# NTSB LAX97LA131: Zenair 601, N4073T, Penn Valley, CA, March 23, 1997 - Type: NTSB accident investigation - Classification: Accident · Fatal · Limited investigation · Final report - Date: March 23, 1997, 08:49 local (16:49 UTC) - Place: Penn Valley, CA - Coordinates: 39.179035, -121.199897 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=39.1790&lon=-121.1999&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: Fatal - Injuries: 1 fatal - Status: Completed, report January 7, 1998 - Report: Approved by Office Director - NTSB case key (mKey): 29749 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX97LA131 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/29749/pdf - Page: https://openairdocs.org/ntsb/LAX97LA131 ## Probable cause Loss of engine power for undetermined reasons. Factors in the accident were the pilot's lack of recent experience, lack of experience in the type aircraft, and physical impairment due to drugs. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power, cruise - reason for occurrence undetermined (cause) - maintenance,annual inspection - not performed - Forced landing, emergency descent/landing - In flight collision with terrain/water, emergency landing - terrain condition - open field - lack of recent experience, pilot in command (contributing factor) - lack of total experience in type of aircraft, pilot in command (contributing factor) - impairment(drugs), pilot in command (contributing factor) ## Analysis No witnesses observed the aircraft when it impacted terrain in a pasture. A witness who lives about 1 mile from the accident site reported that the aircraft's engine was cutting out as it flew over his location. Another witness, inside his home near the accident site, did not hear the engine at all; he reported hearing only a whoosh and a thump. The pilot purchased the aircraft 7 months prior and this was his first flight in the aircraft. He had not had any checkout, and according to his logbook, had not piloted an aircraft in the previous 4 months. The last maintenance entry in the aircraft logbook was an annual inspection performed 18 months prior. A toxicology analysis performed by the FAA's Civil Aeromedical Institute detected impairing amounts of the drug Diphenhydramine in the pilot's blood and urine. ## Factual narrative On March 23, 1997, at 0849 hours Pacific standard time, an experimental, amateur built, Zenair 601, N4073T, impacted terrain in a pasture near Penn Valley, California. The aircraft was destroyed and the private pilot was fatally injured. Visual meteorological conditions prevailed for the personal flight which departed from Nevada County Airport at Grass Valley, California, about 0830. According to an Federal Aviation Administration (FAA) inspector, a witness who lives about 1 mile from the accident site reported that the aircraft's engine was "cutting out" as the aircraft flew over his location. Another witness, inside his home near the accident site, did not hear the engine at all; he reported hearing only a "whoosh" and a "thump." The pilot purchased the aircraft August 30, 1996. The pilot's son told the FAA inspector that this was his father's first flight in the aircraft and that he had not had any checkout. The previous flight in the pilot's logbook was November 13, 1996. The last maintenance entry in the aircraft logbook was an annual inspection on September 7, 1995. Later entries in the logbook were made by the pilot's son, who was not a certificated mechanic or repairman, after the accident, and do not contain an approval for return to service. A toxicology analysis performed by the FAA's Civil Aeromedical Institute detected the drug Diphenhydramine in the pilot's blood (0.062 ug/ml, ug/g) and urine (0.160 ug/ml, ug/g). ## Aircraft - Registration: [N4073T](https://openairdocs.org/deregistered/N4073T-2017-03-24), registration cancelled 2017-03-24, S/N 1414 (OpenAirDocs) - Reported make and model: Zenair 601 - Registry model: [Boyd Raymond C ZENAIR-601](https://openairdocs.org/model/boyd-raymond-c-zenair-601) (registry code 05625VW) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 1414 - Airframe hours: 55 - Engines: Rotax 912 80 horsepower reciprocating - Damage: Destroyed - Flight: Personal, Part 91 - Registered owner: Michael E. Ralli - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Annual, September 7, 1997 - Departed: O17, GRASS VALLEY, CA ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 46; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: left; toxicology performed; flight hours: 248 total, 1 in this make and model, 173 as pilot in command, 1 in the last 90 days, 1 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 180° at 3 knots - Visibility: 5 statute miles - Lowest ceiling: none - Temperature: 61 °F, dew point 46 °F - Altimeter: 30.00 inHg - Observed at: BAB, 13 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 19970323003469A](https://openairdocs.org/incident/19970323003469A), Mar 23, 1997: Amtr CH601HD, Penn Valley, CA, Destroyed, 1 fatal. Crashed in pasture. No checkout in type. Medical drug in pilots system. 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.