# NTSB LAX91LA204: Ayres S2RT34, N3633Q, Marysville, CA, May 9, 1991 - Type: NTSB accident investigation - Classification: Accident · Fatal · Limited investigation · Final report - Date: May 9, 1991, 08:49 local (15:49 UTC) - Place: Marysville, CA - Coordinates: 39.149333, -121.470542 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=39.1493&lon=-121.4705&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: Fatal - Injuries: 1 fatal, 1 serious - Status: Completed, report July 14, 1993 - Report: Approved by Office Director - NTSB case key (mKey): 27199 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX91LA204 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/27199/pdf - Page: https://openairdocs.org/ntsb/LAX91LA204 ## Probable cause (aircraft 2) THE PILOTS' INADEQUATE VISUAL LOOKOUT FOR OTHER AIR TRAFFIC. ## Probable cause (aircraft 1) THE PILOTS' INADEQUATE VISUAL LOOKOUT FOR OTHER AIR TRAFFIC. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Midair collision, maneuvering - aerial application - light condition - daylight - visual lookout - inadequate, pilot in command (cause) - wing - failure,total - In flight collision with terrain/water, descent - uncontrolled - Midair collision, takeoff - initial climb - light condition - daylight - visual lookout - inadequate, pilot in command (cause) - wing - failure,total - In flight collision with terrain/water, descent - uncontrolled ## Analysis (aircraft 2) THE PILOT OF THE AYRES (THRUSH) WAS PERFORMING AN AERIAL APPLICATION FLIGHT OVER A FIELD ADJACENT TO AN AIRSTRIP FROM WHICH A SCHWEIZER (AG CAT) HAD JUST DEPARTED. THE SCHWEIZER WAS ENROUTE TO PERFORM AN AERIAL APPLICATION FLIGHT AT ANOTHER FIELD. AS THE AYRES PILOT WAS BEGINNING TO REVERSE COURSE TO MAKE ANOTHER APPLICATION RUN, THE SCHWEIZER, WHICH WAS ON INITIAL CLIMB, COMMENCED A RIGHT TURN, AND THE FLIGHT PATHS OF THE TWO AIRPLANES CONVERGED. AFTER THE NEARLY HEAD ON COLLISION, THE TWO AIRPLANES DESCENDED OUT OF CONTROL AND CRASHED INTO THE UNDERLYING FIELD. ## Analysis (aircraft 1) THE PILOT OF THE AYRES (THRUSH) WAS PERFORMING AN AERIAL APPLICATION FLIGHT OVER A FIELD ADJACENT TO AN AIRSTRIP FROM WHICH A SCHWEIZER (AG CAT) HAD JUST DEPARTED. THE SCHWEIZER WAS ENROUTE TO PERFORM AN AERIAL APPLICATION FLIGHT AT ANOTHER FIELD. AS THE AYRES PILOT WAS BEGINNING TO REVERSE COURSE TO MAKE ANOTHER APPLICATION RUN, THE SCHWEIZER, WHICH WAS ON INITIAL CLIMB, COMMENCED A RIGHT TURN, AND THE FLIGHT PATHS OF THE TWO AIRPLANES CONVERGED. AFTER THE NEARLY HEAD ON COLLISION, THE TWO AIRPLANES DESCENDED OUT OF CONTROL AND CRASHED INTO THE UNDERLYING FIELD. ## Aircraft 1 - Registration: N3633Q (not matched to a registry record) - Reported make and model: Ayres S2RT34 - Category: Airplane - Serial number: 60747 - Engines: P&W PT6A-34AG 750 horsepower turbo prop - Damage: Destroyed - Fire: Unknown - Flight: Aerial application, Part 137 - Operator: Bowles Flying Service - Registered owner: Agro West Inc. - Last inspection: Unknown, January 2, 2000 - Departed: NONE, MARYSVILLE, CA ## Aircraft 2 - Registration: N4012Y (not matched to a registry record) - Reported make and model: Schweizer G164B - Category: Airplane - Serial number: 777B - Engines: P&W R1340 600 horsepower reciprocating - Damage: Destroyed - Flight: Aerial application, Part 137 - Operator: Onstott Dusters, Inc. - Registered owner: Onstott Dusters, Inc. - Last inspection: Unknown, January 2, 2000 - Departed: NONE, MARYSVILLE, CA ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot, aircraft N3633Q; age 48; commercial; airplane ratings: single-engine sea, multi-engine sea, single-engine land, multi-engine land; medical: class 2, valid medical--no waivers/lim.; toxicology performed; flight hours: 8,000 total - Pilot, aircraft N4012Y; age 45; commercial; airplane ratings: single-engine land; medical: class 2, valid medical--no waivers/lim.; flight hours: 4,460 total ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 5 statute miles - Lowest ceiling: none ## FAA reports on this event (2) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 19910509014872A](https://openairdocs.org/incident/19910509014872A), May 9, 1991: Scwzer G164B, Marysville, CA, Destroyed. On turning climbout collided head on with N4012Y that was on spray turn around from nearby field. Failed note other - [Accident 19910509014871A](https://openairdocs.org/incident/19910509014871A), May 9, 1991: Ayres S2RT34RESTD, Marysville, CA, Destroyed, 1 fatal. On spray turn around collided head on with N3633Q that was in turn climbout from ag strip. Failed to note other. 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.