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/29849/pdf
- Page: https://openairdocs.org/ntsb/LAX97LA257

## Probable cause

an undetermined failure of the oil system (lines or filter), while hovering, which resulted in an engine compartment fire that erupted and subsequently destroyed the helicopter after it was landed.

## Sequence of events

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

- Airframe/component/system failure/malfunction, hover - in ground effect
  - lubricating system - undetermined (cause)
- Fire, standing
  - engine compartment - fire (cause)

## Analysis

The pilot said he was practicing hover operations, when the oil pressure began to decrease. By the time he had landed at his parking ramp, the oil pressure was at zero. As he exited the helicopter, the pilot noticed smoke and flames coming from the right side of the engine compartment. He was unsuccessful in extinguishing the fire with a portable fire extinguisher, and the helicopter was destroyed in the subsequent ground fire. The pilot had completed a condition inspection of the experimental helicopter immediately before the flight.

## Factual narrative

On July 18, 1997, at 0930 hours Pacific daylight time, a homebuilt experimental Fronsman Rotorway Exec helicopter, N6323F, was destroyed by a ground fire following a loss of oil pressure while hovering at the Lakeport, California, airport.  The helicopter was owned and operated by the pilot and was on a local area personal flight.  Visual meteorological conditions prevailed at the time and no flight plan was filed.  The private pilot, the sole occupant, was not injured.  The flight originated about 0915 on the morning of the accident from the Lakeport airport.

In a statement to Federal Aviation Administration inspectors, the pilot said he was practicing hover operations when the oil pressure began to decrease below red line.  By the time the pilot landed at his parking ramp, the oil pressure was at zero.  As he exited the helicopter, the pilot noticed smoke and flames coming from the right side of the engine compartment.  He was unsuccessful in extinguishing the fire with a portable extinguisher and the helicopter was destroyed in the subsequent ground fire.

The pilot completed a condition inspection on the helicopter immediately prior to the flight.

## Aircraft

- Registration: [N6323F](https://openairdocs.org/deregistered/N6323F-1997-09-23), registration cancelled 1997-09-23, S/N 3234 (OpenAirDocs)
- Reported make and model: Fronsman ROTORWAY EXEC (ROTORWAY E)
- Registry model: [Fronsman Nathan F ROTORWAY EXEC](https://openairdocs.org/model/fronsman-nathan-f-rotorway-exec) (registry code 13017KB) (OpenAirDocs)
- Category: Helicopter, amateur-built
- Serial number: 3237
- Airframe hours: 150
- Engines: Rotorway RW152 152 horsepower reciprocating
- Damage: Destroyed
- Fire: On-Ground
- Flight: Personal, Part 91
- Registered owner: Nathan F. Fronsman
- Airworthiness certificate: Special, Experimental (Special)
- Last inspection: Annual, July 18, 1997, 1 hours before
- Departed: 102
- Airport: 1O2, Lampson Field

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 58; private; airplane ratings: single-engine land; medical: class 3, valid medical--w/ waivers/lim; seat: right; flight hours: 225 total, 150 in this make and model, 8 in the last 90 days, 8 in the last 30 days, 2 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 20 statute miles
- Lowest ceiling: none
- Temperature: 68 °F, dew point 52 °F
- Altimeter: 29.00 inHg
- Observed at: UKI, 35 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 19970718047599A](https://openairdocs.org/incident/19970718047599A), Jul 18, 1997: Amtr ROTORWAYEXEC, Lakeport, CA, Destroyed. (-16) Nathan fronsman, builder and pilot of this experimental rotorway exec helicopter, reported that during hover practice over the taxiway, he noticed his…

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.