# NTSB CEN09IA618: Bell 230, N880SF, Peoria, IL, July 1, 2009 - Type: NTSB incident investigation - Classification: Incident · No injuries · Incident investigation · Final report - Date: July 1, 2009, 18:15 local (23:15 UTC) - Place: Peoria, IL - Coordinates: 40.664165, -89.693054 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=40.6642&lon=-89.6931&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute: Sys/Comp malf/fail (non-power)](https://openairdocs.org/ntsb-events/330) - Highest injury: No injuries - Injuries: 4 uninjured - Status: Completed, report November 17, 2011 - Report: Approved by Office Director - NTSB office: Central Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 78143 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN09IA618 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/78143/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=78143 - Page: https://openairdocs.org/ntsb/CEN09IA618 ## Probable cause The loss of the number one hydraulic system fluid and hydraulic pressure during cruise due to the failure of the bolts that secure the hydraulic pump's cover. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Hydraulic power system: pump, main](https://openairdocs.org/ntsb-findings/01022913): Aircraft › Aircraft systems · Failure (probable cause); cases with it: [Bell 230, 1 case](https://openairdocs.org/ntsb-findings/01022913/cases.md?model=1182149), [All aircraft, 7 cases](https://openairdocs.org/ntsb-findings/01022913/cases.md) - [Fluids: hydraulic fluid](https://openairdocs.org/ntsb-findings/01071015): Aircraft › Fluids/misc hardware · Fluid level (probable cause); cases with it: [Bell 230, 1 case](https://openairdocs.org/ntsb-findings/01071015/cases.md?model=1182149), [All aircraft, 33 cases](https://openairdocs.org/ntsb-findings/01071015/cases.md) - [Misc hardware: fasteners](https://openairdocs.org/ntsb-findings/01071430): Aircraft › Fluids/misc hardware · Not specified (probable cause); cases with it: [Bell 230, 1 case](https://openairdocs.org/ntsb-findings/01071430/cases.md?model=1182149), [All aircraft, 58 cases](https://openairdocs.org/ntsb-findings/01071430/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute: Sys/Comp malf/fail (non-power)](https://openairdocs.org/ntsb-events/330) (defining event); cases with it: [Bell 230, 1 case](https://openairdocs.org/ntsb-events/330/sequence.md?model=1182149), [All aircraft, 994 cases](https://openairdocs.org/ntsb-events/330/sequence.md) - [Landing: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Bell 230, 1 case](https://openairdocs.org/ntsb-events/440/sequence.md?model=1182149), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) ## Analysis The helicopter pilot observed a caution light for the number one hydraulic system and a corresponding complete loss of hydraulic system pressure for that system. The pilot declared an emergency and performed a run-on landing. A postincident examination of the system's hydraulic pump revealed that two of its cover attachment bolts had separated. The bolt heads fractured in tension from their shanks via intergranular cracks which initiated at the filet radius between the bead and the shank. The bolt fractures exhibited intergranular fracture features over 90 percent of the surface. The operator’s incident report safety recommendation stated that the pump's cover bolts should be replaced at overhaul; however, it is not required. The helicopter had accumulated 269 hours since overhaul. ## Factual narrative On July 1, 2009, at 1815 central daylight time, a Bell 230 helicopter, N880SF, sustained no damage during a forced landing at the General Downing - Peoria International Airport (PIA), near Peoria, Illinois, after it lost fluid in its number one hydraulic system during cruise flight. The commercial helicopter pilot, two emergency medical services (EMS) crewmembers, and the patient were not injured. Visual meteorological conditions prevailed and no flight plan was filed. The local non-scheduled domestic 14 Code of Federal Regulations Part 135 EMS transport flight departed PIA at time unknown. According to the operator’s incident report, the pilot observed a caution light for the number one hydraulic system and a corresponding complete loss of hydraulic system pressure for that system. The pilot declared an emergency and performed a run-on landing. Examination of the system's