# NTSB GAA15LA092: Czech Aircraft Works Spol Sro Sportcruiser, N642JB, Fresno, CA, May 24, 2015 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: May 24, 2015, 14:45 local (21:45 UTC) - Place: Fresno, CA - Coordinates: 36.732498, -119.820831 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=36.7325&lon=-119.8208&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing-landing roll: Landing gear collapse](https://openairdocs.org/ntsb-events/094) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report January 21, 2016 - Report: Approved by Office Director - NTSB office: General Aviation Accidents - Parties: Air Accidents Investigation Institute (AAII), FAA Fresno FSDO - NTSB case key (mKey): 91252 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=GAA15LA092 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/91252/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=91252 - Page: https://openairdocs.org/ntsb/GAA15LA092 ## Probable cause The failure of the nose landing gear (NLG) leg due to fatigue fractures, which resulted in the NLG collapsing during landing. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Landing gear system: nose/tail landing gear](https://openairdocs.org/ntsb-findings/01023220): Aircraft › Aircraft systems · Fatigue/wear/corrosion (probable cause); cases with it: [Czech Aircraft Works Spol Sro SPORTCRUISER, 1 case](https://openairdocs.org/ntsb-findings/01023220/cases.md?model=060002O), [All aircraft, 185 cases](https://openairdocs.org/ntsb-findings/01023220/cases.md) - [Landing gear system: nose/tail landing gear](https://openairdocs.org/ntsb-findings/01023220): Aircraft › Aircraft systems · Failure (probable cause); cases with it: [Czech Aircraft Works Spol Sro SPORTCRUISER, 1 case](https://openairdocs.org/ntsb-findings/01023220/cases.md?model=060002O), [All aircraft, 185 cases](https://openairdocs.org/ntsb-findings/01023220/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Landing-landing roll: Sys/Comp malf/fail (non-power)](https://openairdocs.org/ntsb-events/330); cases with it: [Czech Aircraft Works Spol Sro SPORTCRUISER, 3 cases](https://openairdocs.org/ntsb-events/330/sequence.md?model=060002O), [All aircraft, 994 cases](https://openairdocs.org/ntsb-events/330/sequence.md) - [Landing-landing roll: Landing gear collapse](https://openairdocs.org/ntsb-events/094) (defining event); cases with it: [Czech Aircraft Works Spol Sro SPORTCRUISER, 4 cases](https://openairdocs.org/ntsb-events/094/sequence.md?model=060002O), [All aircraft, 1,787 cases](https://openairdocs.org/ntsb-events/094/sequence.md) - [Landing-landing roll: Abnormal runway contact](https://openairdocs.org/ntsb-events/090); cases with it: [Czech Aircraft Works Spol Sro SPORTCRUISER, 5 cases](https://openairdocs.org/ntsb-events/090/sequence.md?model=060002O), [All aircraft, 1,506 cases](https://openairdocs.org/ntsb-events/090/sequence.md) ## Analysis The pilot reported that, during the third landing of the flight and as the nose landing gear (NLG) touched down, an immediate shimmy developed that sounded "clunky." The NLG subsequently collapsed, and the light-sport airplane then skidded to a stop on the runway and sustained substantial damage to the firewall. The pilot stated that the landing flare was "normal" and that the main landing gear touched down first. He reported that there were no anomalies with the landing gear during the previous two landings. Examination of the NLG assembly revealed that the NLG leg was fractured at the weld joint in the upper attachment area and that the fracture features were consistent with fatigue cracking. Multiple fatigue fracture origins were found at the forward edge of the assembly weld on the left side of the NLG leg. The fatigue crack penetrated about 50 percent of the NLG leg's cross-section and was consistent with side-to-side loading of the leg. ## Factual narrative On May 24, 2015, about 1445 pacific daylight time, a Czech Aircraft Works Spol Sro SportCruiser airplane, N642JB, experienced a nose gear collapse during landing at Fresno Chandler Executive Airport, Fresno, California. The solo pilot was not injured. The airplane was registered to a private owner and was operated by the pilot as a 14 Code of Federal Regulations Part 91 personal flight. Day visual meteorological conditions prevailed for the flight, with no flight plan filed. The flight departed from Fresno Chandler Executive Airport (FCH), and remained in the traffic pattern. According to the pilot, on the third landing, as the nose gear touched down, an immediate shimmy developed that sounded "clunky." During the landing roll, the nose gear collapsed and the airplane skidded to a stop on the runway. The pilot stated that the landing flare was "normal" and the main landing gear touched down first. The pilot reported that during the first two landings there were no anomalies with the nose landing gear. The airplane sustained substantial damage to the firewall. The nose gear assembly was sent to the National Transportation Safety Board (NTSB) Materials Laboratory, in Washington, DC, for further examination. The nose gear leg assembly is comprised of one inch in diameter bent tubing (leg) with welded brackets at each end to facilitate the fastening of the nose gear leg to the fuselage at the firewall, and the wheel assembly at the opposite end of the leg. The examination revealed that the leg of the nose gear was fractured through the tube at the weld joint in the upper attachment area. Optical examinations of the fracture face revealed separation topographies, beach marks, and recontact damage consistent with progressive fatigue cracking. A closer magnified viewing uncovered multiple fatigue fracture origins at the forward toe (edge) of the assembly weld on the left side of the tube. The fatigue penetrated a total of about 50 percent of the total tube