# NTSB CEN11CA287: Air Tractor AT503, N503AD, Telephone, TX, April 13, 2011 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Data collection · Final report - Date: April 13, 2011, 13:00 local (18:00 UTC) - Place: Telephone, TX - Coordinates: 33.840557, -96.01889 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=33.8406&lon=-96.0189&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering-low-alt flying: Aerodynamic stall/spin](https://openairdocs.org/ntsb-events/241) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report August 30, 2011 - Report: Approved by Office Director - NTSB office: Central Region - Parties: FAA Dallas FSDO - NTSB case key (mKey): 78875 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN11CA287 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/78875/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=78875 - Page: https://openairdocs.org/ntsb/CEN11CA287 ## Probable cause The pilot's failure to maintain adequate airspeed which resulted in an aerodynamic stall. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Performance/control parameters: airspeed](https://openairdocs.org/ntsb-findings/01062010): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Air Tractor AT-503A, 1 case](https://openairdocs.org/ntsb-findings/01062010/cases.md?model=0390304), [All aircraft, 1,681 cases](https://openairdocs.org/ntsb-findings/01062010/cases.md) - [Action: lack of action](https://openairdocs.org/ntsb-findings/02041030): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Air Tractor AT-503A, 1 case](https://openairdocs.org/ntsb-findings/02041030/cases.md?model=0390304), [All aircraft, 792 cases](https://openairdocs.org/ntsb-findings/02041030/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Maneuvering-low-alt flying: Aerodynamic stall/spin](https://openairdocs.org/ntsb-events/241) (defining event); cases with it: [Air Tractor AT-503A, 1 case](https://openairdocs.org/ntsb-events/241/sequence.md?model=0390304), [All aircraft, 1,529 cases](https://openairdocs.org/ntsb-events/241/sequence.md) - [Uncontrolled descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Air Tractor AT-503A, 1 case](https://openairdocs.org/ntsb-events/470/sequence.md?model=0390304), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) - [Post-impact: Part(s) separation from AC](https://openairdocs.org/ntsb-events/338); cases with it: [Air Tractor AT-503A, 1 case](https://openairdocs.org/ntsb-events/338/sequence.md?model=0390304), [All aircraft, 563 cases](https://openairdocs.org/ntsb-events/338/sequence.md) ## Analysis The pilot reported that he was maneuvering the airplane at a low altitude on an agricultural application flight when the left wing stalled, the nose dropped, and the airplane descended to the ground. The airplane impacted trees and terrain, and came to rest upright about 450 feet from the initial impact location. There was substantial damage to the fuselage, wings, tail surfaces and all control surfaces. The pilot reported no preimpact mechanical anomalies with the airplane. ## Factual narrative The pilot reported he was maneuvering at low altitude on an agricultural application flight when the left wing stalled, the nose dropped, and the airplane descended out of control. The airplane then impacted trees and terrain, and came to rest upright about 450 feet from the initial impact location. There was substantial damage to the fuselage, wings, tail surfaces and all control surfaces. The pilot reported no preimpact mechanical anomalies with the airplane. ## Aircraft - Registration: [N503AD](https://openairdocs.org/deregistered/N503AD-2013-09-26), registration cancelled 2013-09-26, S/N 503A-0147, built 1991 (OpenAirDocs) - Reported make and model: AIR TRACTOR AT503 (A) - Registry model: [Air Tractor AT-503A](https://openairdocs.org/model/air-tractor-at-503a) (registry code 0390304) (OpenAirDocs) - Registry engine: [Pratt & Whitney PT6A series](https://openairdocs.org/engine/pratt-whitney-pt6a-series) (registry code 52032, turbo-prop) (OpenAirDocs) - Category: Airplane - Serial number: 503A-017 - Engines: PRATT AND WHITNEY PT6A 750 horsepower turbo prop - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: McCRAW MATERIALS LLC - Registered owner: Divlend Equipment Leasing LLC - Airworthiness certificate: Special, Restricted (Special) - Departed: Telephone, TX - Destination: Telephone, TX ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 52; injuries: minor; commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2, with waivers/limitations; last flight review March 9, 2010; seat: front; flight hours: 987 total, 176 in this make and model, 8 in the last 90 days ## Weather - Conditions: Visual (VMC), Day - Wind: 170° at 14 knots, gusting 20 - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 79 °F, dew point 46 °F - Altimeter: 29.98 inHg - Observed at: KDUA, 21 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 20110413006719A](https://openairdocs.org/incident/20110413006719A), Apr 13, 2011: Air Tractor Inc AT-503A, Telephone, TX, Destroyed. Aircraft departed local Private Strip for 2nd flight of the day. Aircraft crashed into wooded area after takeoff. On scene investigation by ASI determined the… ## Docket (2 files) The files NTSB released with the investigation on June 29, 2011, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=78875. 580 KB in all. - Summary of FAA Interviews with the Operator and with the Pilot (item 1, .PDF, 34 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40349851&FileExtension=.PDF&FileName=Summary%20of%20FAA%20Interviews%20with%20the%20Operator%20and%20with%20the%20Pilot-Master.PDF - Maps of Accident Location - (FAA Maps with handwritten margin notations from the pilot or operator) (item 2, .PDF, 546 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40349852&FileExtension=.PDF&FileName=Maps%20of%20Accident%20Location%20-%20(FAA%20Maps%20with%20handwritten%20margin%20notations%20from%20the%20pilot%20or%20operator)-Master.PDF 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.