# NTSB FTW95LA301: Air Tractor AT-401, N1004W, Cash, AR, July 11, 1995 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: July 11, 1995, 11:40 local (16:40 UTC) - Place: Cash, AR - Coordinates: 35.790817, -90.929389 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=35.7908&lon=-90.9294&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report November 8, 1995 - Report: Approved by Office Director - NTSB case key (mKey): 19501 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW95LA301 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/19501/pdf - Page: https://openairdocs.org/ntsb/FTW95LA301 ## Probable cause ENGINE POWER LOSS DUE TO PARTIAL FAILURE OF ONE MAGNETO COMBINED WITH TOTAL FAILURE OF THE OTHER MAGNETO. A FACTOR WAS THE LACK OF SUITABLE TERRAIN 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(partial) - mech failure/malf, cruise - normal - ignition system,magneto - failure,partial (cause) - ignition system,magneto - failure,total (cause) - Forced landing, emergency descent/landing - Nose over, emergency landing - terrain condition - none suitable (contributing factor) - terrain condition - crop ## Analysis THE AIRPLANE WAS EN ROUTE TO FERTILIZE A FIELD WHEN THE ENGINE LOST POWER AND BEGAN 'BACKFIRING, MISSING AND SMOKING.' THE PILOT DUMPED HIS LOAD AND ATTEMPTED TO RETURN TO THE DEPARTURE AIRSTRIP. THE ENGINE CONTINUED TO LOSE POWER AND THE PILOT WAS FORCED TO LAND IN A BEAN FIELD. THE AIRPLANE NOSED OVER AND CAME TO REST INVERTED. MAGNETO TESTING REVEALED ONE MAGNETO WAS NOT FIRING DUE TO INTERNAL DRIVE GEAR FAILURE AND THE OTHER MAGNETO WAS MISFIRING DUE TO A 'WIDE' POINT GAP CLEARANCE. ## Factual narrative On July 11, 1995, at 1140 central daylight time, an Air Tractor AT-401, N1004W, nosed over during a forced landing near Cash, Arkansas. The commercial pilot was not injured and the airplane sustained substantial damage. No flight plan was filed for the aerial application flight conducted by Morrison Aircraft Corporation under Title 14 CFR Part 137. Visual meteorological conditions prevailed for the flight which departed a private airstrip near Cash at 1135 CDT. According to the pilot, he was en route to fertilize a field when the engine lost power and began "backfiring, missing and smoking." The pilot dumped the load of Urea and attempted to return to the private airstrip. The engine continued to lose power and the pilot landed in a soybean field. The airplane nosed over and came to rest inverted. Damage included a bent vertical stabilizer and rudder and deformed rear fuselage longerons. The operator arranged to have a certified repair station examine the magnetos. When run on a test stand, one of the magnetos failed to spark. Disassembly revealed that an internal drive gear had failed. The other magneto was tested and failed to spark below 400 rpm and displayed "erratic misfiring" above 400 rpm. The point gap clearance was measured and found to be "too wide causing misfiring at low and high rpm." ## Aircraft - Registration: [N1004W](https://openairdocs.org/deregistered/N1004W-2005-06-22), registration cancelled 2005-06-22, S/N 401-0687, built 1988 (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 R1340 series](https://openairdocs.org/engine/pratt-whitney-r1340-series) (registry code 52016, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 401-0687 - Airframe hours: 2225 - Engines: P&W R-1340-AN-1 600 horsepower reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Registered owner: Morrison Aircraft Corp. - Airworthiness certificate: Special, Restricted (Special) - Last inspection: 100 hour, March 31, 1995, 44 hours before - Departed: NONE ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 34; commercial; airplane ratings: single-engine land; medical: class 2, valid medical--no waivers/lim.; seat: center; flight hours: 361 total, 108 in this make and model, 296 as pilot in command, 132 in the last 90 days, 106 in the last 30 days, 5 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Visibility: 15 statute miles - Lowest ceiling: none - Temperature: 88 °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 19950711018519A](https://openairdocs.org/incident/19950711018519A), Jul 11, 1995: Airtrc AT401, Cash, AR, Substantial damage. En route to spray field engine lost power. Dumped load. Nosed over landing. Both mags misfiring or not firing. ## Other investigations on N1004W (2) 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 FTW96LA251](https://openairdocs.org/ntsb/FTW96LA251), Jun 15, 1996: Air Tractor AT-401 (N1004W), Cash, AR, substantial damage. Probable cause: The partial loss of engine power due to fuel contamination. A factor was the lack of suitable terrain available for the forced landing. - [NTSB MIA91LA219](https://openairdocs.org/ntsb/MIA91LA219), Sep 16, 1991: Air Tractor AT-401 (N1004W), Sumner, MS, substantial damage. Probable cause: FAILURE OF THE NO. 1 CYLINDER ASSEMBLY. 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.