# NTSB GAA16LA182: Hughes 369, N298SD, Weatherford, TX, April 8, 2016 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: April 8, 2016, 09:30 local (14:30 UTC) - Place: Weatherford, TX - Coordinates: 32.771389, -97.73944 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=32.7714&lon=-97.7394&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Defining event: [Takeoff: Flight control sys malf/fail](https://openairdocs.org/ntsb-events/333) - Highest injury: Serious injuries - Injuries: 1 serious - Status: Completed, report January 18, 2017 - Report: Approved by Office Director - NTSB office: General Aviation Accidents - Parties: FAA North Texas FSDO - NTSB case key (mKey): 92985 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=GAA16LA182 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/92985/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=92985 - Page: https://openairdocs.org/ntsb/GAA16LA182 ## Probable cause The pilot/mechanic's inadequate postmaintenance and preflight inspections, which resulted in his failure to remove the antitorque pedal lock and a subsequent loss of control during hover operations. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Inspection: preflight inspection](https://openairdocs.org/ntsb-findings/02061510): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Hughes 369A, 3 cases](https://openairdocs.org/ntsb-findings/02061510/cases.md?model=4470503), [All aircraft, 551 cases](https://openairdocs.org/ntsb-findings/02061510/cases.md) - [Inspection: post maintenance inspection](https://openairdocs.org/ntsb-findings/02061515): Personnel issues › Task performance · Maintenance personnel (probable cause); cases with it: [Hughes 369A, 1 case](https://openairdocs.org/ntsb-findings/02061515/cases.md?model=4470503), [All aircraft, 57 cases](https://openairdocs.org/ntsb-findings/02061515/cases.md) - [Rotorcraft flight control: tail rotor control system](https://openairdocs.org/ntsb-findings/01046720): Aircraft › Aircraft propeller/rotor · Inadequate inspection (probable cause); cases with it: [Hughes 369A, 2 cases](https://openairdocs.org/ntsb-findings/01046720/cases.md?model=4470503), [All aircraft, 13 cases](https://openairdocs.org/ntsb-findings/01046720/cases.md) - [Object/animal/substance: tree(s)](https://openairdocs.org/ntsb-findings/03022020): Environmental issues › Physical environment · Contributed to outcome; cases with it: [Hughes 369A, 2 cases](https://openairdocs.org/ntsb-findings/03022020/cases.md?model=4470503), [All aircraft, 933 cases](https://openairdocs.org/ntsb-findings/03022020/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: [Hughes 369A, 1 case](https://openairdocs.org/ntsb-events/040/sequence.md?model=4470503), [All aircraft, 484 cases](https://openairdocs.org/ntsb-events/040/sequence.md) - [Prior to flight: Aircraft inspection event](https://openairdocs.org/ntsb-events/050); cases with it: [Hughes 369A, 1 case](https://openairdocs.org/ntsb-events/050/sequence.md?model=4470503), [All aircraft, 229 cases](https://openairdocs.org/ntsb-events/050/sequence.md) - [Takeoff: Flight control sys malf/fail](https://openairdocs.org/ntsb-events/333) (defining event); cases with it: [Hughes 369A, 1 case](https://openairdocs.org/ntsb-events/333/sequence.md?model=4470503), [All aircraft, 410 cases](https://openairdocs.org/ntsb-events/333/sequence.md) - [Takeoff: Loss of control in flight](https://openairdocs.org/ntsb-events/240); cases with it: [Hughes 369A, 2 cases](https://openairdocs.org/ntsb-events/240/sequence.md?model=4470503), [All aircraft, 5,002 cases](https://openairdocs.org/ntsb-events/240/sequence.md) - [Takeoff: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Hughes 369A, 3 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=4470503), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The pilot/mechanic stated that, while performing maintenance on the helicopter, he locked the left side antitorque (tail rotor) pedals to keep them out of the way; however, he forgot to unlock them after completing the maintenance. The pilot then conducted a post-maintenance hover check, and, upon increasing collective, the helicopter entered a spin, traveled about 40 feet, and collided with a building and trees. The pilot stated that there were no preimpact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation, and that the accident was the result of his failure to remove the antitorque pedal lock before flight. ## Factual narrative On April 8, 2016, about 0930 central daylight time, a MD Helicopters (formerly Hughes) 369A helicopter, N298SD, collided with a building and trees during takeoff at the Staggs Heliport (TE93), Weatherford, Texas. The commercial pilot/airframe and power plant mechanic sustained serious injuries, and the helicopter sustained substantial damage. The helicopter was registered to, and operated by the pilot as a day, visual flight rules (VFR) flight under the provisions of 14 Code of Federal Regulations Part 91 as a maintenance check flight. Visual meteorological conditions prevailed and no flight plan was filed. The flight originated from the Staggs Heliport (TE93), about 0930. The pilot/mechanic submitted a written statement to the National Transportation Safety Board (NTSB) investigator-in-charge (IIC) on April 30, and stated that during a battery installation on the helicopter, he "locked" the left side anti-torque (tail rotor) pedals in the cockpit to keep them out of the way during the battery installation and forgot to "unlock" them. While conducting a powered maintenance check after an engine installation on the ground, he stated that he was checking the governor and had his seat restraint system on in the right seat for when he "goes to the top end." He stated that he "pulled collective to check at a hover" and the helicopter departed the ground, spun several times, traveled about 40 feet, and collided with a building and trees. The pilot/mechanic sustained serious injuries from the accident sequence. The pilot/mechanic further stated that this was a maintenance error. The helicopter sustained substantial damage to the main rotor system, the fuselage, the tailboom, and the tail rotor system. The pilot/mechanic verified that there were no preimpact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation. AIRCRAFT INFORMATION The accident helicopter was originally manufactured as an OH-6A for the US