# NTSB CEN14LA465: Bell 206B, N866H, Spring, TX, July 30, 2014 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: July 30, 2014, 10:30 local (15:30 UTC) - Place: Spring, TX - Coordinates: 30.061944, -95.55278 - Nearby events: https://openairdocs.org/map.md?lat=30.0619&lon=-95.5528&mi=10 - Phase of flight: [Standing](https://openairdocs.org/ntsb-phases/150) (OpenAirDocs' grouping) - Defining event: [Standing-engine(s) start-up: Miscellaneous/other](https://openairdocs.org/ntsb-events/900) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report January 14, 2015 - Report: Approved by Office Director - NTSB office: Central Region - Parties: FAA Houston FSDO - NTSB case key (mKey): 89977 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN14LA465 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/89977/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=89977 - Page: https://openairdocs.org/ntsb/CEN14LA465 ## Probable cause The pilot's distraction by a cell phone call, which led to his failure to perform an exterior check of the helicopter and resulted in a tie-down strap remaining attached to the main rotor during the engine start. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Attention/monitoring: task monitoring/vigilance](https://openairdocs.org/ntsb-findings/02021520): Personnel issues › Psychological · Pilot (probable cause); cases with it: [Bell 206B, 7 cases](https://openairdocs.org/ntsb-findings/02021520/cases.md?model=1181511), [All aircraft, 330 cases](https://openairdocs.org/ntsb-findings/02021520/cases.md) - [Main rotor system](https://openairdocs.org/ntsb-findings/01046200): Aircraft › Aircraft propeller/rotor · Not specified; cases with it: [Bell 206B, 1 case](https://openairdocs.org/ntsb-findings/01046200/cases.md?model=1181511), [All aircraft, 25 cases](https://openairdocs.org/ntsb-findings/01046200/cases.md) - [Tail rotor: tail rotor blade](https://openairdocs.org/ntsb-findings/01046410): Aircraft › Aircraft propeller/rotor · Not specified; cases with it: [Bell 206B, 2 cases](https://openairdocs.org/ntsb-findings/01046410/cases.md?model=1181511), [All aircraft, 31 cases](https://openairdocs.org/ntsb-findings/01046410/cases.md) - [Inspection](https://openairdocs.org/ntsb-findings/02061500): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Bell 206B, 1 case](https://openairdocs.org/ntsb-findings/02061500/cases.md?model=1181511), [All aircraft, 29 cases](https://openairdocs.org/ntsb-findings/02061500/cases.md) - [Action: forgotten action/omission](https://openairdocs.org/ntsb-findings/02041035): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Bell 206B, 4 cases](https://openairdocs.org/ntsb-findings/02041035/cases.md?model=1181511), [All aircraft, 440 cases](https://openairdocs.org/ntsb-findings/02041035/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Standing-engine(s) start-up: Miscellaneous/other](https://openairdocs.org/ntsb-events/900) (defining event); cases with it: [Bell 206B, 10 cases](https://openairdocs.org/ntsb-events/900/sequence.md?model=1181511), [All aircraft, 1,556 cases](https://openairdocs.org/ntsb-events/900/sequence.md) ## Analysis The pilot reported that he completed the preflight inspection of the helicopter while it was still in the hangar and that it was then moved onto the ramp. When the pilot arrived to start the helicopter, he was distracted by a cell phone call and did not perform an exterior check of the helicopter. The main rotor tie-down was still attached to the main rotor when the pilot engaged the engine. He was monitoring the cockpit gauges during the engine start when he noticed an individual approaching the helicopter waving his hands. He then heard a "thump," and he initiated an emergency shutdown. He reported no preaccident mechanical malfunctions or failures with the helicopter that would have precluded normal operation. The examination of the helicopter revealed that the tie-down strap had broken during the engine start and had gotten caught on the tail rotor output shaft, which resulted in substantial damage to the tail boom, tail rotor blades, and vertical fin. ## Factual narrative On July 30, 2014, about 1030 central daylight time, a Bell 206B, N866H, sustained substantial damage during engine start-up at the David Wayne Hooks Airport (DWH), Spring, Texas. The pilot was not injured. The helicopter was owned by Helicopter Services Inc. and operated by the Harris County Sheriff's Office as a local public aircraft flight. Visual meteorological conditions prevailed at the time of the accident. No flight plan was filed. The helicopter was departing on a local flight. The pilot reported that he completed the preflight of the helicopter