# NTSB SEA94LA107: Rich RV-4, N3344E, Weston, ID, April 23, 1994 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: April 23, 1994, 10:00 local (16:00 UTC) - Place: Weston, ID - Coordinates: 42.049365, -112.000679 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=42.0494&lon=-112.0007&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report December 2, 1994 - Report: Approved by Office Director - NTSB case key (mKey): 41914 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA94LA107 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/41914/pdf - Page: https://openairdocs.org/ntsb/SEA94LA107 ## Probable cause THE PILOT'S FAILURE TO USE CARBURETOR HEAT. FACTORS INCLUDE CARBURETOR ICING CONDITIONS, AND NO SUITABLE SITE FOR A FORCED LANDING. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(total) - nonmechanical, maneuvering - weather condition - carburetor icing conditions (contributing factor) - fuel system,carburetor - ice - carburetor heat - not selected, pilot in command (cause) - Forced landing, descent - emergency - On ground/water encounter with terrain/water, landing - flare/touchdown - terrain condition - none suitable (contributing factor) ## Analysis WHILE MANEUVERING IN SERIOUS ICING ATMOSPHERIC CONDITIONS, THE FUEL/AIR FLOW IN THE THROTTLE BODY INJECTOR BECAME RESTRICTED BY ICE BUILD-UP, AND THE ENGINE LOST POWER. THE PILOT SWITCHED FUEL TANKS, TURNED ON THE AUXILIARY FUEL PUMP, AND CYCLED THE IGNITION/MAGNETO SWITCH, BUT DID NOT APPLY CARBURETOR HEAT. BEING UNABLE TO RESTART THE ENGINE, THE PILOT ATTEMPTED A FORCED LANDING ON THE UNSUITABLE TERRAIN. ## Factual narrative On April 23, 1994, approximately 1000 mountain daylight time (MDT), a Rich RV-4 experimental aircraft, N3344E, impacted the terrain during a forced landing about five miles southwest of Weston, Idaho. The forced landing was initiated by the pilot after a loss of engine power while maneuvering at about 1000 feet above the ground. The personal pleasure flight, which departed Logan-Cache Airport, Logan, Utah, about 0945 MDT, was being operated in visual meteorological conditions at the time of the accident. The private pilot, who was the sole occupant, was not injured, but the aircraft sustained substantial damage. No flight plan had been filed, and there was no report of an ELT activation. According to the pilot, while he was circling the town of Weston, the engine began to sputter and then lost power. He switched to the other fuel tank, turned on the auxiliary fuel pump, and cycled the ignition/magneto switch, but did not apply carburetor heat. When the engine would not restart, he elected to attempt a forced landing in a nearby field. When he got closer to the field, the pilot discovered that there was a sprinkler system wheel line across the field, and as he attempted to avoid this line during the landing flare, the right wing of the aircraft impacted the ground. At the time of the accident, the weather observation taken at Logan, Utah, about 15 miles southeast of the accident site, showed a temperature of 45 degrees, and a dew point of 39 degrees. The carburetor icing chart obtained from DOT/FAA/CT- 82/44 shows that, under these atmospheric conditions, there exists the possibility of "serious" carburetor icing at both glide and cruise power settings. The engine on this aircraft had an Ellison Throttle Body Injector installed in place of its standard carburetor. According to the pilot and the Ellison literature, this installation is susceptible to icing within approximately the same ranges as a standard carburetor, and requires the use of carburetor heat under the same atmospheric conditions. ## Aircraft - Registration: [N3344E](https://openairdocs.org/deregistered/N3344E-2013-09-19), registration cancelled 2013-09-19, S/N 2454, built 1993 (OpenAirDocs) - Reported make and model: RICH RV-4 - Registry model: [Rich Edwin D RV-4](https://openairdocs.org/model/rich-edwin-d-rv-4) (registry code 05622CH) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 2454 - Airframe hours: 83 - Engines: LYCOMING O-320-E2A 150 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Rich, Edwin D. - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Annual, June 30, 1993, 83 hours before - Departed: LGU, LOGAN, UT ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 45; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: front; flight hours: 922 total, 83 in this make and model, 870 as pilot in command, 14 in the last 90 days, 5 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 25 statute miles - Lowest ceiling: none - Temperature: 45 °F - Altimeter: 29.00 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 19940423014279A](https://openairdocs.org/incident/19940423014279A), Apr 23, 1994: Amtr RV4, Westonn, ID, Substantial damage. Lost power circling weston. Crash land trying to avoid sprinkler system. Serious carburetor icing in area. ## Other investigations on N3344E (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 DEN02LA063](https://openairdocs.org/ntsb/DEN02LA063), Jun 30, 2002: Rich RV-4 (N3344E), Grand Junction, CO, destroyed, 1 fatal. Probable cause: the pilot failing to maintain aircraft control during the pull up maneuver. A factor relating to the accident was the inadvertent stall spin. 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.