# NTSB WPR10LA247: Ayres S2R, N29254, Glenn, CA, May 18, 2010 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: May 18, 2010, 16:30 local (23:30 UTC) - Place: Glenn, CA - Coordinates: 39.623332, -122.036666 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=39.6233&lon=-122.0367&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering-low-alt flying: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report October 4, 2012 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 76050 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR10LA247 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/76050/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=76050 - Page: https://openairdocs.org/ntsb/WPR10LA247 ## Probable cause Loss of engine power for reasons that could not be determined because postaccident examination of the airframe and engine did not reveal any anomalies that would have precluded normal operation. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Not determined](https://openairdocs.org/ntsb-findings/05000000): Not determined › Not determined · Unknown/Not determined (probable cause); cases with it: [Ayres S-2R, 1 case](https://openairdocs.org/ntsb-findings/05000000/cases.md?model=0970101), [All aircraft, 2,247 cases](https://openairdocs.org/ntsb-findings/05000000/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: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) (defining event); cases with it: [Ayres S-2R, 1 case](https://openairdocs.org/ntsb-events/341/sequence.md?model=0970101), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md) - [Emergency descent: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Ayres S-2R, 2 cases](https://openairdocs.org/ntsb-events/440/sequence.md?model=0970101), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) - [Landing-flare/touchdown: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Ayres S-2R, 3 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=0970101), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis While on approach to spray a field, the pilot observed smoke emanating from the engine compartment. He set up for an emergency landing to a road. During the landing roll, the airplane veered off the road and struck power poles. During a postaccident examination of the engine, no mechanical anomalies were found that would have precluded normal operation. The manufacturer noted that the overall condition of the engine exhibited corrosion and heat erosion. The fuel nozzles were covered in a soot and soil combination. When flow tested, the fuel nozzles exceeded the parameters in the component maintenance manual test procedures. The manufacturer stated that the out-of-limit condition may cause hot-section deterioration over time but would not have prevented normal engine operation. The compressor turbine guide vane ring was examined, and blade fractures from overstress were found, along with chipping and flaking of the coating adjacent to the fracture surfaces. ## Factual narrative On May 18, 2010, at 1630 Pacific daylight time, an Ayres Corporation S2R, N29254, experienced a loss of engine power while maneuvering to spray a field, and struck power poles while attempting a forced landing near Glenn, California. Alaska Air Service, LLC., operated the airplane under the provisions of Title 14 Code of Federal Regulations Part 137 as an aerial application flight. The commercial pilot, the sole occupant, was not injured; the airplane sustained substantial damage to the fuselage and wings. Visual meteorological conditions prevailed for the local area flight, and no flight plan had been filed. According to the pilot, he was on his second spraying run to the field when smoke started to emanate from the engine compartment, and then the engine "rolled down." He chose an adjacent road to make the emergency landing, and began making S-turns to line-up with the road while he lowered the flaps. He crossed power lines in a slight left turn, and touched down on the pavement. He could not prevent the airplane from turning left, and it impacted power poles; the landing gear was sheared off. It came to rest between the road and an orchard. The engine was examined by Pratt & Whitney Canada (PWC) personnel under the supervision of the Federal Aviation Administration. The complete examination report is part of the public docket. They discovered no anomalies that would have precluded normal operation. It was noted that both the large and small exit ducts exhibited discoloration, and heat erosion to the inner dome area, as well as some localized burning. The visual inspection of the fuel control unit exhibited soiling of the body, along with visible surface corrosion on the exposed steel components. PWC personnel also noted bearing grease depletion on the driveshaft bearing plate. During the inspection of the fuel nozzles, PWC personnel found that the nozzle tips were soot and soil