# NTSB ERA16LA004: Beech 58, N25734, Albany, GA, October 6, 2015 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: October 6, 2015, 19:00 local (23:00 UTC) - Place: Albany, GA - Coordinates: 31.535833, -84.186668 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=31.5358&lon=-84.1867&mi=10 - Phase of flight: [Taxi](https://openairdocs.org/ntsb-phases/250) (OpenAirDocs' grouping) - Defining event: [Taxi-from runway: Sys/Comp malf/fail (non-power)](https://openairdocs.org/ntsb-events/330) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report May 1, 2017 - Report: Approved by Office Director - NTSB office: Eastern Region Aviation - Parties: FAA/FSDO - NTSB case key (mKey): 92134 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA16LA004 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/92134/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=92134 - Page: https://openairdocs.org/ntsb/ERA16LA004 ## Probable cause The mechanic's inadequate inspection of the brake system during the most recent annual inspection, which resulted in the failure of both left and right main landing gear torque plates and a subsequent loss of braking action. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Landing gear system: landing gear brakes system](https://openairdocs.org/ntsb-findings/01023240): Aircraft › Aircraft systems · Fatigue/wear/corrosion (probable cause); cases with it: [Beech 58, 1 case](https://openairdocs.org/ntsb-findings/01023240/cases.md?model=1152740), [All aircraft, 92 cases](https://openairdocs.org/ntsb-findings/01023240/cases.md) - [Landing gear system: landing gear brakes system](https://openairdocs.org/ntsb-findings/01023240): Aircraft › Aircraft systems · Inadequate inspection (probable cause); cases with it: [Beech 58, 1 case](https://openairdocs.org/ntsb-findings/01023240/cases.md?model=1152740), [All aircraft, 92 cases](https://openairdocs.org/ntsb-findings/01023240/cases.md) - [Landing gear system: landing gear brakes system](https://openairdocs.org/ntsb-findings/01023240): Aircraft › Aircraft systems · Failure (probable cause); cases with it: [Beech 58, 1 case](https://openairdocs.org/ntsb-findings/01023240/cases.md?model=1152740), [All aircraft, 92 cases](https://openairdocs.org/ntsb-findings/01023240/cases.md) - [Maintenance: scheduled/routine maintenance](https://openairdocs.org/ntsb-findings/02062010): Personnel issues › Task performance · Maintenance personnel (probable cause); cases with it: [Beech 58, 2 cases](https://openairdocs.org/ntsb-findings/02062010/cases.md?model=1152740), [All aircraft, 320 cases](https://openairdocs.org/ntsb-findings/02062010/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Prior to flight: Aircraft maintenance event](https://openairdocs.org/ntsb-events/040); cases with it: [Beech 58, 5 cases](https://openairdocs.org/ntsb-events/040/sequence.md?model=1152740), [All aircraft, 484 cases](https://openairdocs.org/ntsb-events/040/sequence.md) - [Taxi-from runway: Sys/Comp malf/fail (non-power)](https://openairdocs.org/ntsb-events/330) (defining event); cases with it: [Beech 58, 6 cases](https://openairdocs.org/ntsb-events/330/sequence.md?model=1152740), [All aircraft, 994 cases](https://openairdocs.org/ntsb-events/330/sequence.md) - [Taxi-from runway: Loss of control on ground](https://openairdocs.org/ntsb-events/230); cases with it: [Beech 58, 2 cases](https://openairdocs.org/ntsb-events/230/sequence.md?model=1152740), [All aircraft, 4,585 cases](https://openairdocs.org/ntsb-events/230/sequence.md) - [Taxi-from runway: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Beech 58, 19 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=1152740), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis While taxiing from the runway after landing, the commercial pilot noted "softness" when he applied the left brake. Upon entering the ramp area, he further applied the brakes and attempted to slow the airplane; however, the brakes had no effect. The airplane rolled off the ramp, into the grass, and impacted an airport perimeter fence. Examination of both left and right main landing gear brake torque plates revealed that they had fractured in fatigue, and that the fatigue cracks emanated from corrosion pitting within the attachment bolt holes. The corrosion pits in the attachment bolt holes were stress risers that likely reduced the strength of the plates. It is likely that, during the most recent maintenance inspection, about 7 months before the accident, the mechanic failed to thoroughly inspect the brake system as required, which would have detected the corrosion and fatigue cracks prior to their ultimate failure. ## Factual narrative On October 6, 2015, about 1900 eastern daylight time, a Beech 58, N25734, sustained substantial damage when it impacted a fence while taxiing at Southwest Georgia Regional Airport (ABY), Albany, Georgia. The commercial pilot was not injured. Day visual meteorological conditions prevailed and no flight plan was filed for the local personal flight, which was conducted under the provisions of Title 14 Code of Federal Regulations Part 91. The flight originated from Dawson Municipal Airport (16J), Dawson, Georgia, around 1830.According to the pilot, the flight was uneventful. Then, while taxiing from the runway, the pilot noted "softness" when he applied the left brake. Upon entering the ramp area, he applied the brakes and attempted to slow the airplane; however, the brakes had no effect. The airplane rolled into a grass area and impacted an airport perimeter fence. According to Federal Aviation Administration records, the airplane, manufactured in 1973, was registered to a corporation in 2012. It was equipped with two