# NTSB NYC08LA280: Socata MS894A, N31BF, Fulton, NY, August 16, 2008 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: August 16, 2008, 15:40 local (19:40 UTC) - Place: Fulton, NY - Coordinates: 43.32389, -76.385833 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=43.3239&lon=-76.3858&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Defining event: [Approach-VFR pattern crosswind: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) - Highest injury: Minor injuries - Injuries: 2 minor - Status: Completed, report October 21, 2010 - Report: Approved by Office Director - Parties: Rochester FSDO - NTSB case key (mKey): 68711 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=NYC08LA280 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/68711/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=68711 - Page: https://openairdocs.org/ntsb/NYC08LA280 ## Probable cause A loss of engine power due to fatigue failure of the crankshaft and the No. 3 engine cylinder connecting rod as a result of improper machining of the engine crankshaft during engine overhaul by maintenance personnel. ## 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: [S.O.C.A.T.A. MS894A, 1 case](https://openairdocs.org/ntsb-findings/01058520/cases.md?model=8402842), [All aircraft, 233 cases](https://openairdocs.org/ntsb-findings/01058520/cases.md) - [Maintenance: repair](https://openairdocs.org/ntsb-findings/02062015): Personnel issues › Task performance · Maintenance personnel (probable cause); cases with it: [S.O.C.A.T.A. MS894A, 1 case](https://openairdocs.org/ntsb-findings/02062015/cases.md?model=8402842), [All aircraft, 99 cases](https://openairdocs.org/ntsb-findings/02062015/cases.md) - [Action: incorrect action performance](https://openairdocs.org/ntsb-findings/02041015): Personnel issues › Action/decision · Maintenance personnel (probable cause); cases with it: [S.O.C.A.T.A. MS894A, 1 case](https://openairdocs.org/ntsb-findings/02041015/cases.md?model=8402842), [All aircraft, 1,386 cases](https://openairdocs.org/ntsb-findings/02041015/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Approach-VFR pattern crosswind: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) (defining event); cases with it: [S.O.C.A.T.A. MS894A, 1 case](https://openairdocs.org/ntsb-events/341/sequence.md?model=8402842), [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: [S.O.C.A.T.A. MS894A, 2 cases](https://openairdocs.org/ntsb-events/440/sequence.md?model=8402842), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) - [Emergency descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [S.O.C.A.T.A. MS894A, 2 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=8402842), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The pilot stated that he was level at 400 feet above ground level when he heard a "bang," the airplane began to vibrate, and the engine stopped. He lowered the nose for the airplane's best glide speed and initiated a forced landing to a nearby open field. While on final approach to the field the airplane collided with trees and then the ground. The crankshaft and connecting rod were forwarded to the Safety Board's Metallurgical Laboratory for further analysis. Examination of the crankshaft's ten bearing journals revealed surface finishes that were consistent with a turning operation but not with a grinding operation as specified in the overhaul manual. Examination of the engine assembly revealed that the crankshaft and the No. 3 engine cylinder connecting rod had failed. The examination revealed that the crankshaft failed in fatigue and initiated in machining marks in the rear radius of the No. 3 and 4 connecting rod bearing journals. An engine logbook entry indicated that the main and rod bearing journals had been "turned" and their diameter reduced by 0.010-inch in accordance with the Franklin overhaul manual. Journal diameters were measured and were consistent with 0.010-inch begin removed; however, the table in the overhaul manual specified a tolerance of 0.0010-inch and the dimensions indicated a tolerance of 0.0020-inch, which was contrary to the overhaul manual. The overhaul manual also recommends that the crankshafts be returned to the factory for grinding and re-nitriding. No logbook entries were located to verify that re-nitriding had been carried out. ## Factual narrative On August 16, 2008, at 1540 eastern daylight time, a Socata MS894A, N31BF, was substantially damaged during a forced landing following a loss of engine power, approximately 2 miles south of the Oswego County Airport (FZY), Fulton, New York. The certificated private pilot and passenger sustained minor injuries. Day visual meteorological conditions prevailed and no flight plan was filed for the personal local flight. The flight was conducted under the provisions of Title 14 Code of Federal Regulations Part 91. The airplane was owned by the pilot and based at FZY. It had been fueled on the morning of the accident with 22.2 gallons and a report from the lineman was that it was "topped off." According to the pilot after making a low pass along the drop zone, he pulled up and leveled off at about 400 feet above ground level. He then heard a "bang," followed by vibration, and then the engine stopped. He immediately pitched for a "glide speed of 90 miles per hour," and flew toward a field. On the final leg of the approach, the airplane impacted trees, nosed over on touchdown, and then rotated approximately 180 degrees. Examination of the airplane by a Federal Aviation Administration inspector revealed that control continuity was confirmed to all control surfaces from the control column and rudder pedals. Both propeller blades had slight "S-bending." Left had gear assembly was separated and located in front of the airplane. Inside the cockpit the throttle, propeller, and mixture controls were in the off or minimum position and the trim indicator was A preliminary inspection of the engine revealed that a hole was located in the case in the area near the number three piston and the No. 2 connecting rod was separated and located approximately 20 feet from the airplane along the direction of travel. Continuity could not be