# NTSB FTW99LA005: Air Tractor AT-502B, N502S, Ringling, OK, October 8, 1998 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: October 8, 1998, 17:30 local (22:30 UTC) - Place: Ringling, OK - Coordinates: 34.169033, -97.589576 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=34.1690&lon=-97.5896&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report December 1, 1999 - Report: Approved by Office Director - NTSB case key (mKey): 44159 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW99LA005 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/44159/pdf - Page: https://openairdocs.org/ntsb/FTW99LA005 ## Probable cause The pilot's failure to maintain obstacle clearance. A factor was the sun glare which impaired the pilot's vision. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight collision with object, maneuvering - aerial application - light condition - sunglare (contributing factor) - physical impairment(visual deficiency), pilot in command (contributing factor) - object - wire,static - object - pole - clearance - not maintained, pilot in command (cause) - Forced landing, emergency descent/landing ## Analysis The agricultural airplane collided with poles and wires of a power line while applying chemical to a wheat field. At the time of the collision, the airplane was heading west, and the sun 'obstructed' the pilot's vision. Following the collision, which damaged the airplane's rudder, left flap, left spray boom, and fuselage, the pilot landed the airplane in a pasture approximately one mile north of the field. ## Factual narrative On October 8, 1998, approximately 1730 central daylight time, an Air Tractor AT-502B agricultural airplane, N502S, registered to a private individual and operated by Superior Ag-Air of Byers, Texas, collided with a power line while maneuvering near Ringling, Oklahoma. The airplane sustained substantial damage, and the commercial pilot, sole occupant of the aircraft, was not injured. Visual meteorological conditions prevailed and no flight plan was filed for the Title 14 CFR Part 137 aerial application flight. The flight originated from the Perry Municipal Airport, Perry, Oklahoma, approximately 1615, and the intended destination was Byers. The pilot reported that he was spraying a 20 acre wheat field with a double pole power line crossing the middle of the field. As he made a pass toward the west, the sun "obstructed" his vision, and he collided with a pair of poles and wires of the power line. The pilot landed the airplane in a pasture approximately one mile north of the field. Examination of the airplane by an FAA inspector revealed that there was a hole in the upper left side of the fuselage, the inboard portion of the left flap was bent upward, the left spray boom was partially separated, and the upper half of the rudder was torn off. The inspector located the separated portion of the rudder in the field that the airplane had been spraying. He reported that a power line ran diagonally across the north part of the field from northwest to southeast and was supported by pairs of poles approximately 60 feet tall. The upper crosspiece was separated from one pair of poles and lying on the power transmission wires, and the upper static wire was severed. ## Aircraft - Registration: [N502S](https://openairdocs.org/deregistered/N502S-2020-01-30), registration cancelled 2020-01-30, S/N 502B-0456, built 1997 (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-0456 - Airframe hours: 465 - Engines: P&W PT6A-34AG 750 horsepower turbo prop - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: Superior Ag-Air, Inc. - Registered owner: Larry T. Neal - Airworthiness certificate: Special, Restricted (Special) - Last inspection: 100 hour, September 15, 1998, 20 hours before - Departed: F22, PERRY, OK - Destination: BYERS, TX ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 42; commercial; airplane ratings: single-engine land; medical: class 2, valid medical--no waivers/lim.; seat: center; flight hours: 8,000 total, 2,500 in this make and model, 150 in the last 90 days, 50 in the last 30 days, 10 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 140° at 7 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 77 °F, dew point 46 °F - Altimeter: 30.00 inHg - Observed at: LAW, 45 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 19981008028659A](https://openairdocs.org/incident/19981008028659A), Oct 8, 1998: Airtrc AT502B, Ringling, OK, Substantial damage. Acft was involved in aerial application and had pulled up after dusting a field when the sun got in the pilots eyes and the acft struck a utility pole.(.19) on… ## Other investigations on N502S (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 CEN18LA249](https://openairdocs.org/ntsb/CEN18LA249), Jun 28, 2018: Air Tractor AT502 (N502S), Tappen, ND, substantial damage. Probable cause: The partial loss of engine power for reasons that could not be determined based on the available evidence. 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.