# NTSB WPR12LA356: Rockwell S2R, N8468V, Royal City, WA, August 14, 2012 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: August 14, 2012, 06:20 local (13:20 UTC) - Place: Royal City, WA - Coordinates: 46.883056, -119.569725 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=46.8831&lon=-119.5697&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Defining event: [Initial climb: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report September 12, 2013 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - ADs cited in the narratives: [AD 99-11-02](https://openairdocs.org/ad/99-11-02) (OpenAirDocs) - NTSB case key (mKey): 84656 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR12LA356 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/84656/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=84656 - Page: https://openairdocs.org/ntsb/WPR12LA356 ## Probable cause The loss of engine power due to the separation of the No. 2 cylinder exhaust rocker boss housing, which prevented the exhaust valve from opening. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Engine (reciprocating): recip eng cyl section](https://openairdocs.org/ntsb-findings/01058530): Aircraft › Aircraft power plant · Failure (probable cause); cases with it: [Rockwell International S-2R, 2 cases](https://openairdocs.org/ntsb-findings/01058530/cases.md?model=7630202), [All aircraft, 373 cases](https://openairdocs.org/ntsb-findings/01058530/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Initial climb: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) (defining event); cases with it: [Rockwell International S-2R, 7 cases](https://openairdocs.org/ntsb-events/342/sequence.md?model=7630202), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) - [Emergency descent: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Rockwell International S-2R, 8 cases](https://openairdocs.org/ntsb-events/440/sequence.md?model=7630202), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) - [Landing: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Rockwell International S-2R, 20 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=7630202), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The pilot stated that shortly after taking off for the aerial application flight the engine began to run rough. Because he could not maintain altitude and was concerned about clearing a set of power lines in front of him, the pilot partially dumped the airplane’s aerial application load. After the airplane cleared the power lines, the pilot attempted to land on a road; however, during the touchdown the airplane veered off of the road and into a ditch. A postaccident fire consumed the airplane. A postaccident examination of the engine revealed that the No. 2 cylinder exhaust rocker boss housing had separated from the cylinder, which prevented the cylinder's exhaust valve from opening and resulted in the loss of engine power. Maintenance records revealed that the cylinder had been inspected in accordance with the time interval specified by the applicable Federal Aviation Administration airworthiness directive (AD). The AD specifies a 100-hour recurring inspection requirement; the engine had accumulated 91 hours since its last inspection. ## Factual narrative On August 14, 2012, about 0620 Pacific daylight time, a Rockwell International S-2R, N8468V, was substantially damaged during a forced landing following a loss of engine power after takeoff near Royal City, Washington. The certified commercial pilot received minor injuries. The airplane was registered to Royal Flying Service, Inc., and operated under the provisions of 14 Code of Federal Regulations Part 137. Visual meteorological conditions prevailed at the time of the accident and no flight plan was filed. The local flight originated from a private airstrip about 1 minute prior to the accident. In a statement provided to the National Transportation Safety Board (NTSB) investigator-in-charge (IIC), the pilot reported that just after taking off with 325 gallons of liquid fungicide, he detected a rough running engine. The pilot stated that not being able to maintain altitude and in order to clear a set of wires in front of him, he partially dumped the load, cleared the wires, and then attempted to land on a paved road. After touching down, the airplane veered off of the road and into a ditch, where it caught fire and was consumed. A Federal Aviation Administration (FAA) airworthiness aviation safety inspector performed an onsite inspection of the accident airplane. The inspector reported to the IIC that his inspection revealed