# NTSB ERA10LA362: Garlick Helicopters OH-58A+, N802JB, Rowley, MA, July 15, 2010 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: July 15, 2010, 13:58 local (17:58 UTC) - Place: Rowley, MA - Coordinates: 42.770557, -70.874725 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=42.7706&lon=-70.8747&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering-low-alt flying: Powerplant sys/comp malf/fail](https://openairdocs.org/ntsb-events/340) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report October 17, 2011 - Report: Approved by Office Director - NTSB office: Eastern Region Aviation - Parties: JBI Helicopter Services, The Timkin Company, FAA/FSDO, Standard Aero LTD. - NTSB case key (mKey): 76652 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA10LA362 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/76652/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=76652 - Page: https://openairdocs.org/ntsb/ERA10LA362 ## Probable cause The failure of the power turbine governor internal driveshaft bearings, resulting in the failure of the governor. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Engine fuel and control: turbine governor](https://openairdocs.org/ntsb-findings/01057323): Aircraft › Aircraft power plant · Failure (probable cause); cases with it: [Garlick Helicopters OH-58A+, 1 case](https://openairdocs.org/ntsb-findings/01057323/cases.md?model=3740006), [All aircraft, 5 cases](https://openairdocs.org/ntsb-findings/01057323/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Maneuvering-low-alt flying: Powerplant sys/comp malf/fail](https://openairdocs.org/ntsb-events/340) (defining event); cases with it: [Garlick Helicopters OH-58A+, 1 case](https://openairdocs.org/ntsb-events/340/sequence.md?model=3740006), [All aircraft, 820 cases](https://openairdocs.org/ntsb-events/340/sequence.md) - [Autorotation: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Garlick Helicopters OH-58A+, 1 case](https://openairdocs.org/ntsb-events/440/sequence.md?model=3740006), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) - [Autorotation: Hard landing](https://openairdocs.org/ntsb-events/092); cases with it: [Garlick Helicopters OH-58A+, 1 case](https://openairdocs.org/ntsb-events/092/sequence.md?model=3740006), [All aircraft, 2,102 cases](https://openairdocs.org/ntsb-events/092/sequence.md) ## Analysis The pilot stated that he was conducting an aerial application flight when the low rotor rpm audio warning sounded. The pilot elected to fly the helicopter for another 30 minutes to ensure normal operation. Shortly thereafter, about 200 feet above ground level and at 70 knots, the low rotor rpm audio warning sounded again. The pilot lowered the collective to restore rotor rpm, but engine and rotor speed accelerated through the upper limits. The pilot then reduced the throttle to idle and performed an autorotation. The helicopter landed hard into a salt marsh, buckling the tail boom. The pilot did not report any flight control anomalies with the helicopter. A postaccident examination of the governor drive housing and driveshaft assemblies revealed that the inner and outer raceways were "frosted" in the ball tracks. Additionally, the ball tracks were offset from the center of the raceway in a manner consistent with a thrust load towards the driveshaft nut, relative to the drive housing. The ball track offset was not circumferentially uniform, suggesting that the bearing inner races were misaligned relative to the outer bearing races. In general, such misalignment typically results in excessive forces and subsequent fatigue failure of the ball separator. The failure of the drive bearings caused the power turbine governor to provide the incorrect signal to the main fuel control. A review of the engine records indicated that the last overhaul of the power turbine governor was at 1,942.9 hours time since new. The power turbine governor has accumulated an additional 1,590 hours time since overhaul. The power governor turbine time before overhaul (TBO) time is 2,000 hours. ## Factual narrative On July 15, 2010, at 1358 eastern daylight time, a Garlick Helicopter, OH-58A+, N802JB, registered to and operated by Horizon Helicopters LLC, experienced a hard landing in a salt marsh following a loss of the main rotor rpm control near Rowley, Massachusetts. The aerial application flight was operated under the provisions of 14 Code of Federal Regulation Part 137 with no flight plan filed. Visual meteorological conditions prevailed. The certificated commercial pilot and passenger reported no injuries, and the helicopter was substantially damaged. The flight departed Kent's Island road, Newbury, Massachusetts, at 1342. The pilot stated that he was performing an aerial application when the low rotor rpm audio warning sounded. The collective was lowered and the rpm returned to normal. The pilot elected to fly the helicopter for another 30 minutes to ensure normal operation, and the helicopter operated normally. Shortly thereafter, while in cruise flight at approximately 200 feet above ground level at 70 knots, the low rotor rpm audio warning sounded again. The collective was lowered to restore rotor rpm, but engine and rotor speed accelerated through the upper limits. The collective was then increased to load the engine and main rotor to prevent an over-speed. This attempt had no noticeable effect and, subsequently, the pilot rolled the throttle to idle, performed an autorotation, landed hard, and buckled the tail boom. The pilot did not report any flight control anomalies prior to the accident. A Federal Aviation Administration inspector examined the helicopter. Flight control continuity was confirmed from the cockpit through the tail rotor system, and from the cockpit cyclic and collective controls through the main rotor head. Further examination of the helicopter revealed that the power turbine governor was damaged, and removed for further examination. The power turbine governor was examined by representatives of the power turbine governor, bearing and engine manufacturers, under the supervision of the FAA inspector, on September 1 2010. Examination of the drive housing and drive shaft assemblies revealed that the inner and outer races