# NTSB LAX01LA079: Hughes 369D, N8353F, Ely, NV, January 23, 2001 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: January 23, 2001, 07:45 local (15:45 UTC) - Place: Ely, NV - Coordinates: 39.247161, -114.86769 - Nearby events: https://openairdocs.org/map.md?lat=39.2472&lon=-114.8677&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 4 uninjured - Status: Completed, report March 30, 2004 - Report: Approved by Office Director - Parties: Federal Aviation Administration - NTSB case key (mKey): 51383 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX01LA079 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/51383/pdf - Page: https://openairdocs.org/ntsb/LAX01LA079 ## Probable cause The mechanic's inadvertent activation of the bleed valve, which resulted in a loss of engine oil and loss of engine power while in cruise flight. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(total) - mech failure/malf, cruise - acft/equip inadequate,equipment interference, manufacturer - lubricating system,oil quickdrain/drain plug - activated (cause) - maintenance,replacement - improper, company maintenance personnel (cause) - fluid,oil - leak (cause) - fluid,oil - exhaustion (cause) - Forced landing, emergency descent/landing - autorotation - performed, pilot in command - Miscellaneous/other, landing - flare/touchdown - misc rotorcraft,main rotor/tail boom contact ## Analysis The single engine helicopter experienced a loss of engine power after the oil was inadvertently pumped overboard. A company mechanic replaced the torque gauge prior to the accident flight due to needle "bounce." The mechanic bled the torque system and reinstalled a radio that was removed to facilitate the work. During the radio installation, he inadvertently engaged the bleed valve, which is located behind the instrument panel, allowing oil to flow out of the engine from behind the instrument panel. While at 9,500 feet, the engine lost power and the pilot performed an autorotation landing to a field at the base of mountains. The pilot said he touched down smooth and light; however, the main rotor blades flexed and severed the tail boom. As a result of the accident, the operator rerouted the torque system bleed line toward the pilot's feet so that they could detect an inadvertent oil leak. ## Factual narrative On January 23, 2001, approximately 0745 Pacific standard time, a Hughes 369D single-engine helicopter, N8353F, impacted terrain during an autorotation landing following a loss of engine power while in cruise flight near Ely, Nevada. The helicopter was registered to and operated by Hawkins & Powers Aviation, Inc., Greybull, Wyoming, under the provisions of 14 CFR Part 91 as a business flight. The helicopter sustained substantial damage, and the commercial pilot and three passengers were not injured. The business flight departed Ely about 0730, and was destined for private property near Ely. Visual meteorological conditions prevailed, and a company flight plan had been filed. According to the pilot's written statement, the torque gauge was showing a "bounce" in its reading. The pilot notified a company mechanic, who elected to replace the torque gauge with a new one. The mechanic replaced the torque gauge and bled the system at the torque gauge bleed valve behind the instrument panel. He removed the radio located below the torque gauge to facilitate the work. He tested the system, noted no leaks, and replaced the radio. The flight departed to ferry company personnel to a job site. Approximately 1.5 miles from the planned destination, the pilot noticed the needle "bounce" on the torque gauge, and illumination of the "engine chip" caution light. The pilot notified his passengers and told them that they would be landing early. Approximately 30 seconds after noticing the chip light, at an elevation of 9,500 feet, the engine lost power. The pilot entered an autorotation and attempted to land at the base of mountains at the 7,500-foot level. The pilot stated the helicopter touched down "very smooth and light;" however, during the landing roll, the main rotor blades flexed down and severed the tail boom. According to the operator, the bleed valve is located in a confined area behind the instrument panel. When the mechanic conducted the system bleed, and reinstalled the radio, he inadvertently hit the bleed valve. Oil seeped out of the engine through the bleed valve and down behind the instrument console. Examination of the engine after the accident revealed it had no oil, and metal covered the upper chip detector. The bottom of the helicopter was coated with oil. ## Aircraft - Registration: [N8353F](https://openairdocs.org/aircraft/N8353F), registered now, S/N 1260062D, built 1977 (OpenAirDocs) - Reported make and model: Hughes 369D - 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: 1260062D - Airframe hours: 11037.7 - Engines: Allison 250-C20-B 420 horsepower turbo shaft - Damage: Substantial damage - Flight: Business, Part 91 - Registered owner: Hawkins and Powers Aviation, Inc. - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, January 2, 2001, 47.5 hours before - Departed: ELY, Ely, NV - Destination: Ely, NV - Flight plan: Company VFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 48; injuries: none; commercial; airplane ratings: single-engine land; instrument ratings: helicopter, airplane; medical: class 2, valid medical--w/ waivers/lim; last flight review November 6, 2000; seat: left; flight hours: 11,460 total, 764 in this make and model, 10,930 as pilot in command, 45 in the last 90 days, 32 in the last 30 days, 6 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 170° at 9 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 18 °F, dew point 16 °F - Altimeter: 30.17 inHg - Observed at: Ely, 15 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 20010123000819A](https://openairdocs.org/incident/20010123000819A), Jan 23, 2001: Hughes 369D, Ely, NV, No damage. (-23) On 1/23/01, about 0745 PST, N8353F sustained damage during a hard landing (off airport) after the engine quit during an autorotation. The main rotor… ## Other investigations on N8353F (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 SEA02TA067](https://openairdocs.org/ntsb/SEA02TA067), Apr 11, 2002: Hughes 369D (N8353F), Richland, WA, substantial damage. Probable cause: Failure of the netting material securing a net weight while maneuvering. The net weight was a factor. 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.