# NTSB WPR13LA308: WSK PZL Mielec M-18B, N7643J, Caldwell, ID, July 3, 2013 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: July 3, 2013, 06:05 local (12:05 UTC) - Place: Caldwell, ID - Coordinates: 43.697498, -116.644447 - Nearby events: https://openairdocs.org/map.md?lat=43.6975&lon=-116.6444&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Defining event: [Takeoff: Miscellaneous/other](https://openairdocs.org/ntsb-events/900) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report March 24, 2014 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Adminstration - NTSB case key (mKey): 87389 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR13LA308 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/87389/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=87389 - Page: https://openairdocs.org/ntsb/WPR13LA308 ## Probable cause The pilot’s improper decision to continue the takeoff with a tailwind after he recognized a performance problem with the airplane and his delayed action to dump the chemical load. ## 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: [WSK PZL Mielec M-18A, 1 case](https://openairdocs.org/ntsb-findings/02041520/cases.md?model=9810103), [All aircraft, 3,098 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md) - [Action: lack of action](https://openairdocs.org/ntsb-findings/02041030): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [WSK PZL Mielec M-18A, 1 case](https://openairdocs.org/ntsb-findings/02041030/cases.md?model=9810103), [All aircraft, 792 cases](https://openairdocs.org/ntsb-findings/02041030/cases.md) - [Wind: tailwind](https://openairdocs.org/ntsb-findings/03034015): Environmental issues › Conditions/weather/phenomena · Contributed to outcome; cases with it: [WSK PZL Mielec M-18A, 2 cases](https://openairdocs.org/ntsb-findings/03034015/cases.md?model=9810103), [All aircraft, 594 cases](https://openairdocs.org/ntsb-findings/03034015/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Takeoff: Preflight or dispatch event](https://openairdocs.org/ntsb-events/030); cases with it: [WSK PZL Mielec M-18A, 2 cases](https://openairdocs.org/ntsb-events/030/sequence.md?model=9810103), [All aircraft, 355 cases](https://openairdocs.org/ntsb-events/030/sequence.md) - [Takeoff: Other weather encounter](https://openairdocs.org/ntsb-events/400); cases with it: [WSK PZL Mielec M-18A, 1 case](https://openairdocs.org/ntsb-events/400/sequence.md?model=9810103), [All aircraft, 1,127 cases](https://openairdocs.org/ntsb-events/400/sequence.md) - [Takeoff: Miscellaneous/other](https://openairdocs.org/ntsb-events/900) (defining event); cases with it: [WSK PZL Mielec M-18A, 1 case](https://openairdocs.org/ntsb-events/900/sequence.md?model=9810103), [All aircraft, 1,556 cases](https://openairdocs.org/ntsb-events/900/sequence.md) ## Analysis The pilot reported that, when he applied power for takeoff on an aerial application flight, the airplane seemed to accelerate normally until the tailwheel lifted off the ground. He adjusted the power lever forward, but the torque did not seem to increase. The pilot stated that, at that point, it was "unlikely" that the airplane would lift off the ground before it reached the end of the runway but that it was "too late to abort" the takeoff. The pilot advanced the power lever full forward and held it there. He then jettisoned the applicant load and simultaneously pulled back on the control stick. The main landing gear wheels lifted off the ground but the tailwheel did not. The airplane subsequently collided with a fence and came to rest in a river. A postaccident examination of the engine revealed no evidence of mechanical failures or malfunctions that would have precluded normal operation. An 8-knot tailwind existed at the time of the takeoff, which most likely resulted in the airplane's performance deficiency. The pilot further reported that "a more prompt recognition of the problem and an earlier decision to dump the load [of applicant] may possibly have prevented the aircraft from hitting the fence." ## Factual narrative On July 3, 2013, about 0605 mountain daylight time, a WSK PZL Mielec M-18B (turbine-powered Dromader), N7643J, was substantially damaged during takeoff at Hubler Field Airport, Caldwell, Idaho. The commercial pilot, the sole occupant on board, was not injured. Valley Air Service, Inc., was operating the airplane under the provisions of 14 Code of Federal Regulations Part 137. Visual meteorological conditions prevailed for the local aerial application flight, which was originating at the time of the accident. A flight plan had not been filed. The pilot stated that this was his first flight for the day, and he had approximately 490 gallons of applicant and 120 gallons of fuel on board. He taxied to the end of runway 29, a 2,800-foot-long runway and applied power for takeoff. The pilot said the airplane appeared to accelerate normally until the tail wheel came up and then the airplane's acceleration did not seem normal. He adjusted the power lever forward a bit, but the torque did not seem to increase. As he reached the end of the