# NTSB DFW08LA167: Air Tractor AT-502B, N5005G, Bethany, MO, June 24, 2008 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: June 23, 2008, 19:10 local (Jun 24, 2008, 00:10 UTC) - Place: Bethany, MO - Coordinates: 40.276668, -94.007225 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=40.2767&lon=-94.0072&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Defining event: [Takeoff: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report May 12, 2009 - Report: Approved by Office Director - Parties: FAA FSDO, Pratt & Whitney Canada, Transportation Safety Board of Canada - NTSB case key (mKey): 68303 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DFW08LA167 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/68303/pdf - Page: https://openairdocs.org/ntsb/DFW08LA167 ## Probable cause The pilot's decision to take off with a known deficiency. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Info processing/decision: decision making/judgment](https://openairdocs.org/ntsb-findings/02041520): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Air Tractor AT-502B, 15 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md?model=0390307), [All aircraft, 3,098 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md) - [Engine (turbine/turboprop)](https://openairdocs.org/ntsb-findings/01057200): Aircraft › Aircraft power plant · Failure; cases with it: [Air Tractor AT-502B, 3 cases](https://openairdocs.org/ntsb-findings/01057200/cases.md?model=0390307), [All aircraft, 67 cases](https://openairdocs.org/ntsb-findings/01057200/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Takeoff: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) (defining event); cases with it: [Air Tractor AT-502B, 7 cases](https://openairdocs.org/ntsb-events/342/sequence.md?model=0390307), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) - [Takeoff: Loss of control in flight](https://openairdocs.org/ntsb-events/240); cases with it: [Air Tractor AT-502B, 18 cases](https://openairdocs.org/ntsb-events/240/sequence.md?model=0390307), [All aircraft, 5,002 cases](https://openairdocs.org/ntsb-events/240/sequence.md) - [Uncontrolled descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Air Tractor AT-502B, 46 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=0390307), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The pilot stated that another pilot believed the accident airplane's engine was not responding properly, so the commercial pilot decided to fly the airplane. After loading approximately 430 gallons of applicant, the pilot began his takeoff roll. During the takeoff roll, and with 1/4 runway remaining, the engine began "rolling back." The pilot raised the nose of the airplane at the departure end and cleared the airfield fence before settling back to the ground. The airplane continued to travel through a field towards a residence when the engine momentarily regained power. The airplane collided with a garage and a residence, rolled inverted and slid 50 yards. An examination of the engine and fuel control unit (FCU) bellow did not reveal any anomalies. The FCU was impact damaged and could not be tested. Testing failed to determine the reason for the loss of engine power. ## Factual narrative On June 23, 2008, approximately 1910 central daylight time, an Air Tractor AT-502B, N5005G, was substantially damaged upon collision with terrain following a partial loss of power during initial takeoff from Bethany Memorial Airport(75K), Bethany, Missouri. Visual meteorological conditions prevailed at the time of the accident. The aerial application flight was being conducted under the provisions of Title 14 Code of Federal Regulations (CFR) Part 137 without a filght plan. The commercial pilot was not injured. The local flight was originating at the time of the accident. The accident pilot stated that another pilot told him the engine was not responding properly. In order to see how the engine was performing, the accident pilot decided to fly the airplane. After loading approximately 430 gallons of applicant, the pilot began his takeoff roll. At approximately mid-field the airplane's tail wheel raised up, but at approximately 560 feet of runway remaining, the engine began "rolling back." The pilot raised the nose of the airplane at the departure end and cleared the airfield fence before settling back to the ground. The airplane continued to travel through a field towards a residence when the engine momentarily regained power. The airplane collided with a garage and a residence, rolled inverted and slid 50 yard before coming to rest. The engine was removed and shipped to Pratt & Whitney Canada. Under the supervision of the Transportation Safety Board of Canada (TSB), an engine examination revealed that the engine displayed signs of rotation at the time of impact. An examination of the accessories revealed the fuel control unit (FCU) bellows was found with deformation consistent with power reduction and erratic engine performance in the high power range. Furthermore, an adjustment was noted to the FCU lever adjustment indicating possible maintenance corrections for low power. The FCU installed on the engine was found to be impact damaged and could not be tested. An examination conducted on the FCU bellows was conducted by Honeywell under the supervision of the FAA; no anomalies were detected in the FCU bellows. The bellows was returned to Pratt & Whitney Canada and, under the supervision of the TSB, was tested in a "slave" FCU with no anomalies detected. ## Aircraft - Registration: [N5005G](https://openairdocs.org/deregistered/N5005G-2012-08-21), registration cancelled 2012-08-21, S/N 502B-0399, built 1996 (OpenAirDocs) - Reported make and model: AIR TRACTOR AT-502B - Registry model: [Air Tractor AT-502B](https://openairdocs.org/model/air-tractor-at-502b) (registry code 0390307) (OpenAirDocs) - Registry engine: [Pratt & Whitney PT6A series](https://openairdocs.org/engine/pratt-whitney-pt6a-series) (registry code 52034, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 502B-0399 - Airframe hours: 5158 - Engines: Pratt & Whitney Canada PT-6-28 680 horsepower turbo prop - Damage: Substantial damage - Fire: On-Ground - Flight: Aerial application, Part 137 - Operator: Midwest Spray Service, doing business as Midwest Spray Service LLC - Registered owner: Midwest Spray Service - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, March 11, 2008 - Departed: 75K, Bethany, MO - Airport: 75K, Bethany Memorial Airport, runway 03, 2,255 × 48 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 49; injuries: none; commercial, flight instructor; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2, without waivers/limitations; last flight review December 23, 2006; seat: single; flight hours: 8,488 total, 1,250 in this make and model, 8,488 as pilot in command, 210 in the last 90 days, 45 in the last 30 days, 8 in the last 24 hours ## Weather - Conditions: Visual (VMC), Not reported - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 75 °F, dew point 54 °F - Altimeter: 30.09 inHg - Observed at: LWD, 22 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 20080623839829A](https://openairdocs.org/incident/20080623839829A), Jun 23, 2008: Airtrc AT502B, Bethany, MO, Destroyed. (-23) The pilot was taking off on runway 3 at Bethany Memorial Airport (75K), Bethany, MO, with a load of fertilizer to be used for aerial application. During… ## Other investigations on N5005G (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 FTW99LA249](https://openairdocs.org/ntsb/FTW99LA249), Sep 6, 1999: Air Tractor AT-502B (N5005G), Seminole, TX, substantial damage. Probable cause: The pilot's failure to maintain obstacle clearance. 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.