hydraulic pump revealed that two of its cover attachment bolts had separated. The separated bolt heads were retained by safety wire. This hydraulic pump manufacturer’s part number was 65132-1. The Bell Helicopter part number is 222-380-009-105, which is also usable on the Bell 222 series and 430 model helicopters. The bolts that sustained the separation were part number MS24678-17. According to the helicopter manufacturer, these hydraulic pumps do not have a scheduled overhaul cycle and the pumps are replaced on-condition. The manufacturer does not track the service times of these pumps. Reportedly, this was the first failure of the hydraulic pump cover attachment bolts. The pump manufacturer had the failed bolts examined. The bolt heads fractured in tension from their shanks via intergranular cracks initiating at the filet radius between the bead and the shank. The bolt fractures exhibited intergranular fracture features over 90 percent of the surface. According to the operator, the incident pump accumulated 269 hours of time prior to the bolt failures. The operator’s incident report safety recommendation indicated, “Recommend pump cover bolts be replaced at overhaul.” ## Aircraft - Registration: [N880SF](https://openairdocs.org/aircraft/N880SF), registered now, S/N 23024 (OpenAirDocs) - Reported make and model: BELL 230 - Registry model: [Bell 230](https://openairdocs.org/model/bell-230) (registry code 1182149) (OpenAirDocs) - Category: Helicopter - Serial number: 23024 - Airframe hours: 5673 - Engines: Rolls Royce C30 G/2 turbo shaft; Rolls Royce C30 G/2 turbo shaft - Damage: No damage - Flight: Part 135 - Operator: Osf Aviation LLC - Registered owner: Osf Aviation LLC - Airworthiness certificate: Standard, Transport - Departed: PIA, Peoria, IL - Destination: PIA, Peoria, IL - Flight plan: Unknown - Airport: PIA, General Downing - Peoria IAP ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 46; injuries: none; commercial; airplane ratings: single-engine land; instrument ratings: helicopter; medical: class 2, with waivers/limitations; seat: right; flight hours: 7,100 total, 865 in this make and model ## Weather - Conditions: Visual (VMC) - Observed at: PIA ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Incident 20090701020029I](https://openairdocs.org/incident/20090701020029I), Jul 1, 2009: Bell 230, Peoria, IL, No damage. Pilot reported a hydraulic system failure and declared and emergency. The aircraft landed without incident at Peoria, IL (pia). This incident is closed with… ## Other investigations on N880SF (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 CHI03IA293](https://openairdocs.org/ntsb/CHI03IA293), Aug 20, 2003: Bell 230 (N880SF), Wilmington, IL, incident, minor damage. Probable cause: The material defect during the manufacture of the tail rotor counterweight bellcrank and the bellcrank's subsequent failure due to a fatigue fracture. ## Docket (5 files) The files NTSB released with the investigation on September 30, 2011, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=78143. 2.3 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 1.7 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40347960&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Miscellaneous - Operator's Quality Alert Notice (item 2, .PDF, 126 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40347950&FileExtension=.PDF&FileName=Miscellaneous%20-%20Operator%27s%20Quality%20Alert%20Notice-Redacted.PDF - Correspondence - Helicopter Manufacturer's Communication (item 3, .PDF, 73 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40354589&FileExtension=.PDF&FileName=Correspondence%20-%20Helicopter%20Manufacturer%27s%20Communication-Master.PDF - Other Pertinent Forms and Reports - Manufacturer's Metallurgical Laboratory Investigation Report/Data (item 4, .PDF, 361 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40347951&FileExtension=.PDF&FileName=Other%20Pertinent%20Forms%20and%20Reports%20-%20Manufacturer%27s%20Metallurgical%20Laboratory%20Investigation%20Report%2FData-Master.PDF - Other Pertinent Forms and Reports - Weather Report for Peoria, IL (item 5, .PDF, 25 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40347992&FileExtension=.PDF&FileName=Other%20Pertinent%20Forms%20and%20Reports%20-%20Weather%20Report%20for%20Peoria,%20IL-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.