# NTSB ERA09LA047: Bell 206B, N281CB, Boynton Beach, FL, November 11, 2008 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: November 11, 2008, 06:10 local (11:10 UTC) - Place: Boynton Beach, FL - Coordinates: 26.548889, -80.072502 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=26.5489&lon=-80.0725&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute: Powerplant sys/comp malf/fail](https://openairdocs.org/ntsb-events/340) - Highest injury: Minor injuries - Injuries: 2 minor - Status: Completed, report June 11, 2009 - Report: Approved by Office Director - NTSB office: Eastern Region Aviation - Parties: FAA/FSDO, Rolls-Royce Corporation - NTSB case key (mKey): 69425 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA09LA047 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/69425/pdf - Page: https://openairdocs.org/ntsb/ERA09LA047 ## Probable cause A loss of engine power due to an undertorqued air line fitting to the fuel control. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Engine fuel and control: fuel distribution](https://openairdocs.org/ntsb-findings/01057310): Aircraft › Aircraft power plant · Incorrect service/maintenance (probable cause); cases with it: [Bell 206B, 1 case](https://openairdocs.org/ntsb-findings/01057310/cases.md?model=1181511), [All aircraft, 55 cases](https://openairdocs.org/ntsb-findings/01057310/cases.md) - [Maintenance](https://openairdocs.org/ntsb-findings/02062000): Personnel issues › Task performance · Not specified (probable cause); cases with it: [Bell 206B, 2 cases](https://openairdocs.org/ntsb-findings/02062000/cases.md?model=1181511), [All aircraft, 143 cases](https://openairdocs.org/ntsb-findings/02062000/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: [Bell 206B, 4 cases](https://openairdocs.org/ntsb-events/040/sequence.md?model=1181511), [All aircraft, 484 cases](https://openairdocs.org/ntsb-events/040/sequence.md) - [Enroute: Powerplant sys/comp malf/fail](https://openairdocs.org/ntsb-events/340) (defining event); cases with it: [Bell 206B, 3 cases](https://openairdocs.org/ntsb-events/340/sequence.md?model=1181511), [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: [Bell 206B, 21 cases](https://openairdocs.org/ntsb-events/440/sequence.md?model=1181511), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) - [Landing: Hard landing](https://openairdocs.org/ntsb-events/092); cases with it: [Bell 206B, 28 cases](https://openairdocs.org/ntsb-events/092/sequence.md?model=1181511), [All aircraft, 2,102 cases](https://openairdocs.org/ntsb-events/092/sequence.md) ## Analysis Approximately 8 minutes after the helicopter departed, the engine lost power and the pilot initiated an autorotation. To clear powerlines near the forced landing area, the pilot used collective to extend the helicopter's glide. The helicopter then touched down hard, severing the tail boom. Examination of the engine revealed that the "B"-nut for the pressure compressor (Pc) line from the power turbine governor to the fuel control unit was detached. Prior to an engine test run at the manufacturer's facility, the "B"-nut was placed in the same manner in which it was found at the accident site, with no thread engagement. The engine was started, warmed up, and throttle advanced to 65 percent N1. The engine experienced an uncommanded power reduction and decelerated to a sub-idle setting. A visual examination showed that the "B"-nut had loosened entirely and there was a gap between the Pc line and the "T"-fitting. After the Pc line was reinstalled and the "B"-nut was tightened with the proper torque, the engine was restarted and ran within production test standards. The Rolls-Royce operation and maintenance manual gave a warning that "failure to properly install, align and tighten fuel, oil, and air fittings and tubes could result in an engine failure." On November 8, 2008, an entry in the engine logbook indicated that the engine gearbox had been opened and inspected this process required the "B"-nut to be loosened and the lines separated to access the gearbox. ## Factual narrative HISTORY OF FLIGHT On November 11, 2008, about 0610 eastern standard time, a Bell 206B, N281CB, owned and operated by Aircoastal Helicopters, Inc., was substantially damaged when it impacted the ground during a forced landing. The helicopter departed Palm Beach County Park Airport (LNA), Lantana, Florida, about 0602. The certificated airline transport pilot and passenger received minor injuries. The flight was operated under the provisions of 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed at the time and no flight plan was filed for the local traffic report flight which was conducted for a local television station. According to the operator, the accident flight departed from LNA, climbed to approximately 1,000 feet above ground level (agl), flew to the south, and after a few minutes the helicopter was turned to fly northbound. Shortly after the completion of the turn, the helicopter yawed to the left and the low rotor and engine out warning systems activated. The pilot entered an autorotation, and achieved a normal rotor rpm. He then selected a landing site on a road within an industrial park; however, as the helicopter approached the intended landing area, the pilot noticed powerlines spanning across the road. The pilot was able to utilize the collective control to clear the powerlines, and impacted in a grass area along the road. PERSONNEL INFORMATION According to Federal Aviation Administration (FAA) records, the pilot, age 51, held an airline transport pilot certificate and a