while it was still in the hangar, after which time the helicopter was moved onto the ramp. When the pilot arrived to start the helicopter, he was distracted by a phone call on his cellular phone and did not do an exterior check of the helicopter. The main rotor tie-down was still attached when the pilot engaged the engine. He was monitoring the cockpit gauges during the engine start when he noticed another officer approaching the helicopter waving his hands. He heard a "thump" and he initiated an emergency shutdown. The pilot stated that the engine start was aborted at 15 percent N1 (compressor speed), 25 percent N2 (power turbine speed), rotor rpm was less than 20 percent NR (main rotor rpm), and the TOT (turbine outlet temperature) did not exceed startup limits. He reported that there was no malfunction or system failure of the helicopter before the accident. The examination of the helicopter revealed that the tie-down strap had broken during the engine start and became caught on the tail rotor output shaft. The strap hit the tail boom and dented and gouged about the last two feet of the tail boom which required the skin to be replaced. The main rotor blade tip cap pulled loose. The main rotor blades were still serviceable, but they were replaced because they were 120 hours from the required replacement interval. The tail rotor blades were dented beyond limits and were replaced. The vertical fin was gouged; and although the honeycomb panel was repairable, the vertical fin was replaced instead of waiting for it to be overhauled. The tail rotor gearbox, the tail rotor hub, and the freewheeling unit needed to be inspected for sudden stoppage, which resulted in the units being overhauled. It was determined that the aggregate damage would affect the structural strength or performance of the helicopter and required major repair or replacement; therefore it was considered substantial damage. ## Aircraft - Registration: [N866H](https://openairdocs.org/aircraft/N866H), registered now, S/N 3291, built 1981 (OpenAirDocs) - Reported make and model: BELL 206B - Registry model: [Bell 206B](https://openairdocs.org/model/bell-206b) (registry code 1181511) (OpenAirDocs) - Registry engine: [Allison 250 SER 317HP](https://openairdocs.org/engine/allison-250-ser-317hp) (registry code 03011, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: 3291 - Year built: 1981 - Airframe hours: 7247 - Engines: Rolls-Royce C20B 420 horsepower turbo shaft - Damage: Substantial damage - Flight: Public aircraft - local, Public use - Operator: Harris County Sheriff's Office - Registered owner: Helicopter Services Inc - Airworthiness certificate: Standard, Normal - Last inspection: Annual, December 16, 2013 - Departed: DWH, Houston, TX - Destination: DWH, Houston, TX - Airport: DWH, David Wayne Hooks Airport ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 57; injuries: none; commercial; medical: class 2, with waivers/limitations; last flight review May 23, 2013; seat: right; restraint: 4-point; flight hours: 4,600 total, 93 in this make and model, 70 in the last 90 days, 20 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 160° at 6 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 84 °F, dew point 75 °F - Altimeter: 30.05 inHg - Observed at: DWH ## 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 20140730012879A](https://openairdocs.org/incident/20140730012879A), Jul 30, 2014: Bell 206B, Spring, TX, Substantial damage. The helicopter was leased from a part 135 operator to the sheriffs department for air support operations. Sheriffs department personnel were operating the… ## Docket (4 files) The files NTSB released with the investigation on October 3, 2014, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=89977. 4.2 MB in all. - NTSB 6120-1 Pilot Report (item 1, .PDF, 3.8 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40417331&FileExtension=.PDF&FileName=NTSB%206120-1%20Pilot%20Report-Redacted.PDF - Photo 1 – View of tailboom damage (item 2, .PDF, 168 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40417332&FileExtension=.PDF&FileName=Photo%201%20%E2%80%93%20View%20of%20tailboom%20damage-Master.PDF - Photo 2 – View of tail rotor blade damage (item 3, .PDF, 149 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40417333&FileExtension=.PDF&FileName=Photo%202%20%E2%80%93%20View%20of%20tail%20rotor%20blade%20damage-Master.PDF - Photo 3 – View of the main rotor tip cap damage (item 4, .PDF, 142 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40417334&FileExtension=.PDF&FileName=Photo%203%20%E2%80%93%20View%20of%20the%20main%20rotor%20tip%20cap%20damage-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.