# NTSB ERA20LA064: Cirrus SR22, N323SR, Kenansville, NC, January 2, 2020 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 3 · Limited · Final report - Date: January 2, 2020, 10:25 local (15:25 UTC) - Place: Kenansville, NC - Coordinates: 35.084999, -77.895278 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=35.0850&lon=-77.8953&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Eastern Region Aviation - Parties: Cirrus Aircraft, Continental Motors, FAA/ FSDO - NTSB case key (mKey): 100764 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA20LA064 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/100764/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=100764 - Page: https://openairdocs.org/ntsb/ERA20LA064 ## Probable cause A fatigue failure of the camshaft due to a manufacturing defect, which resulted in a partial loss of engine power. ## 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: [Cirrus Design SR22, 9 cases](https://openairdocs.org/ntsb-findings/01058520/cases.md?model=2130001), [All aircraft, 233 cases](https://openairdocs.org/ntsb-findings/01058520/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 (partial)](https://openairdocs.org/ntsb-events/342) (defining event); cases with it: [Cirrus Design SR22, 15 cases](https://openairdocs.org/ntsb-events/342/sequence.md?model=2130001), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) ## Analysis The pilot reported that, during a cross-country flight, he heard a pop from the engine, and it subsequently stopped producing power; however, the engine continued to run, and the propeller continued to rotate. The pilot attempted to troubleshoot the loss of power; however, power was not restored. Subsequently, the pilot activated the airplane’s parachute system and the airplane impacted trees and terrain, resulting in substantial damage to the airframe. Postacccident examination of the engine revealed that the camshaft fractured at one of its four oil transfer holes. As a result, camshaft continuity was lost, and the engine was partially unable to produce power. Forensic examination of the fracture surface revealed that the fracture occurred due to fatigue that initiated from a burr at the corner of an oil transfer hole. The extent of fatigue crack growth through the cross-section suggested the overall torsion load on the camshaft was relatively low as the crack grew. However, a burr at the edge of a hole is a feature that is known to reduce component fatigue life. The burr was deformed and coated, consistent with forming during a peening operation and before the manganese phosphate coating had been applied. A similar burr was also observed on the adjacent oil transfer hole in the camshaft. The presence of a burr suggests the corner of the hole was not properly broken before the part was peened during manufacturing, leading to deformation of a sharp corner during the peening operation. ## Factual narrative On January 2, 2020, about 1015 eastern standard time, a Cirrus Design Corp. SR-22, N323SR, was substantially damaged when it was involved in an accident near Kenansville, North Carolina. The commercial pilot and passenger were not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot reported that the departure and enroute phase of flight were normal for about 3.5 hours. While cruising at 6,500 ft mean sea level (msl), about 50 nautical miles from Curtis L Brown Jr. Field Airport (EYF), Elizabethtown, North Carolina, the airplane experienced three events nearly simultaneously. He first heard a “pop” that “wasn’t huge,” but caught his attention, then the autopilot disconnect aural alert sounded, and the airplane began “decelerating.” He stated that the airplane just began to “slow down” and the engine “wasn’t producing forward thrust.” However, the propeller continued to rotate, and when he viewed the engine instruments, the engine RPM continued to read 1,600 RPM, all exhaust gas temperature (EGT) gauges read 0° F, but no other engine instrument was red. He reported that he adjusted the throttle lever after the loss of engine power; when it moved, the lever felt normal, but had no effect on the engine power. He also switched the fuel tank selector, but the engine condition did not change. He maintained 88 knots indicated airspeed as the airplane descended, and about 2,000 ft msl while approaching an open field ahead, he activated the Cirrus Airframe Parachute System (CAPS). Subsequently, the CAPS deployed and the airplane “stopped and fell near vertically.” The airplane impacted trees, where it became partially suspended in branches, with its right-wing impacting terrain below. The airplane’s fuselage and wings sustained substantial damage. The National Transportation Safety Board (NTSB) Vehicle Recorders Division performed a download of the primary and multi-function displays. The data were largely consistent with what the pilot reported. The airplane’s flight and engine parameters were normal until a rapid drop in exhaust gas temperature (EGT) and oil pressure was observed in the final few minutes of data. Fuel flow remained consistent throughout the data, engine cylinder head temperatures were normal, and the engine rpm showed a slow decrease toward about 1,500 after the rapid drop in EGT was observed. Examination of the engine revealed that it sustained minor impact damage. When the engine was rotated by hand, the No. 1 and 2-cylinder intake and exhaust valves moved normally, however, the remaining four cylinder’s valves displayed no movement. With the engine partially disassembled, the engine was rotated by hand and the camshaft gear was observed to rotate normally with no observable wear on any of its associated gear teeth. The engine was further disassembled and the camshaft was found fractured. The camshaft, part number 654084, revision P, was examined further by the NTSB MaterialsLaboratory. According to the NTSB Materials Laboratory factual report, the camshaft had fractured between lobes associated with the No. 2 and 3 cylinders, intersecting oil transfer holes as shown in figure 1. The fracture plane was angled relative to the transverse plane consistent with fatigue fracture under torsion loading. The fracture surface was further forensically examined, which revealed relatively smooth fracture features with curving crack arrest lines, features consistent with fatigue. Crack arrest lines emanated from origins at the corner of the oil transfer hole where it intersected the camshaft exterior surface. Fatigue features were observed around most of the fracture surface, intersecting the oil transfer hole at the opposite side of the camshaft. A portion of the fracture had post-fracture rub damage