that the number 2 cylinder exhaust rocker boss housing had separated from the cylinder, which prevented the exhaust valve on the cylinder from opening, creating the loss of engine power. No other evidence of engine damage or malfunction was noted. The FAA inspector's review of company maintenance records indicated that all required inspections had been complied with, including FAA Airworthiness Directive (AD) 99-11-02, which addresses inspection requirements for the accident airplane's cylinder type. The AD specifies a 100-hour recurring inspection requirement; the engine had accumulated 91 hours since its last inspection. ## Aircraft - Registration: [N8468V](https://openairdocs.org/deregistered/N8468V-2018-02-20), registration cancelled 2018-02-20, S/N 2228R, built 1976 (OpenAirDocs) - Reported make and model: ROCKWELL S2R (NO SERIES) - Registry model: [Rockwell International S-2R](https://openairdocs.org/model/rockwell-international-s-2r) (registry code 7630202) (OpenAirDocs) - Registry engine: [Pratt & Whitney R1340 series](https://openairdocs.org/engine/pratt-whitney-r1340-series) (registry code 52016, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 2228R - Airframe hours: 14304 - Engines: Pratt & Whitney R-1340 600 horsepower reciprocating - Damage: Substantial damage - Fire: On-Ground - Flight: Aerial application, Part 137 - Operator: Royal Flying Service Inc. - Registered owner: Royal Flying Service Inc. - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, January 6, 2012, 91 hours before - Departed: 8WA, Royal City, WA - Destination: 8WA, Royal City, WA - Airport: 8WA, Royal Flying Service airstrip ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 24; injuries: minor; commercial; airplane ratings: single-engine land; medical: class 2, without waivers/limitations; last flight review March 1, 2011; seat: single; flight hours: 907 total, 508 in this make and model, 854 as pilot in command, 211 in the last 90 days, 126 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 73 °F, dew point 36 °F - Altimeter: 29.85 inHg - Observed at: EPH, 28 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 20120814017499A](https://openairdocs.org/incident/20120814017499A), Aug 14, 2012: Rockwell International S-2R, Royal City, WA, Substantial damage. On takeoff, aircraft lost power. Pilot was able to sustain it enough to attempt a landing on the highway. He was unable to land straight and when the aircraft… ## Other investigations on N8468V (3) 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 WPR12CA229](https://openairdocs.org/ntsb/WPR12CA229), May 24, 2012: Rockwell International S-2R (N8468V), Royal City, WA, substantial damage. Probable cause: The pilot’s failure to maintain adequate clearance from an object during an aerial application, which resulted in damage to the landing gear and led to the airplane ground looping during the… - [NTSB SEA03LA101](https://openairdocs.org/ntsb/SEA03LA101), Jun 12, 2003: Rockwell International S-2R (N8468V), Royal City, WA, substantial damage. Probable cause: The pilot's failure to maintain clearance from a 20 foot high post while applying chemicals to an agricultural field, which resulted in impact damage to the right main landing gear, and ultimately to… - [NTSB SEA90LA140](https://openairdocs.org/ntsb/SEA90LA140), Jul 15, 1990: Rockwell S2R (N8468V), Royal City, WA, substantial damage. Probable cause: THE PILOT'S FAILURE TO ENSURE AN ADEQUATE SUPPLY OF FUEL, WHICH RESULTED IN FUEL EXHAUSTION. ## Docket (5 files) The files NTSB released with the investigation on August 2, 2013, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=84656. 4.1 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 3.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40376099&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Weather Data (item 2, .PDF, 269 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40376101&FileExtension=.PDF&FileName=Weather%20Data-Master.PDF - FAA Inspector's Report (item 3, .PDF, 15 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40396682&FileExtension=.PDF&FileName=FAA%20Inspector%27s%20Report-Redacted.PDF - FAA Airworthiness Directive 99-11-02 (item 4, .PDF, 62 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40396679&FileExtension=.PDF&FileName=FAA%20Airworthiness%20Directive%2099-11-02-Master.PDF - Release of Aircraft Wreckage, NTSB Form 6120.15 (item 5, .PDF, 235 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40396681&FileExtension=.PDF&FileName=Release%20of%20Aircraft%20Wreckage,%20NTSB%20Form%206120.15-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.