# NTSB CEN12LA309: Quicksilver Sprint II, N3521A, Lebanon, IL, May 19, 2012 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: May 19, 2012, 18:00 local (23:00 UTC) - Place: Lebanon, IL - Coordinates: 38.610279, -89.871391 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=38.6103&lon=-89.8714&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Defining event: [Initial climb: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) - Highest injury: Minor injuries - Injuries: 2 minor - Status: Completed, report August 29, 2012 - Report: Approved by Office Director - NTSB office: Central Region - Parties: Federal Aviation Administration - St. Louis FSDO - NTSB case key (mKey): 83716 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN12LA309 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/83716/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=83716 - Page: https://openairdocs.org/ntsb/CEN12LA309 ## Probable cause The total loss of engine power due to a fatigue failure of the crankshaft, attributed to the relative movement between the crankshaft and flywheel assembly. ## 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: [Quicksilver SPRINT II, 1 case](https://openairdocs.org/ntsb-findings/01058520/cases.md?model=059008M), [All aircraft, 233 cases](https://openairdocs.org/ntsb-findings/01058520/cases.md) - [Engine (reciprocating): recip engine power section](https://openairdocs.org/ntsb-findings/01058520): Aircraft › Aircraft power plant · Fatigue/wear/corrosion (probable cause); cases with it: [Quicksilver SPRINT II, 1 case](https://openairdocs.org/ntsb-findings/01058520/cases.md?model=059008M), [All aircraft, 233 cases](https://openairdocs.org/ntsb-findings/01058520/cases.md) - [Terrain: rough terrain](https://openairdocs.org/ntsb-findings/03021015): Environmental issues › Physical environment · Contributed to outcome; cases with it: [Quicksilver SPRINT II, 1 case](https://openairdocs.org/ntsb-findings/03021015/cases.md?model=059008M), [All aircraft, 442 cases](https://openairdocs.org/ntsb-findings/03021015/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 (total)](https://openairdocs.org/ntsb-events/341) (defining event); cases with it: [Quicksilver SPRINT II, 1 case](https://openairdocs.org/ntsb-events/341/sequence.md?model=059008M), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md) - [Landing: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Quicksilver SPRINT II, 1 case](https://openairdocs.org/ntsb-events/440/sequence.md?model=059008M), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) - [Landing-flare/touchdown: Roll over](https://openairdocs.org/ntsb-events/097); cases with it: [Quicksilver SPRINT II, 1 case](https://openairdocs.org/ntsb-events/097/sequence.md?model=059008M), [All aircraft, 261 cases](https://openairdocs.org/ntsb-events/097/sequence.md) ## Analysis The pilot reported that there were no anomalies during the before-takeoff engine run-up or when he applied power for takeoff. He stated that during the initial climb, about 35 feet above the ground, the engine suddenly lost power. The pilot reported that he reduced pitch in order to maintain airspeed but that the airplane impacted the ground in a nose-low attitude. The airplane immediately nosed over at impact, coming to rest inverted. A postaccident examination of the engine revealed that the crankshaft had fractured at the flywheel/crankshaft interface as a result of fatigue. The fracture originated from a single initiation point on the outer crankshaft surface that coincided with circumferential wear marks indicative of fretting. The observed wear marks matched those found on the flywheel and were likely the result of relative movement between the crankshaft and flywheel. The engine had accumulated 152.9 hours since new. ## Factual narrative On May 19, 2012, at 1800 central daylight time, a Quicksilver Sprint II experimental light-sport airplane, N3521A, was substantially damaged during a forced landing following a loss of engine power shortly after a takeoff from a private airstrip near Lebanon, Illinois. The sport pilot and passenger sustained minor injuries. The airplane was registered to and operated by the pilot under the provisions of 14 Code of Federal Regulations Part 91. Day visual meteorological conditions prevailed for the personal flight, which was operated without a flight plan. The local flight was originating at the time of the accident. The pilot reported that there were no anomalies with the engine operation during a before-takeoff engine check or when he applied power for takeoff. He stated that during initial climb, about 35 feet above the ground, the engine suddenly lost power. The pilot reported that he reduced pitch in order to maintain airspeed, but the airplane impacted the terrain in a nose low attitude. The airplane immediately nosed over at impact, coming to rest inverted. The fuselage, empennage, and wings were substantially damaged during the accident sequence. The closest weather observing station was at the Scott Air Force Base/MidAmerica Airport (KBLV), located about 5 miles south-southeast of the accident site. At 1755, the KBLV automated surface observing system reported the following weather conditions: wind 180 degrees at 9 knots; visibility 10 miles; clear skies; temperature 30 degrees Celsius; dew point 15 degrees Celsius; altimeter setting 29.97 inches of mercury. The non-certificated Hirth model 3202 engine, serial number 900607, was manufactured by Göbler-Hirth Engines Ltd in Benningen, Germany, and