# NTSB ANC13LA074: Hughes 500D, N134SH, Delta Junction, AK, August 6, 2013 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 3 · Limited · Final report - Date: August 5, 2013, 18:05 local (Aug 6, 2013, 02:05 UTC) - Place: Delta Junction, AK - Coordinates: 64.046669, -145.69555 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=64.0467&lon=-145.6955&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering-hover: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Alaska Regional Office - Parties: Soloy Helicopters, Inc., Rolls Royce Corporation, Federal Aviation Administration, Boeing Helicopters, MD HELICOPTERS - NTSB case key (mKey): 87693 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC13LA074 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/87693/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=87693 - Page: https://openairdocs.org/ntsb/ANC13LA074 ## Probable cause A total loss of engine power for undetermined reasons, which necessitated an emergency hovering autorotation, during which the helicopter impacted trees and terrain. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Not determined](https://openairdocs.org/ntsb-findings/05000000): Not determined › Not determined · Unknown/Not determined (probable cause); cases with it: [Hughes Helicopters HUGHES 369D, 8 cases](https://openairdocs.org/ntsb-findings/05000000/cases.md?model=4470706), [All aircraft, 2,247 cases](https://openairdocs.org/ntsb-findings/05000000/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Maneuvering-hover: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) (defining event); cases with it: [Hughes Helicopters HUGHES 369D, 12 cases](https://openairdocs.org/ntsb-events/341/sequence.md?model=4470706), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md) - [Emergency descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Hughes Helicopters HUGHES 369D, 26 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=4470706), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The pilot was transporting sections of water hose to a remote site via a 100-ft-long external load line that was attached to the helicopter’s belly-mounted cargo hook. While the helicopter was hovering about 100 ft over the intended site and about 5 to 10 ft above trees while facing into a hill, the engine lost all power. The pilot then initiated an emergency hovering autorotation and turned the helicopter left in an attempt to face it downhill. Subsequently, the helicopter settled into trees, during which the main rotor blades impacted several of them, followed by it impacting terrain hard and rolling onto its right side, which resulted in substantial damage to the main rotor drive system, tailboom, and fuselage. During a postaccident examination, about 60 lbs of fuel were drained from the helicopter’s fuel cell; thus, fuel exhaustion did not cause the loss of power. During an engine test-run, the engine produced full-rated power at various power settings. Postaccident examination of the helicopter revealed no preaccident mechanical malfunctions or failures that would have precluded normal operation. Based on the available information, the reason for the loss of engine power could not be determined. ## Factual narrative On August 5, 2013, about 1800 Alaska daylight time, a McDonnell Douglas/Hughes 500D helicopter, N134SH, was substantially damaged when it was involved in an accident near Delta Junction, Alaska. The pilot was not injured. The helicopter was being operated as a Title 14 Code of Federal Regulations Part 133 external load flight. The pilot was transporting sections of water hose to a remote site via a 100-ft-long external load line attached to the helicopter’s belly-mounted cargo hook. The pilot reported that while the helicopter was hovering about 100 ft over the intended site and about 5 to 10 ft above trees while facing into a hill, the engine lost all power. He then initiated an emergency hovering autorotation and turned the helicopter left in an attempt to face it downhill. Subsequently, the helicopter settled into trees, during which the main rotor blades struck several of them, followed by it impacting terrain hard and then rolling onto its right side, which resulted in substantial damage to the main rotor drive system, tailboom, and fuselage. During postaccident examination, about 60 lbs of fuel, 47 lbs of which were usable, were drained from the helicopter’s fuel cell. During an engine test-run, the engine produced full rated power at various power settings. During a subsequent test-run, the electric fuel pump operated within its operating specifications. Examination of the fuel pump revealed that the motor commutator and brushes exhibited wear. Postaccident examination of the helicopter revealed no preaccident mechanical malfunctions or failures that would have precluded normal operation. ## Aircraft - Registration: [N134SH](https://openairdocs.org/deregistered/N134SH-2014-12-12), registration cancelled 2014-12-12, S/N 610969D, built 1981 (OpenAirDocs) - Reported make and model: HUGHES 500D - Registry model: [Hughes Helicopters HUGHES 369D](https://openairdocs.org/model/hughes-helicopters-hughes-369d) (registry code 4470706) (OpenAirDocs) - Registry engine: [Rolls-Royce 250-C20B](https://openairdocs.org/engine/rolls-royce-250-c20b) (registry code 54385, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: 610969D - Airframe hours: 9807 - Engines: Rolls Royce M250-C20B 420 horsepower turbo shaft - Damage: Substantial damage - Flight: External load, Part 133 - Operator: Soloy Helicopters LLC - Registered owner: Wells Fargo Bank NW - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, July 30, 2013 - Departed: Delta Junction, AK - Destination: Delta Junction, AK - Flight plan: Company VFR - Equipment: None ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 65; injuries: none; airline transport; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane, helicopter; medical: class 1, with waivers/limitations; seat: left; restraint: 4-point; flight hours: 19,000 total, 4,000 in this make and model, 202 in the last 90 days, 50 in the last 30 days, 8 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 190° at 9 knots - Visibility: 10 statute miles - Lowest ceiling: 20,000 ft broken - Temperature: 73 °F, dew point 37 °F - Altimeter: 29.89 inHg - Observed at: PABI ## 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 20130805016129A](https://openairdocs.org/incident/20130805016129A), Aug 5, 2013: Hughes 369D, Delta Junction, AK, Substantial damage. The pilot was conducting a 14 CFR part 133 class c operation when the engine on the helicopter abruptly stopped. The pilot had to autorotate into the trees.… ## Docket (6 files) The files NTSB released with the investigation on December 31, 2020, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=87693. 19.2 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 9 pages, 771 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11567844&FileExtension=pdf&FileName=point%20one_Redacted-Rel.pdf - Witness statements (item 2, PDF, 5 pages, 3.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11569139&FileExtension=pdf&FileName=ANC13LA074%20Witness%20Statments_Redacted-Rel.pdf - Record of conversation (item 3, PDF, 1 page, 47 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11569511&FileExtension=pdf&FileName=ANC13LA074%20Record%20of%20Conversation-Rel.pdf - Fuel pump examination (item 4, PDF, 65 pages, 6.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11569329&FileExtension=pdf&FileName=Fuel%20Pump%20Test_Redacted-Rel.pdf - Statement of party representatives to NTSB investigation (item 5, PDF, 4 pages, 6.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11569001&FileExtension=pdf&FileName=ANC13LA074%20Party%20Forms_Redacted-Rel.pdf - Accident images (item 6, PDF, 2 pages, 2.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11568756&FileExtension=pdf&FileName=Accident%20Images-Rel.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.