# NTSB ERA16LA164: Piper PA28, N151DC, Okeechobee, FL, April 18, 2016 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Class 3 · Limited · Final report - Date: April 18, 2016, 15:30 local (19:30 UTC) - Place: Okeechobee, FL - Coordinates: 27.434999, -80.677223 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=27.4350&lon=-80.6772&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Eastern Region Aviation - Parties: FAA FSDO, Piper - NTSB case key (mKey): 93030 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA16LA164 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/93030/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=93030 - Page: https://openairdocs.org/ntsb/ERA16LA164 ## Probable cause The failure of the No. 3 piston due to fatigue cracking, which resulted in a total loss of engine power and subsequent forced landing, during which the airplane impacted obstacles. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Engine (reciprocating): recip engine power section](https://openairdocs.org/ntsb-findings/01058520): Aircraft › Aircraft power plant · Failure (probable cause); cases with it: [Piper PA-28-161, 2 cases](https://openairdocs.org/ntsb-findings/01058520/cases.md?model=7102803), [All aircraft, 233 cases](https://openairdocs.org/ntsb-findings/01058520/cases.md) - [Performance/control parameters: altitude](https://openairdocs.org/ntsb-findings/01062012): Aircraft › Aircraft oper/perf/capability · Attain/maintain not possible (probable cause); cases with it: [Piper PA-28-161, 7 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md?model=7102803), [All aircraft, 1,310 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md) - [Object/animal/substance: ground vehicle](https://openairdocs.org/ntsb-findings/03022025): Environmental issues › Physical environment · Contributed to outcome (probable cause); cases with it: [Piper PA-28-161, 3 cases](https://openairdocs.org/ntsb-findings/03022025/cases.md?model=7102803), [All aircraft, 132 cases](https://openairdocs.org/ntsb-findings/03022025/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) (defining event); cases with it: [Piper PA-28-161, 22 cases](https://openairdocs.org/ntsb-events/341/sequence.md?model=7102803), [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: [Piper PA-28-161, 19 cases](https://openairdocs.org/ntsb-events/440/sequence.md?model=7102803), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) - [Landing-landing roll: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Piper PA-28-161, 58 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=7102803), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The operator reported that the pilot was conducting a cross-country, solo instructional flight. When the airplane was about 3,000 ft mean sea level, the engine suddenly started running roughly accompanied by “abnormal” noises. The pilot attempted to troubleshoot the problem by performing the “engine roughness” checklist to no avail. About 10 seconds after completing the checklist, the engine lost all power. The pilot then established the best glide speed, chose a private grass strip for a forced landing, and conducted the “engine power loss in flight” checklist without success. Once committed to landing, he conducted the “power off landing checklist.” After the airplane touched down about halfway down the grass strip it skidded and subsequently impacted farm equipment and other obstacles, and it then came to rest against a building. The airplane sustained substantial damage to the fuselage and tail section, and the wings were sheared off. Examination of the engine revealed that there was a hole in the crankcase above the No. 2 cylinder, consistent with a catastrophic engine failure, and that the No. 3 piston had failed. Metallurgical examination of the No. 3 piston revealed that two fatigue cracks had emanated from the outer face of a lubricating hole, which resulted in the piston failing, ancillary damage to the cylinder and engine, and a subsequent total loss of engine power. The areas outside of the fatigue crack regions and fracture faces exhibited a rough texture and on-slant planes consistent with overstress separation. The reason for the initiation and propagation of the fatigue cracks could not be determined. Even though the engine was 200 hours past the manufacturer’s recommended time before overhaul limit, it could not be determined if that contributed to the fatigue cracking. ## Factual narrative On April 18, 2016, about 1530 Eastern daylight time, a Piper PA-28-161, N151DC, was substantially damaged when it was involved in an accident near Okeechobee, Florida. The pilot sustained minor injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 solo instructional flight. The operator reported that, when the airplane was about 3,000 ft mean sea level, the engine suddenly started to run roughly accompanied by “abnormal” noises. The engine instruments remained in the normal range. The pilot attempted to troubleshoot the problem by performing the “engine roughness” checklist without success. Shortly after, the pilot contacted the Miami Air Route Traffic Control Center and reported the problem, and a controller suggested that the pilot proceed to the St Lucie County International Airport (FPR), Fort Pierce, Florida, where emergency services would be standing by. However, about 10 seconds after completing the checklist, the engine lost all power. The pilot then established the best glide speed and chose a private grass strip for forced landing and conducted the “engine power loss in flight” checklist