runway, he realized that he would not make it off the ground and that it was too late to abort. The pilot advanced the power lever all the way forward but the torque indication was only in the 80's percentile range. He pulled back on the control stick, and the main wheels left the ground, but the tail wheel felt like it was again on the ground. The pilot jettisoned the applicant load, but the airplane struck a fence in a nose high attitude approximately 100 feet from the end of the runway. The airplane tumbled and came to rest in a river approximately 350 feet from the fence. The airplane's turbine engine separated from the airframe, and both wings exhibited aft accordion leading edge crushing. The pilot stated that "a more prompt recognition of the problem and an earlier decision to dump the load [of applicant] may possibly have prevented the aircraft from hitting the fence." The pilot reported that when he arrived at the airport at 0500 the wind was light and variable. At 0615 the reported wind at Caldwell Industrial Airport, Caldwell, located 3 nautical miles from the accident site was wind from 110 degrees at 8 knots. During the postaccident examination, the Garrett AiResearch TPE331 turboshaft engine was removed from the accident scene and shipped to Honeywell Aerospace, Phoenix, Arizona. On August 1, 2013, a manufacturer's representative and a Federal Aviation Administration (FAA) inspector witnessed the disassembly of the engine. Additionally, the fuel control unit (FCU), propeller governor and P2T2 sensor were sent to Woodward, Inc., Rockford, Illinois, for examination under the supervision of an FAA inspector. At the conclusion of the examinations, no mechanical malfunctions or failures were found that would have precluded normal operation. ## Aircraft - Registration: [N7643J](https://openairdocs.org/deregistered/N7643J-2021-12-04), registration cancelled 2021-12-04, S/N 1Z025-18, built 1984 (OpenAirDocs) - Reported make and model: WSK PZL MIELEC M-18B - Registry model: [WSK PZL Mielec M-18A](https://openairdocs.org/model/wsk-pzl-mielec-m-18a) (registry code 9810103) (OpenAirDocs) - Registry engine: [Wsk-Pzl-K PZL ASZ-62IR](https://openairdocs.org/engine/wsk-pzl-k-pzl-asz-62ir) (registry code 67203, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 1Z025-18 - Year built: 1984 - Airframe hours: 6523 - Engines: Garrett AiResearch TPE331 940 horsepower turbo prop - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: Valley Air Service Inc - Registered owner: Valley Air Service Inc - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, February 1, 2013 - Departed: ID00, Caldwell, ID - Destination: ID00, Caldwell, ID - Airport: ID00, Hubler Field Airport, runway 28, 2,800 × 20 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 43; injuries: none; private, flight instructor, commercial; airplane ratings: multi-engine land, single-engine sea, single-engine land; instrument ratings: airplane; medical: class 2, with waivers/limitations; last flight review December 13, 2012; seat: front; restraint: 4-point; flight hours: 2,190 total, 105 in this make and model, 2,062 as pilot in command, 221 in the last 90 days, 128 in the last 30 days, 7 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 110° at 8 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 75 °F, dew point 57 °F - Altimeter: 30.04 inHg - Observed at: EUL, 4 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 20130703011769A](https://openairdocs.org/incident/20130703011769A), Jul 3, 2013: Wsk Pzl Mielec M-18A, Middleton, ID, Substantial damage. On 3 July, 2013, at approximately 0600, a Wsk Pzl Mielec, M-18A, N7643J, piloted by [privacy data omitted] took off from Hubler field (ID00) on runway 28. The… ## Other investigations on N7643J (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 FTW96LA325](https://openairdocs.org/ntsb/FTW96LA325), Jul 27, 1996: Pezetel M-18A (N7643J), Mcgehee, AR, substantial damage. Probable cause: failure of the brake system for undetermined reason(s), which resulted in a loss of directional control and a subsequent encounter with a ditch. ## Docket (4 files) The files NTSB released with the investigation on January 9, 2014, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=87389. 2.4 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 781 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40406115&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Weather Reports and Records (item 2, .PDF, 94 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40406116&FileExtension=.PDF&FileName=Weather%20Reports%20and%20Records-Master.PDF - Honeywell Powerplant Wreckage Review Notes (item 3, .PDF, 1.4 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40406117&FileExtension=.PDF&FileName=Honeywell%20Powerplant%20Wreckage%20Review%20Notes-Master.PDF - Statement of Party Representatives to NTSB Investigation (item 4, .PDF, 121 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40407537&FileExtension=.PDF&FileName=Statement%20of%20Party%20Representatives%20to%20NTSB%20Investigation-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.