# NTSB SEA91LA154: Jerrell RV-4, N44AZ, Yellowstonepark, WY, July 4, 1991

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Limited investigation · Final report
- Date: July 4, 1991, 09:00 local (15:00 UTC)
- Place: Yellowstonepark, WY
- Coordinates: 44.570365, -110.509788 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=44.5704&lon=-110.5098&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 1 fatal, 1 minor
- Status: Completed, report January 25, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 41469
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA91LA154
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/41469/pdf
- Page: https://openairdocs.org/ntsb/SEA91LA154

## Probable cause

A COLLAPSED INDUCTION AIR DUCT.  FACTORS INCLUDE INADEQUATE DESIGN BY THE MANUFACTURER/BUILDER, AND A MISJUDGED RATE OF DESCENT BY THE PILOT.

## Sequence of events

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

- Loss of engine power(partial) - nonmechanical, cruise
  - induction air ducting - collapsed (cause)
  - acft/equip,inadequate design, manufacturer (contributing factor)
- Forced landing, descent - emergency
  - unsuitable terrain or takeoff/landing/taxi area (contributing factor)
- In flight collision with terrain/water, approach - vfr pattern - final approach
  - proper descent rate - misjudged, pilot in command (contributing factor)

## Analysis

THE PILOT OF THE RV-4 EXPERIMENTAL AIRCRAFT EXPERIENCED A PARTIAL POWER LOSS, AND RECEIVED FATAL INJURIES WHEN THE AIRCRAFT IMPACTED THE WATER, DURING AN ATTEMPTED EMERGENCY LANDING, NEAR THE SHORELINE OF A LAKE. LATER INSPECTION OF THE ENGINE FOUND THAT THE SCAT TUBING WHICH RAN FROM THE AIR INTAKE FILTER TO THE FUEL INJECTOR BODY, WAS ROUTED IN A MANNER THAT CAUSED THE INTERNAL WIRE SUPPORT TO BE DISPLACED, ALLOWING THE TUBING WALLS TO COLLAPSE.  THIS CONDITION REDUCED THE INDUCTION AIRFLOW TO THE ENGINE.

## Aircraft

- Registration: [N44AZ](https://openairdocs.org/deregistered/N44AZ-1996-07-24), registration cancelled 1996-07-24, S/N 1 (OpenAirDocs)
- Reported make and model: JERRELL RV-4
- Registry model: [Jerrell Donald A JERRELL RV-4](https://openairdocs.org/model/jerrell-donald-a-jerrell-rv-4) (registry code 05608LB) (OpenAirDocs)
- Category: Airplane, amateur-built
- Serial number: 1
- Engines: LYCOMING IO-320-E3D 150 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Donald A. Jerrell
- Registered owner: Donald A. Jerrell
- Departed: WYS, WESTYELLOWSTONE, WY
- Destination: CPR, CASPER, WY

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 43; commercial; airplane ratings: multi-engine land, single-engine land; medical: class 2, valid medical--w/ waivers/lim; toxicology performed; flight hours: 450 total

## Weather

- Conditions: Visual (VMC), Day
- Visibility: 20 statute miles
- Lowest ceiling: none
- Temperature: -0 °F, dew point -0 °F

## 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 19910704025719A](https://openairdocs.org/incident/19910704025719A), Jul 4, 1991: Amtrvn VANSRV4, Yellowstone Par, WY, Substantial damage, 1 fatal. Trying to land on shore,lost power, stalled, and impacted shallow lake water. Scat air intake line pinched,collapsed

## Other investigations on N44AZ (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 FTW96FA208](https://openairdocs.org/ntsb/FTW96FA208), May 11, 1996: Jerrell RV-4 (N44AZ), Englewood, CO, destroyed, 1 fatal. Probable cause: failure of the pilot of the RV-4, N44AZ, to comply with an ATC clearance by landing on the wrong runway, and the failure of the pilot of the SU-29, N55SU, to maintain an adequate visual lookout.…

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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