Continental Motors IO-520 series, 285-hp engines. According to airplane maintenance logbooks, the most recent annual inspection was completed on March 9, 2015, and at that time, the airplane had accumulated 1,145.7 hours in-service. The maintenance log entry for the annual inspection stated that it was performed in accordance with the manufacturer guidance and the main landing gear brake linings were replaced. According to the manufacturer's guidance, item number 28 for the 100-hour inspection, stated "BRAKES – Check for condition and wear, ease of operation and proper release of the parking brake. Check for unusual brake chatter." A postaccident examination of the airplane revealed substantial damage to the left wing. At the time of the accident, the Hobbs meter indicated 1214.8 hours. In addition, the brakes were examined and there was a trace amount of hydraulic fluid in both of the brake reservoirs. Hydraulic fluid was also noted on the surface of the left wheel torque plate. Furthermore, the left wheel torque plate assembly exhibited several fractures and the fitting tube was bent. The right wheel torque plate exhibited fractures as well, and one bolt was absent from the torque plate. The main wheel torque plates and an attachment bolt from the right wheel plate were removed from the airplane and sent to the NTSB Materials laboratory for further examination. Both plates were fractured into multiple pieces and each plate contained several bolt holes, which were intersected by a fracture. Bench binocular microscope examination of each plate revealed crack arrest marks typical of fatigue cracking emanated from several bolt holes. Furthermore, the fatigue crack regions exhibited a black tint consistent with oxidation in ferrous metal. The fatigue crack terminated and regions outside the fatigue crack exhibited a rough granular texture consistent with overstress separation. The attachment bolt from the right wheel plate was fracturedon a slant plane and contained fracture features typical of overstress separation. ## Aircraft - Registration: [N25734](https://openairdocs.org/aircraft/N25734), registered now, S/N TH-390, built 1973 (OpenAirDocs) - Reported make and model: BEECH 58 - Registry model: [Beech 58](https://openairdocs.org/model/beech-58) (registry code 1152740) (OpenAirDocs) - Registry engine: [Continental IO-520 series](https://openairdocs.org/engine/continental-io-520-series) (registry code 17032, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: TH-390 - Year built: 1973 - Airframe hours: 1145.7 - Engines: CONT MOTOR IO 520 SERIES 285 horsepower reciprocating; CONT MOTOR IO 520 SERIES 285 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Rcl Farms Leasing LLC - Registered owner: Rcl Farms Leasing LLC - Airworthiness certificate: Standard, Normal - Last inspection: Annual, March 15, 2015 - Departed: 16J, DAWSON, GA - Destination: ABY, Albany, GA - Airport: ABY, Southwest Georgia Rgnl - Equipment: Unknown ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 63; injuries: none; commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, with waivers/limitations; seat: left ## Weather - Conditions: Visual (VMC), Day - Wind: 10° at 6 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 75 °F, dew point 63 °F - Altimeter: 29.97 inHg - Observed at: ABY ## 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 20151006016839A](https://openairdocs.org/incident/20151006016839A), Oct 6, 2015: Beech 58, Albany, GA, Substantial damage. On 10/06/2015 at approximately 1900 local time, pilot of Beechcraft N25734, baron B-58, landed at Albany, Georgia airport (aby) cleared onto taxiway, pilot… ## Other investigations on N25734 (1) 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. - [NTSB DEN80FA033](https://openairdocs.org/ntsb/DEN80FA033), May 16, 1980: Beech 58 (N25734), Casper, WY, substantial damage ## Docket (8 files) The files NTSB released with the investigation on March 29, 2017, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=92134. 2.9 MB in all. - Pilot Statement (item 1, .PDF, 196 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40450399&FileExtension=.PDF&FileName=Pilot%20Statement-Master.PDF - Diagram of Brake Torque Plates (item 2, .PDF, 46 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40450400&FileExtension=.PDF&FileName=Diagram%20of%20Brake%20Torque%20Plates-Master.PDF - NTSB Materials Laboratory Report - Torque Plates (item 3, .PDF, 2 photos, 271 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40450401&FileExtension=.PDF&FileName=NTSB%20Materials%20Laboratory%20Report%20-%20Torque%20Plates-Master.PDF - Most Recent Maintenance Inspection (item 4, .PDF, 173 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40450402&FileExtension=.PDF&FileName=Most%20Recent%20Maintenance%20Inspection-Master.PDF - Manufacturer's Guide - 100 Hour Inspection Excerpt (item 5, .PDF, 736 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40450403&FileExtension=.PDF&FileName=Manufacturer%27s%20Guide%20-%20100%20Hour%20Inspection%20Excerpt-Master.PDF - Weather Observations (item 6, .PDF, 122 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40450404&FileExtension=.PDF&FileName=Weather%20Observations-Master.PDF - Photos of Torque Plates on Airplane (Courtesy of FAA) (item 7, .PDF, 4 photos, 962 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40450405&FileExtension=.PDF&FileName=Photos%20of%20Torque%20Plates%20on%20Airplane%20(Courtesy%20of%20FAA)-Master.PDF - Photo Array (Courtesy of FAA) (item 8, .PDF, 2 photos, 410 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40450406&FileExtension=.PDF&FileName=Photo%20Array%20(Courtesy%20of%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.