cross section and was consistent with side to side loading of the tube. The fracture through the remaining tube cross sections was consistent with overstress. AIRCRAFT INFORMATION The airplane had accumulated 870.1 total hours of operation since new. The most recent annual inspection was completed on May 11th, 2015 and the airplane had accrued 2.0 hours of operation since that inspection. During an interview with the National Transportation Safety Board (NTSB) investigator -in-charge (IIC), the airplane owner, who is a Light Sport Aircraft Repairman, stated nothing abnormal was noted with the nose gear leg assembly during the most recent annual inspection, which he performed. He also reported that the nose gear leg that was on the airplane at the time of the accident was a "second generation" nose gear (SG0270N), but further consultation with the airplane manufacturer identified the nose gear as a first generation nose gear leg (SG0040N). ADDITIONAL INFORMATION The first generation nose gear assemblythat was on this airplane was manufactured by Czech Aircraft Works (CZAW), a company that became insolvent in 2009. According to Czech Sport Aircraft, who was the company providing continued airworthiness support for all SportCruiser airplanes; there have been a number of upgrades and design changes to the nose gear. On July 10th, 2014, Czech Sport Aircraft issued a service bulletin containing instructions to replace the nose landing gear with an "Improved Nose Landing Gear Assembly (SG0300N)". The service bulletin states, "Some PS-28 Cruiser / SportCruiser / PiperSport aircraft have developed cracks in the bottom side of the lower section of the nose landing gear (NLG) SG0270N. To address this potential condition, CSA has issued service bulletin SB-CR-016 that prescribes an inspection of the of the nose landing gear SG0270N. Subsequently, CSA have developed an improved NLG SG0300N, which has better fatigue-resistant properties." Compliance with this service bulletin was not required by the Federal Aviation Administration and is an "aircraft owner decision." ## Aircraft - Registration: [N642JB](https://openairdocs.org/aircraft/N642JB), registered now, S/N 08SC243, built 2008 (OpenAirDocs) - Reported make and model: CZECH AIRCRAFT WORKS SPOL SRO SPORTCRUISER (A) - Registry model: [Czech Aircraft Works Spol Sro SPORTCRUISER](https://openairdocs.org/model/czech-aircraft-works-spol-sro-sportcruiser) (registry code 060002O) (OpenAirDocs) - Registry engine: [Rotax 912ULS series](https://openairdocs.org/engine/rotax-912uls-series) (registry code 55572, 4 cycle) (OpenAirDocs) - Category: Airplane - Serial number: 08SC243 - Year built: 2008 - Airframe hours: 870.1 - Engines: Rotax 912ULS 100 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Special, Special light-sport (Special) - Last inspection: Annual, May 11, 2015, 2 hours before - Departed: FCH, Fresno, CA - Destination: FCH, Fresno, CA - Airport: FCH, Fresno Chandler Executive, runway 30, 3,627 × 75 ft, asphalt - Equipment: Electronic primary flight display, Handheld GPS, ADS-B, Auto-pilot, Electronic flight bag or handheld device, Electronic multifunction display ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 55; injuries: none; sport pilot; airplane ratings: single-engine land; medical: sport pilot; last flight review May 30, 2014; seat: left; restraint: 3-point; flight hours: 252 total, 221 in this make and model, 211 as pilot in command, 1 in the last 90 days, 1 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: variable at 5 knots - Visibility: 10 statute miles - Temperature: 81 °F, dew point 50 °F - Altimeter: 29.93 inHg - Observed at: KFAT, 6 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 20150524011309A](https://openairdocs.org/incident/20150524011309A), May 24, 2015: Czech Aircraft Works Spol Sro SPORTCRUISER, Fresno, CA, Minor damage. Aircraft made a hard landing. After landing aircraft had excessive nose wheel shimmy and gear collapsed. ## Docket (8 files) The files NTSB released with the investigation on December 9, 2015, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=91252. 4.4 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 2.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40434751&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Record of Conversation (FAA Inspector) (item 2, .PDF, 53 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40434752&FileExtension=.PDF&FileName=Record%20of%20Conversation%20(FAA%20Inspector)-Master.PDF - Record of Conversation (Pilot in Command) (item 3, .PDF, 55 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40434753&FileExtension=.PDF&FileName=Record%20of%20Conversation%20(Pilot%20in%20Command)-Master.PDF - Record of Conversation (Airplane Owner) (item 4, .PDF, 166 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40434754&FileExtension=.PDF&FileName=Record%20of%20Conversation%20(Airplane%20Owner)-Master.PDF - Airplane Maintenance Manual Excerpts (item 5, .PDF, 36 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40434756&FileExtension=.PDF&FileName=Airplane%20Maintenance%20Manual%20Excerpts-Master.PDF - Czech Sport Aircraft Notification of Continued Airworthiness Support (item 6, .PDF, 68 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40434757&FileExtension=.PDF&FileName=Czech%20Sport%20Aircraft%20Notification%20of%20Continued%20Airworthiness%20Support-Master.PDF - Evidence Control Form (item 7, .PDF, 160 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40434758&FileExtension=.PDF&FileName=Evidence%20Control%20Form-Master.PDF - Docket Photos (Courtesy of FAA and Airport Manager) (item 8, .PDF, 3 photos, 1.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40434759&FileExtension=.PDF&FileName=Docket%20Photos%20(Courtesy%20of%20FAA%20and%20Airport%20Manager)-Master.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.