# NTSB LAX00LA271: Air Tractor AT-401, N4508Y, Ripley, CA, July 13, 2000 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: July 13, 2000, 07:15 local (14:15 UTC) - Place: Ripley, CA - Coordinates: 33.750331, -114.510589 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=33.7503&lon=-114.5106&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report October 9, 2001 - Report: Approved by Office Director - NTSB case key (mKey): 49781 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX00LA271 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/49781/pdf - Page: https://openairdocs.org/ntsb/LAX00LA271 ## Probable cause A loss of engine power due to the separation of a connecting rod from the crankshaft. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(partial) - mech failure/malf, maneuvering - aerial application - engine assembly,connecting rod - separation (cause) - Forced landing, emergency descent/landing - On ground/water encounter with terrain/water, landing - roll - terrain condition - none suitable - terrain condition - berm ## Analysis A partial loss of engine power was experienced during an aerial application flight. During the pilot's attempted forced landing in a cotton field, the airplane collided with a dirt berm and nosed over. An examination of the engine revealed that the connecting rod associated with the No. 7 cylinder had separated from the crankshaft. The connecting rod pieces were severely peened and damaged, and the mode of separation could not be determined. No other evidence of any preexisting failures or malfunctions was noted. The airplane engine's total time was 5,267 hours. It had been operated for 475 hours since receiving its last major overhaul. ## Factual narrative On July 13, 2000, about 0715 hours Pacific daylight time, an Air Tractor AT-401, N4508Y, operated by Farmers Aerial Service, Inc., Blythe, California, experienced a partial loss of engine power during an aerial application flight near Ripley, California. Unable to maintain altitude, the pilot made a forced landing in a cotton field. During rollout, the airplane collided with an irrigation canal soil embankment and nosed over. The airplane was substantially damaged, and the commercial certificated pilot was not injured. Visual meteorological conditions prevailed during the flight that was performed under 14 CFR Part 137. The flight originated from Blythe about 0700. Under the supervision of a Federal Aviation Administration airworthiness inspector, the engine was partially torn down and examined. The inspector reported finding the connecting rod associated with the No. 7 cylinder severed at its midpoint location. Also, the rod had separated from the crankshaft. The inspector indicated that the rod's separation from the crank precipitated its midpoint break. The connecting rod pieces were severely peened and mechanically damaged. No other evidence of any preexisting failures or malfunctions was noted. The engine's total time was reported at 5,267 hours. It had been operated for 475 hours since receiving its last major overhaul. ## Aircraft - Registration: [N4508Y](https://openairdocs.org/deregistered/N4508Y-2022-11-23), registration cancelled 2022-11-23, S/N 401-0751, built 1990 (OpenAirDocs) - Reported make and model: Air Tractor AT-401 - Registry model: [Air Tractor AT-401](https://openairdocs.org/model/air-tractor-at-401) (registry code 0390204) (OpenAirDocs) - Registry engine: [Pratt & Whitney PT6A series](https://openairdocs.org/engine/pratt-whitney-pt6a-series) (registry code 52034, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 401-0751 - Airframe hours: 5267 - Engines: P&W R-1340-AN1 600 horsepower reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: Farmers Aerial Service, Inc. - Registered owner: Brent K. Carpenter - Airworthiness certificate: Special, Restricted (Special) - Last inspection: 100 hour, May 9, 2000, 76 hours before - Departed: BLH, BLYTHE, CA ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 40; commercial; airplane ratings: single-engine land; medical: class 2, valid medical--no waivers/lim.; seat: center; flight hours: 4,006 total, 41 in this make and model, 3,896 as pilot in command, 150 in the last 90 days, 26 in the last 30 days, 3 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 40 statute miles - Lowest ceiling: 18,000 ft broken - Temperature: 196 °F, dew point 102 °F - Altimeter: 29.00 inHg - Observed at: BLH, 8 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 20000713009709A](https://openairdocs.org/incident/20000713009709A), Jul 13, 2000: Airtrc AT401, Blythe, CA, Substantial damage. (-23) Aircraft departed at approximately 0700, July 14, 2000 from Blythe, CA. Airport on a routine agricultural spraying operation. At approximately 0720 after… ## Other investigations on N4508Y (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 FTW04LA130](https://openairdocs.org/ntsb/FTW04LA130), May 19, 2004: Air Tractor AT-401 (N4508Y), San Angelo, TX, destroyed. Probable cause: The loss of engine power for undetermined reasons. A contributing factor was the soft terrain encountered during the aborted takeoff. 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.