certificated flight instructor certificate each with a rating for helicopter. His most recent FAA second-class medical certificate was issued on November 13, 2007. According to the pilot he had accumulated 2,708 total hours of flight experience and 137 total hours of flight experience in make and model of helicopter. His last biennial flight review was completed on January 24, 2008. AIRCRAFT INFORMATION According to FAA records, the helicopter was manufactured in 1981 and issued an airworthiness certificate on April 16, 1981. The helicopter was equipped with an Allison 250-C20B series, gas-turbine engine. Airframe logbook entries dated October 9, 2008, indicated that the airframe had been inspected in accordance with the manufacturer's 100/200 hour inspections. Engine logbook entries dated November 8, 2008, indicated that the engine gearbox had been opened and inspected, with no defects found. The owner of the helicopter stated that the airframe had a total time in service of 12,540.70 hours and 12,391 total cycles. The engine had a total time in service of 14,420.70 hours. METEOROLOGICAL INFORMATION The 0619 recorded weather observation at Palm Beach International Airport (PBI), West Palm Beach, Florida, 10 miles north of the accident site; included winds from 060 degrees at 10 knots, few clouds at 2,600 feet agl, broken cloud layers at 4,100 feet agl, and an overcast cloud layer at 4,700 feet agl, 10 miles visibility, temperature 24degrees Celsius (C), dew point 18 degrees C, and an altimeter setting of 30.02 inches of mercury. WRECKAGE AND IMPACT INFORMATION The helicopter was examined by an FAA inspector who responded to the accident site. The helicopter's tail boom was severed aft of the horizontal stabilizer, the landing skids and rear cross tube were damaged, the hull was damaged, the fuel cell was ruptured, and the smell of fuel was reported at the accident site. Engine continuity was verified through the driveshaft and continuity was confirmed through the engine to the compressor and was rotated through the starter generator. Tail rotor continuity was verified from the tail rotor forward to the separation, and flight control continuity was verified. Further examination revealed a loose pressure compressor (Pc) line from the power turbine governor to the fuel control unit and the "B"-nut was found loose to the point of no thread engagement. The wreckage was recovered by the owner and transported to the owner's hangar at LNA, under the supervision of an FAA inspector. The engine was subsequently removed from the helicopter, and sent to the engine manufacturer's facility for further evaluation. TEST AND RESEARCH The engine was examined at Rolls-Royce, Indianapolis, Indiana, on January 13, 2009, under the supervision of an FAA inspector. According to the FAA inspector, the engine was removed from the shipping container, and exhibited minimal damage. According to the Rolls-Royce engine investigation report, the "B"-nut was placed in the same manner in which it was found, with no thread engagement, the engine was started, warmed up, throttle was advanced to 65 percent N1, and remained at that cruise setting. Subsequently the engine experienced an uncommanded power reduction and decelerated to a sub-idle setting. A visual examination showed the "B"-nut had loosened and there was a gap between the Pc line and the "T"-fitting. The Pc line was reinstalled and "B"-nut tightened with the proper torque, restarted, and ran within production test standards. In the Rolls-Royce Operation and Maintenance manual section 73-00-00, Engine Fuel and Control System - Maintenance Practices, Fuel System Maintenance states, "Warning: Failure to properly install, align and tighten fuel, oil, and air fittings and tubes could result in an engine failure." ## Aircraft - Registration: [N281CB](https://openairdocs.org/deregistered/N281CB-2023-03-04), registration cancelled 2023-03-04, S/N 3303, 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-C20 series](https://openairdocs.org/engine/allison-250-c20-series) (registry code 03020, turbo-prop) (OpenAirDocs) - Category: Helicopter - Serial number: 3303 - Airframe hours: 12508 - Engines: Allison 250 420 horsepower turbo shaft - Damage: Substantial damage - Flight: Aerial observation, Part 91 - Operator: Air Coastal Helicoters Inc. - Registered owner: Air Coastal Helicoters Inc. - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, October 9, 2008, 133 hours before - Departed: LNA, Lantana, FL - Destination: LNA, Lantana, FL - Flight plan: Company VFR - Airport: LNA, Palm Beach County Park Airport ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 51; injuries: minor; flight instructor, airline transport; instrument ratings: helicopter; medical: class 2, without waivers/limitations; last flight review January 24, 2008; seat: right; flight hours: 2,708 total, 137 in this make and model, 2,604 as pilot in command, 200 in the last 90 days, 40 in the last 30 days ## Weather - Conditions: Visual (VMC), Dawn - Wind: 60° at 10 knots - Visibility: 10 statute miles - Lowest ceiling: 4,100 ft broken - Temperature: 75 °F, dew point 64 °F - Altimeter: 30.02 inHg - Observed at: PBI, 10 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 20081111856619A](https://openairdocs.org/incident/20081111856619A), Nov 11, 2008: Bell 206B, West Palm Beac, FL, Substantial damage. (-23) On 11/11/08, at approximately 0610, a Bell 206B helicopter N281CB piloted by [privacy data omitted], experienced total power loss. [privacy data omitted]… 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.