that obliterated the fracture features. The exterior surface of the camshaft had a dimpled appearance, consistent with a shot-peened surface treatment. The corner of the oil transfer hole was deformed inward, forming a burr. Dimple features were also observed on the surface of the burr consistent with peening deformation. The oil transfer hole between lobes associated with the No. 4 and 5 cylinders also displayed a burr at the corner of the hole, but no crack was observed. Further forensic examination and cuts to the oil transfer hole found an elongated texture consistent with surface deformation associated with the burr formation. Maintenance records revealed that the engine was newly manufactured by Continental on July 15, 2017, and was installed on the airplane by Cornerstone Aviation on August 5, 2017. The airplane was inspected under annual/100-hour and Cirrus Progressive inspection protocols from the engine install date, with the most recent inspection competed on September 22, 2019. Review of the maintenance endorsements from July 2017 through the most recent inspection revealed no work that would have involved major disassembly of the engine. The engine had accumulated a total of 707 hours. Review of NTSB accident report ERA11LA130, January 27, 2011, involving a Cirrus SR22, Continental Motors IO-550-N, Camshaft Part Number 654084, revision D, revealed that the camshaft in that engine also fractured in-flight. The NTSB Materials Laboratory found that a fracture due to fatigue occurred at the most aft oil transfer hole. The report found that the engine had been overhauled about 393 hours prior to the incident. During the overhaul the original camshaft was replaced with a “repaired” camshaft and it was not determined whether any of the fatigue cracks were of detectible size at the time of installation. ## Aircraft - Registration: [N323SR](https://openairdocs.org/deregistered/N323SR-2023-02-04), registration cancelled 2023-02-04, S/N 2271, built 2006 (OpenAirDocs) - Reported make and model: Cirrus SR22 (NO SERIES) - Registry model: [Cirrus Design SR22](https://openairdocs.org/model/cirrus-design-sr22) (registry code 2130001) (OpenAirDocs) - Registry engine: [Continental IO-550-N](https://openairdocs.org/engine/continental-io-550-n) (registry code 17215, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 2271 - Year built: 2006 - Airframe hours: 3774.1 - Engines: Continental IO-550-N 310 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Cornerstone Aviation LLC. - Airworthiness certificate: Standard, Normal - Last inspection: Continuous airworthiness, September 22, 2019, 21 hours before - Departed: ORH, Worcester, MA - Destination: EYF, Elizabethtown, NC - Equipment: Electronic multifunction display, Auto-pilot, Airframe parachute, ADS-B, Stall warning system, Electronic primary flight display ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 66; injuries: none; commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2, with waivers/limitations; last flight review September 25, 2019; seat: left; restraint: 4-point; flight hours: 4,000 total, 2,738 in this make and model, 30 in the last 90 days ## Weather - Conditions: Visual (VMC), Day - Wind: 200° at 8 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 57 °F, dew point 36 °F - Altimeter: 30.11 inHg - Observed at: ISO, 20 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 20200102000639A](https://openairdocs.org/incident/20200102000639A), Jan 2, 2020: Cirrus Design Corp SR22, Kenansville, NC, Substantial damage. During cruise flight at 6,500 feet about 70NM of keyf airport, there was a ?pop? And the aircraft lost power while engine speed continued at 1600RPM. Engine… ## Docket (14 files) The files NTSB released with the investigation on March 24, 2022, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=100764. 27.2 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 4.8 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12958586&FileExtension=pdf&FileName=NTSB%206120%20Accident%20Report%20Form_Redacted-Rel.pdf - Airframe and engine examination report (item 2, PDF, 3 pages, 226 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13014648&FileExtension=pdf&FileName=Airframe%20and%20Engine%20Exam%20Report-Rel.pdf - Memo for record (virtual camshaft inspection) (item 3, PDF, 4 pages, 555 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12955422&FileExtension=pdf&FileName=Memo%20for%20Record%20(Virtual%20Camshaft%20Inspection_CMI)-Rel.pdf - Materials laboratory factual report 21-078 (item 4, PDF, 6 pages, 8 photos, 2.8 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12900636&FileExtension=pdf&FileName=21-078-Rel.pdf - Continental camshaft exam report - ouo (item 5, PDF, 3 pages, 4 photos, 1.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12955213&FileExtension=pdf&FileName=CMI%20Camshaft%20Exam%20Report%20-%20Redacted-Rel.pdf - Record of conversation (FAA inspector) (item 6, PDF, 1 page, 141 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12955223&FileExtension=pdf&FileName=Record%20of%20Conversation%20(FAA%20Inspector)-Rel.pdf - Record of conversation (pilot) (item 7, PDF, 2 pages, 212 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12958885&FileExtension=pdf&FileName=Record%20of%20Conversation%20(Pilot)-Rel.pdf - Photo array (item 8, PDF, 6 pages, 10 photos, 5.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12958900&FileExtension=pdf&FileName=Photo%20Array-Rel.pdf - Excerpts of maintenance records (item 9, PDF, 4 pages, 4.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12958910&FileExtension=pdf&FileName=Excerpts%20of%20Maintenance%20Records_Redacted-Rel.pdf - Cockpit displays - specialist's factual report (item 10, PDF, 13 pages, 8 photos, 1.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11581645&FileExtension=pdf&FileName=ERA20LA064-Rel.pdf - Cockpit displays - attachment 1 (tabular data) (item 11, CSV, 3.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11582881&FileExtension=csv&FileName=Attachment%201-Rel.csv - Cockpit displays - attachment 2 (tabular data) (item 12, CSV, 301 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11582265&FileExtension=csv&FileName=Attachment%202-Rel.csv - Statement of party representatives to NTSB investigation (item 13, PDF, 3 pages, 1.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12971892&FileExtension=pdf&FileName=Party%20Member%20Sign%20Pages%20-%20Redacted-Rel.pdf - Release of aircraft wreckage, NTSB form 6120.15 (item 14, PDF, 7 pages, 1.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13070414&FileExtension=pdf&FileName=NTSB%20Release%20of%20Wreckage%20-%20Redacted_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.