confirmed through the crankshaft and a further teardown examination revealed that the crankshaft was fractured at the connection point of the number three connecting rod. The oil filter was removed, examined, and contained metal particles throughout. According to the airplane's maintenance logbook the engine was overhauled on December 17, 2004. On April 2, 2005 due to a bearing recall the engine was disassembled, cleaned, and inspected. The crankshaft was "turned .010 on mains, .010 on rods" and was overhauled with a tachometer time of 1,548.63 hours. An annual inspection for the airplane was recorded on April 9, 2008 with a tachometer time of 1,576.81 hours. According to the pilot the airframe had a total time of 1,599 hours at the time of the accident. The recovered crankshaft and connecting rods were submitted to the National Transportation Safety Board Materials Laboratory Division. Examination of the fracture faces on cheek C4 revealed mechanical damage and three zones that displayed relatively smooth surfaced and arced cracked arrest marks which are consistent with fatigue. Measurements of the bearing journals revealed that thediameter of main journals M1 to M4 ranged between 2.2405 and 2.2385 inches a tolerance of 0.0020-inch, and the diameter of the rod journals ranged between 1.9280 and 1.9260 inches a tolerance of 0.0020-inch. According to the table limits in the overhaul manual the tolerance on the main and rod journals was 0.0010-inch. Examination of the connecting rod bearings revealed the numbers "18020" and according to the illustrated parts catalog, the standard bearing was "17739." Bearing journal R3 was cut adjacent to cheek C5 and revealed an arced initiation that followed a circumferential machining mark in the radius between the journal and the cheek. Bearing journals and crankshafts are normally surface hardened by a nitriding process and a sample from journal R3 was metallurgically mounted, polished and etched. Metallographic examination of the polished and etched sample revealed a uniform acicular (needle-like) structure in the base material and in the surface layer, consistent with tempered martensite. ## Aircraft - Registration: [N31BF](https://openairdocs.org/deregistered/N31BF-2010-08-31), registration cancelled 2010-08-31, S/N 11682, built 1971 (OpenAirDocs) - Reported make and model: SOCATA MS894A - Registry model: [S.O.C.A.T.A. MS894A](https://openairdocs.org/model/s-o-c-a-t-a-ms894a) (registry code 8402842) (OpenAirDocs) - Registry engine: [Franklin 6A-350SER](https://openairdocs.org/engine/franklin-6a-350ser) (registry code 27023, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 11682 - Airframe hours: 1599 - Engines: Franklin 6A-350-C1 220 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Utility; Standard, Normal - Last inspection: Annual, April 1, 2008, 23 hours before - Departed: FZY, Fulton, NY - Destination: FZY, Fulton, NY - Airport: FZY, Oswego County Airport, runway 35, 5,197 × 100 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 77; injuries: minor; private; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 3, with waivers/limitations; last flight review August 1, 2008; seat: left; flight hours: 4,316 total, 27 in this make and model, 4,146 as pilot in command, 18 in the last 90 days, 7 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 290° at 11 knots, gusting 17 - Visibility: 10 statute miles - Temperature: 75 °F, dew point 57 °F - Altimeter: 29.94 inHg - Observed at: FZY, 2 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 20080816849349A](https://openairdocs.org/incident/20080816849349A), Aug 16, 2008: Socata MS894A, Fulton, NY, Substantial damage. (-23) On 8/16/2008 at 1540 hours, N31BF, Socata model MS894A serial number: 11682 approx 1.5 miles south of oswego county airport (fzy) crashed in an open… ## Docket (10 files) The files NTSB released with the investigation on July 23, 2010, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=68711. 4.5 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 610 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40304465&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Pilot written statement (item 2, .PDF, 110 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40304466&FileExtension=.PDF&FileName=Pilot%20written%20statement-Redacted.PDF - Airplane Logbooks [Excerpts] (item 3, .PDF, 350 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40326826&FileExtension=.PDF&FileName=Airplane%20Logbooks%20%5BExcerpts%5D-Redacted.PDF - Materials Laboratory 15 - Factual Report 10-063 (item 4, .PDF, 544 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40332728&FileExtension=.PDF&FileName=Materials%20Laboratory%2015%20-%20Factual%20Report%2010-063-Master.PDF - Oswego Weather (item 5, .PDF, 12 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40326816&FileExtension=.PDF&FileName=Oswego%20Weather-Master.PDF - Franklin Aircraft Illustrated Part Catalog [Excerpts] (item 6, .PDF, 46 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40333620&FileExtension=.PDF&FileName=Franklin%20Aircraft%20Illustrated%20Part%20Catalog%20%5BExcerpts%5D-Master.PDF - Frankilin Aircraft Engine Overhaul Manual [Excerpts] (item 7, .PDF, 1.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40333621&FileExtension=.PDF&FileName=Frankilin%20Aircraft%20Engine%20Overhaul%20Manual%20%5BExcerpts%5D-Master.PDF - Photo 1: Airplane At Rest (Courtsey of the FAA) (item 8, .PDF, 525 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40326818&FileExtension=.PDF&FileName=Photo%201%3A%20Airplane%20At%20Rest%20(Courtsey%20of%20the%20FAA)-Master.PDF - Photo 2: Left Side of Airplane At Rest (Courtsey of the FAA) (item 9, .PDF, 511 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40326821&FileExtension=.PDF&FileName=Photo%202%3A%20Left%20Side%20of%20Airplane%20At%20Rest%20(Courtsey%20of%20the%20FAA)-Master.PDF - Photo 3: Hole Observed On Engine Case (Courtsey of the FAA) (item 10, .PDF, 529 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40326820&FileExtension=.PDF&FileName=Photo%203%3A%20Hole%20Observed%20On%20Engine%20Case%20(Courtsey%20of%20the%20FAA)-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.