without success. Once committed to landing, he conducted the “power off landing checklist.” After touching down, the airplane skidded and subsequently impacted farm equipment and other obstacles, and it then came to rest against a building. A review of the engine’s maintenance records revealed that it had accrued 10,382.8 total flight hours and 2,600.8 hours since the last overhaul. The engine manufacturer’s recommended time between overhaul was 2,400 hours. Postaccident examination of the airplane revealed that it had sustained substantial damage to the fuselage and tail section and that the wings had been sheared off. During postaccident examination of the engine, a hole was found in the crankcase above the No. 2 cylinder. Metal was found in most of the folds of the oil filter material and in the Nos. 3 and 4 cylinders, and ferrous and nonferrous materials were found throughout the crankcase. During a subsequent compression check, the No. 3 cylinder’s compression was excessively low, The No. 3 piston would not move when the crankshaft was manually rotated. After the No. 3 cylinder was removed, only the connecting rod and piston pin were found. The No. 3 cylinder’s interior was extensively damaged. Metallurgical examination of the No. 3 piston revealed that it was fractured and that it had two fatigue cracks emanating from the outer face of a lubricating hole in a groove for a compression ring. (See figure 1, which is a photograph showing the two fatigue cracks in the No. 3 piston in relation to the lubricating hose and compression ring groove. The white arrows indicate the general direction of the fatigue crack propagation.) The areas outside of the fatigue crack regions and fracture faces exhibited a rough texture and on-slant planes consistent with overstress separation. The reason for the initiation and propagationof the fatigue cracks could not be determined. Figure 1. Photograph showing the No. 3 piston’s two fatigue cracks in relation to the lubricating hole and compression ring groove and the general direction of the fatigue propagation. ## Aircraft - Registration: [N151DC](https://openairdocs.org/deregistered/N151DC-2016-08-26), registration cancelled 2016-08-26, S/N 2842138, built 2001 (OpenAirDocs) - Reported make and model: PIPER PA28 (161) - Registry model: [Piper PA-28-161](https://openairdocs.org/model/piper-pa-28-161) (registry code 7102803) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 2842138 - Year built: 2001 - Airframe hours: 4577 - Engines: LYCOMING 0-320 SERIES 160 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Operator: Flightsafety International Inc - Registered owner: Flightsafety International Inc - Airworthiness certificate: Standard, Utility; Standard, Normal - Last inspection: AAIP, April 15, 2016, 3 hours before - Departed: APF, NAPLES, FL - Destination: VRB, VERO BEACH, FL - Flight plan: VFR - Equipment: Stall warning system ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 23; injuries: minor; private; airplane ratings: single-engine land; medical: class 1, without waivers/limitations; last flight review March 21, 2016; seat: left; restraint: 3-point; flight hours: 84 total, 84 in this make and model, 26 as pilot in command, 43 in the last 90 days, 16 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 60° at 9 knots, gusting 18 - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 77 °F, dew point 55 °F - Altimeter: 30.15 inHg - Observed at: OBE, 16 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 20160418004109A](https://openairdocs.org/incident/20160418004109A), Apr 18, 2016: Piper PA-28-161, Okeechobee, FL, Destroyed. On April 18th 2016 around 1530 a Piper-28 registration number N151DC serial number 2842138 had mid-flight engine failure which resulted in off airport landing… ## Docket (8 files) The files NTSB released with the investigation on February 23, 2021, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=93030. 6.7 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 9 pages, 3.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11821444&FileExtension=pdf&FileName=Accident%20Report_Redacted-Rel.pdf - Maintenance logs excerpt (item 2, PDF, 6 pages, 1.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11878017&FileExtension=pdf&FileName=N151DC_Maintenance%20Log%20Excerpt_Redacted-Rel.pdf - FAA inspectors statement (item 3, PDF, 3 pages, 118 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11876329&FileExtension=pdf&FileName=FAA%20Inspectors%20Statement_Redacted-Rel.pdf - Memo for record_operators email summary on the aaip (item 4, PDF, 1 page, 171 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11880003&FileExtension=pdf&FileName=Memorandum%20for%20Record-Email%20Summary%20of%20AAIP-Rel.pdf - Materials laboratory (item 5, PDF, 4 pages, 4 photos, 521 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11886235&FileExtension=pdf&FileName=16-085%20-%20%233%20piston%20and%20cylinder-Rel.pdf - Photo array_accident site and damage (item 6, PDF, 3 pages, 387 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11878484&FileExtension=pdf&FileName=Accident%20Site%20and%20Damage%20Photographs-Rel.pdf - Party form_manufacturer (item 7, PDF, 14 pages, 283 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11886479&FileExtension=pdf&FileName=Party%20Form_Piper_Redacted-Rel.pdf - Evidence control forms (item 8, PDF, 2 pages, 1.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11886566&FileExtension=pdf&FileName=Evidence%20Control%20Form_Engine%20Case%20and%20Internals_Redacted-Rel.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.