imported into the United States by their authorized distributor, Recreational Power Engineering of Tiffin, Ohio. The engine was sold to the owner-of-record on July 16, 2007, as a short-block engine assembly that did not include a gearbox, exhaust, electric starter, or fuel injection system. The owner reportedly transferred the additional components from another engine. The engine was installed on the accident airplane on July 30, 2007. The last conditional inspection of the airplane and engine was completed on May 20, 2011. When the accident occurred, the engine had accumulated 152.9 hours since new. On June 01, 2012, the engine was disassembled by the owner/pilot under the supervision of inspectors with the Federal Aviation Administration. The engine disassembly revealed that the crankshaft had fractured at the flywheel/crankshaft interface. The crankshaft and flywheel assemblies were sent to the National Transportation Safety Board's (NTSB) Materials Laboratory Division for metallurgical examination. The crankshaft fracture surface contained crack arrest marks and tear ridges indicative of fatigue. The direction of the observed crack arrest marks revealed a single initiation point on the outer crankshaft surface. The location of the fractureorigin coincided with wear marks, consistent with fretting, in a circumferential manner on the outer surface of the crankshaft. The observed wear marks matched those found on the flywheel female taper, consistent with relative movement between the crankshaft and flywheel. Mechanical smearing and chipping damage precluded further examination of the fracture origin. The fatigue fracture propagated through about 90-percent of the crankshaft cross-section. The remaining 10-percent of the crankshaft cross-section exhibited features consistent with overstress. Circumferential wear patterns were noted on the inner surface of the flywheel cylindrical magnet, which also contained accumulated metallic debris. ## Aircraft - Registration: [N3521A](https://openairdocs.org/deregistered/N3521A-2017-07-07), registration cancelled 2017-07-07, S/N A10KAS, built 1993 (OpenAirDocs) - Reported make and model: QUICKSILVER Sprint II - Registry model: [Quicksilver SPRINT II](https://openairdocs.org/model/quicksilver-sprint-ii) (registry code 059008M) (OpenAirDocs) - Registry engine: [Hirth 3203](https://openairdocs.org/engine/hirth-3203) (registry code 33733, 2 cycle) (OpenAirDocs) - Category: Airplane - Serial number: A10KAS - Airframe hours: 956 - Engines: Hirth 3203 65 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Special, Experimental light sport (Special) - Last inspection: Condition, May 20, 2011 - Departed: PVT, Lebanon, IL - Destination: PVT, Lebanon, IL - Airport: PVT, Private Airstrip, runway 09, 980 × 40 ft, grass/turf ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 51; injuries: minor; sport pilot; airplane ratings: single-engine land; medical: sport pilot; last flight review May 22, 2010; seat: left; flight hours: 225 total, 89 in this make and model, 205 as pilot in command, 2 in the last 90 days, 1 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 180° at 9 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 86 °F, dew point 59 °F - Altimeter: 29.96 inHg - Observed at: KBLV, 5 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 20120519013129A](https://openairdocs.org/incident/20120519013129A), May 19, 2012: Quicksilver SPRINT II, Lebanon, IL, Substantial damage. On 5/19/2012 aircraft took off at 1815 local. This was the second flight of the day. Pilot and one passenger aboard. Preflight checks were normal, during climb… ## Docket (8 files) The files NTSB released with the investigation on July 6, 2012, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=83716. 3.8 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 658 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40371433&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - FAA Inspector Statement (item 2, .PDF, 485 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40371434&FileExtension=.PDF&FileName=FAA%20Inspector%20Statement-Redacted.PDF - Materials Laboratory Factual Report 12-067 (with 8 embedded images) (item 3, .PDF, 1.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40370931&FileExtension=.PDF&FileName=Materials%20Laboratory%20Factual%20Report%2012-067%20(with%208%20embedded%20images)-Master.PDF - Hirth model 3203 Specifications Sheet (item 4, .PDF, 524 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40371435&FileExtension=.PDF&FileName=Hirth%20model%203203%20Specifications%20Sheet-Master.PDF - Airframe/Engine Maintenance Logbook Information (Excerpts) (item 5, .PDF, 306 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40371436&FileExtension=.PDF&FileName=Airframe%2FEngine%20Maintenance%20Logbook%20Information%20(Excerpts)-Redacted.PDF - Recreational Power Engineering Invoices for Hirth model 3203 (s/n 900607) (item 6, .PDF, 95 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40371437&FileExtension=.PDF&FileName=Recreational%20Power%20Engineering%20Invoices%20for%20Hirth%20model%203203%20(s%2Fn%20900607)-Redacted.PDF - Weather Reports (item 7, .PDF, 75 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40371438&FileExtension=.PDF&FileName=Weather%20Reports-Master.PDF - Retained Evidence Return Form (item 8, .PDF, 314 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40371853&FileExtension=.PDF&FileName=Retained%20Evidence%20Return%20Form-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.