were "frosted" in the ball tracks. Further examination of the driveshaft revealed that the bearing ball separators were damaged. A review of the engine records indicated that the last overhaul of the power turbine governor was completed at 1,942.9 hours time since new. The power turbine governor had accumulated an additional 1,590 hours time since overhaul. The power governor turbine time before overhaul (TBO) time is 2,000 hours. ## Aircraft - Registration: [N802JB](https://openairdocs.org/aircraft/N802JB), registered now, S/N 71-20851, built 1971 (OpenAirDocs) - Reported make and model: GARLICK HELICOPTERS INC OH-58A+ - Registry model: [Garlick Helicopters OH-58A+](https://openairdocs.org/model/garlick-helicopters-oh-58a-plus) (registry code 3740006) (OpenAirDocs) - Registry engine: [Amateur-built UNKNOWN ENG](https://openairdocs.org/engine/amateur-built-unknown-eng) (registry code 99999) (OpenAirDocs) - Category: Helicopter - Serial number: 71-20851 - Airframe hours: 7297 - Engines: Rolls Royce T63-A720 420 horsepower turbo shaft - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: Horizon Helicopters LLC, doing business as JBI Helicopter Services - Registered owner: Horizon Helicopters LLC - Airworthiness certificate: Special, Restricted (Special) - Last inspection: 100 hour, July 8, 2010, 14 hours before - Departed: Newbury, MA - Destination: 2B2, Rowley, MA - Flight plan: Unknown ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 53; injuries: none; commercial, flight instructor; airplane ratings: single-engine land, multi-engine land; instrument ratings: helicopter, airplane; medical: class 2, without waivers/limitations; last flight review January 14, 2010; seat: right; flight hours: 8,345 total, 3,395 in this make and model, 6,345 as pilot in command, 119 in the last 90 days, 45 in the last 30 days, 6 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 130° at 8 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 79 °F, dew point 68 °F - Altimeter: 30.04 inHg - Observed at: BVY, 12 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 20100715037509A](https://openairdocs.org/incident/20100715037509A), Jul 15, 2010: Garlick Hel OH-58A+, Rowley, MA, Substantial damage. The helicopter was performing aerial application when a low RPM audio came on. The pilot lowered the collective which restored RPM. Approximately 30 minutes… ## Other investigations on N802JB (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 NYC06LA224](https://openairdocs.org/ntsb/NYC06LA224), Sep 19, 2006: Garlick OH-58A (N802JB), East Bridgewate, MA, no damage. Probable cause: The completion center's installation of the incorrect (shorter) release cable, and the ground crewmember's improper movement under the flight path during a bin transfer. ## Docket (15 files) The files NTSB released with the investigation on August 24, 2011, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=76652. 10.8 MB in all. - Pilot Statement to FAA (item 1, .PDF, 97 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40352048&FileExtension=.PDF&FileName=Pilot%20Statement%20to%20FAA-Redacted.PDF - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 2, .PDF, 1.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40352049&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Other Pertinent Forms and Reports-Departure and accident times (item 3, .PDF, 11 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40349897&FileExtension=.PDF&FileName=Other%20Pertinent%20Forms%20and%20Reports-Departure%20and%20accident%20times-Master.PDF - Other Pertinent Forms and Reports-Airman proficiency check (item 4, .PDF, 193 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40346995&FileExtension=.PDF&FileName=Other%20Pertinent%20Forms%20and%20Reports-Airman%20proficiency%20check-Redacted.PDF - N802JB logbook Gov Information (item 5, .PDF, 597 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40346997&FileExtension=.PDF&FileName=N802JB%20logbook%20%20Gov%20Information-Redacted.PDF - Governor C20C Overhaul (item 6, .PDF, 957 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40346998&FileExtension=.PDF&FileName=Governor%20C20C%20Overhaul-Master.PDF - Governor PT overhaul (item 7, .PDF, 933 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40346999&FileExtension=.PDF&FileName=Governor%20PT%20overhaul-Master.PDF - JBI maintenance record status report (item 8, .PDF, 133 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40347000&FileExtension=.PDF&FileName=JBI%20maintenance%20record%20status%20report-Master.PDF - Statement of Party Representatives to NTSB Investigation-JBI (item 9, .PDF, 54 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40347004&FileExtension=.PDF&FileName=Statement%20of%20Party%20Representatives%20to%20NTSB%20Investigation-JBI-Redacted.PDF - Statement of Party Representatives to NTSB Investigation-Timkin (item 10, .PDF, 848 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40347005&FileExtension=.PDF&FileName=Statement%20of%20Party%20Representatives%20to%20NTSB%20Investigation-Timkin-Redacted.PDF - Statement of Party Representatives to NTSB Investigation-Standard Aero (item 11, .PDF, 692 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40347007&FileExtension=.PDF&FileName=Statement%20of%20Party%20Representatives%20to%20NTSB%20Investigation-Standard%20Aero-Redacted.PDF - Photo 1-operator photo-Buckled fuselage (item 12, .PDF, 1.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40352050&FileExtension=.PDF&FileName=Photo%201-operator%20photo-Buckled%20fuselage-Master.PDF - photo 2-operator photo-Buckled tail boom (item 13, .PDF, 1.4 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40352051&FileExtension=.PDF&FileName=photo%202-operator%20photo-Buckled%20tail%20boom-Master.PDF - Photo 3-operator photo-Front view helicopter (item 14, .PDF, 1.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40352052&FileExtension=.PDF&FileName=Photo%203-operator%20photo-Front%20view%20helicopter-Master.PDF - Photo 4-operator photo-Governor and driveshaft (item 15, .PDF, 1.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40352053&FileExtension=.PDF&FileName=Photo%204-operator%20photo-Governor%20and%20driveshaft-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.