Army. After the completion of service with the US Army, the helicopter was issued a standard airworthiness certificate by the Federal Aviation Administration (FAA). WRECKAGE AND IMPACT INFORMATION The photographs of the wreckage supplied by the FAA aviation safety inspector (ASI) showed that the helicopter came to rest with its left side against a small group of trees in close proximity to a residential building and both of the skids had collapsed. Three of the four main rotor blades exhibited several bends at various locations through the length of the blades due to impacting the trees and building while one main rotor blade separated at the blade root. The bottom of the fuselage exhibited crushing consistent with a downward impact with terrain and the tailboom was bent at about the midpoint between the tail rotor and the fuselage. The tailboom was also crushed inward on the left side, just forward of the tail rotor system. The lower vertical fin displayed impact damage on the lower left side.Inside the cockpit, the anti-torque pedals on the right side were observed with the left anti-torque pedal positioned in place with an adjustment pin installed at the top of the pedal arm and the right anti-torque pedal was also positioned in place but did not have an adjustment pin installed at the top of the pedal arm. On the left side of the cockpit, the left anti-torque pedal was displaced from the pedal arm and lying against the center console with the adjustment pin missing and the right anti-torque pedal was positioned in place with an adjustment pin installed at the top of the pedal arm. The center section of the right side cockpit windshield was punctured during the accident sequence. On the right side of the cockpit, the FAA ASI reported that underneath the floor board was various mechanic tools. He further reported that it appears that this foreign object debris did not contribute to the accident. ADDITIONAL INFORMATION Preflight Checklist Excerpts from the US Army Operators Manual Helicopter Observation OH-6A TM 55-1520-214-10 (1976) for the preflight checklist are available in the public docket for this accident. Anti-Torque Control System Excerpts from the US Army Operators Manual Helicopter Observation OH-6A TM 55-1520-214-10 (1976) for the anti-torque control system are available in the public docket for this accident. MD Helicopters Service Letter SL369H-124R3 MD Helicopters has published Service Letter SL369H-124R3 (2004). This document describes the maintenance and operation requirements of surplus 369A (OH-6A) series helicopters and states in part: Failure to comply with established FAA regulations, airworthiness directives, mandatory retirement, overhaul life limits, and proper inspection and maintenance procedures may lead to loss of control of the helicopter and subsequent injury, death and/or property damage. ## Aircraft - Registration: [N298SD](https://openairdocs.org/aircraft/N298SD), registered now, S/N 280332, built 1968 (OpenAirDocs) - Reported make and model: HUGHES 369 (A) - Registry model: [Hughes 369A](https://openairdocs.org/model/hughes-369a) (registry code 4470503) (OpenAirDocs) - Registry engine: [Allison 250-C10D](https://openairdocs.org/engine/allison-250-c10d) (registry code 03035, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: 280332 - Year built: 1968 - Airframe hours: 4195 - Engines: Rolls-Royce Corporation 250-C10B 250 horsepower turbo shaft - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, February 14, 2016 - Departed: TE93, Weatherford, TX - Destination: TE93, Weatherford, TX - Airport: TE93, Staggs - Equipment: None ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 67; injuries: serious; commercial; airplane ratings: multi-engine land, single-engine land; medical: class 2, with waivers/limitations; last flight review May 18, 2014; seat: right; restraint: 3-point; flight hours: 649 total, 11 in this make and model, 601 as pilot in command, 11 in the last 90 days ## Weather - Conditions: Visual (VMC), Day - Wind: 80° at 12 knots - Visibility: 10 statute miles - Lowest ceiling: 25,000 ft broken - Temperature: 66 °F, dew point 25 °F - Altimeter: 30.20 inHg - Observed at: KNFW, 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 20160408008779A](https://openairdocs.org/incident/20160408008779A), Apr 8, 2016: Hughes 369A, Weatherford, TX, Substantial damage. The pilot stated that he locked the tail rotor peddles on the left side when he hooked up the battery following maintenance. He forgot to unhook the peddles.… ## Other investigations on N298SD (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 CEN09CA332](https://openairdocs.org/ntsb/CEN09CA332), May 30, 2009: Hughes 369A (N298SD), Baltimore, OH, substantial damage. Probable cause: The pilot's failure to attain a proper touchdown point, and his decision not to perform a go-around. ## Docket (7 files) The files NTSB released with the investigation on November 2, 2016, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=92985. 6.5 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 2.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40446036&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Accident Photographs (item 2, .PDF, 3.4 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40446037&FileExtension=.PDF&FileName=Accident%20Photographs%20-Master.PDF - Record of Conversation FAA (item 3, .PDF, 118 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40446038&FileExtension=.PDF&FileName=Record%20of%20Conversation%20FAA-Master.PDF - Record of Conversation Pilot (item 4, .PDF, 117 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40446039&FileExtension=.PDF&FileName=Record%20of%20Conversation%20Pilot-Master.PDF - TM 55-1520-214-10 Antitorque Control System (item 5, .PDF, 171 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40446040&FileExtension=.PDF&FileName=TM%2055-1520-214-10%20Antitorque%20Control%20System-Master.PDF - TM 55-1520-214-10 Operating Procedures (item 6, .PDF, 635 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40446041&FileExtension=.PDF&FileName=TM%2055-1520-214-10%20Operating%20Procedures-Master.PDF - MD Helicopters Service Letter SL369H-124R3 (item 7, .PDF, 53 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40446042&FileExtension=.PDF&FileName=MD%20Helicopters%20Service%20Letter%20SL369H-124R3-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.