coated, with surface corrosion evident; the number 8 inlet adapter was wet. Tab washers were present at each nozzle tip. PWC personnel tested the nozzles in accordance with test record sheet TR2010 Rev. 04 (engine overhaul manual 3011403 Rev. 23). It was noted that all of the fuel nozzles were out of limits. PWC stated that the observations noted during the test may cause hot-section deterioration over time, but would not prevent normal operation of the engine. A fuel sample from the accident airplane was collected during the engine teardown by the engine manufacturer. The exact type of fuel was not known but the presence of an off-road/agricultural use #2 diesel fuel was suspected due to the red color of the sample. The sample was sent to an independent, third party laboratory for analysis. The sample was tested in accordance to ASTM D2887- Standard Test Method for Boiling Range Distribution of Petroleum Fractions by Gas Chromatography. It was determined that sample was a mixture of Jet “A” and off-road #2 diesel fuel. The third party laboratory report including thechart of known fuels boiling point fraction is contained in the public docket. An inspection of the Compressor Turbine (CT) Guide Vane Ring exhibited damage and erosion. The CT was shipped to the National Transportation Safety Board Materials Laboratory for further examination. The NTSB Materials Laboratory complete report is part of the public docket. The longer fractured blades displayed similar characteristics with oxidized fractures showing overstress features and chipping and flaking of the coating adjacent to the fractures. Many of the blades also contained trailing edge impacts and fractures. The leading edges of all blades had varying amounts of previously molten metal spatter on the surfaces. On blade 4, spattered metal was visible on the leading edge up to the fracture, but not onto the fracture, indicating spatter deposition prior to blade fracturing. ## Aircraft - Registration: [N29254](https://openairdocs.org/aircraft/N29254), registered now, S/N R1340-008DC (OpenAirDocs) - Reported make and model: AYRES S2R - Registry model: [Ayres S-2R](https://openairdocs.org/model/ayres-s-2r) (registry code 0970101) (OpenAirDocs) - Category: Airplane - Serial number: R1340-008DC - Airframe hours: 8067 - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: Alaska Air Service LLC - Registered owner: Alaska Air Service LLC - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, March 12, 2010, 18 hours before - Departed: PVT, Hamilton City, CA - Destination: PVT, Hamilton City, CA - Airport: PVT, Hamilton City ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 63; injuries: none; commercial; airplane ratings: single-engine land, single-engine sea; instrument ratings: airplane; medical: class 2, with waivers/limitations; last flight review April 29, 2010; seat: front; flight hours: 11,214 total, 585 in this make and model, 10,923 as pilot in command ## Weather - Conditions: Visual (VMC), Day - Wind: variable at 5 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 64 °F, dew point 43 °F - Altimeter: 30.18 inHg - Observed at: RBL, 40 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 20100518033959A](https://openairdocs.org/incident/20100518033959A), May 18, 2010: Ayres Corpo S-2R, Substantial damage. Was appying agent. In level flight at 45 ft. smoke came from engine followed by a grinding noise. Made a forced landing on road. Touched down at about 60… ## Docket (6 files) The files NTSB released with the investigation on August 7, 2012, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=76050. 10.1 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 558 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40330507&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Materials Laboratory 15 - Factual Report 11-088 (item 2, .PDF, 294 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40352332&FileExtension=.PDF&FileName=Materials%20Laboratory%2015%20-%20Factual%20Report%2011-088-Redacted.PDF - Materials Laboratory 15 - Factual Report 11-079 (5 images) (item 3, .PDF, 598 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40352673&FileExtension=.PDF&FileName=Materials%20Laboratory%2015%20-%20Factual%20Report%2011-079%20(5%20images)-Master.PDF - Report from Glenn County Sheriff's Department (item 4, .PDF, 1.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40372778&FileExtension=.PDF&FileName=Report%20from%20Glenn%20County%20Sheriff%27s%20Department-Redacted.PDF - Engine Logbook (excerpt) (item 5, .PDF, 901 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40372707&FileExtension=.PDF&FileName=Engine%20Logbook%20(excerpt)-Redacted.PDF - Engine Inspection Report (PW) (item 6, .PDF, 6.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40372779&FileExtension=.PDF&FileName=Engine%20Inspection%20Report%20(PW)-Redacted.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.