# NTSB DEN04LA145: Bell 214B-1, N214B, Aspen, CO, September 17, 2004 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: September 17, 2004, 13:00 local (19:00 UTC) - Place: Aspen, CO - Coordinates: 39.189746, -106.819412 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=39.1897&lon=-106.8194&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report September 13, 2005 - Report: Approved by Office Director - Parties: FederalAviation Administration - NTSB case key (mKey): 60162 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN04LA145 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/60162/pdf - Page: https://openairdocs.org/ntsb/DEN04LA145 ## Probable cause the inadvertent activation of the engine's fuel shut off valve, resulting in the reduction of engine power to 50 percent due to an improper cannon plug wire repair on the engine's wire harness assembly. Contributing factors include the improper wire repair, the low altitude, and the lack of suitable terrain for a forced landing. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(partial) - nonmechanical, hover - out of ground effect - maintenance,modification - improper (cause) - fuel system,fuel shutoff - activated (cause) - electrical system - inadvertent activation (cause) - electrical system,electric wiring - shorted (cause) - Forced landing, descent - emergency - autorotation - attempted, pilot in command - In flight collision with terrain/water, descent - emergency - altitude - low (contributing factor) - terrain condition - high terrain - terrain condition - downhill - terrain condition - none suitable (contributing factor) ## Analysis According to the pilot, as he brought the helicopter to a 90-foot hover, he felt a "slight shudder" as the engine experienced a compressor stall. He stated that the engine rpm dropped to idle and he noticed the fuel flow had dropped to "idle fuel flow." He turned the helicopter downhill and attempted a forced landing on a nearby ski slope. The helicopter struck the ground with its nose, slid approximately 30 feet, and rolled over on its left side. The impact crushed the forward section of the fuselage, buckled the tail boom, and separated the vertical fin, tail rotor assembly, and both landing gear skids. The engine continued to run at idle after the helicopter came to rest. During a serviceability inspection of the engine's wire harness, a broken wire was located in the overspeed control unit's cannon plug. The wire in the "crimp type" cannon plug had been repaired with a solder joint, which is not allowed due to the close tolerance of the pins. According to the technician, the broken wire condition, in itself, would not engage the overspeed system or result in the loss of engine power. However, it was noted that, due to the close tolerance of the pins, any movement of the broken wire could enable the solder joint on one pin to touch the other pin. During a bench test, the technician stated that he "shorted pin B to pin C." This shorted condition resulted in the inadvertent activation of the fuel shut-off valve, which would result in the reduction of engine power to approximately 50 percent. ## Factual narrative On September 17, 2004, at approximately 1300 mountain daylight time, a Bell 214B-1, N214B, operated by Central Copters, Inc., was substantially damaged during a forced landing following a loss of engine power near Aspen, Colorado. Visual meteorological conditions prevailed at the time of the accident. The local flight was being conducted under the provisions of Title 14 CFR Part 91 without a flight plan. The commercial certificated pilot was not injured. The flight was originating at the time of the accident. According to the pilot, he was departing a staging area on the side of a ski slope. As he brought the helicopter to a hover at approximately 90 feet agl, he felt a "slight shudder" as the engine experienced a compressor stall. He stated that the engine rpm dropped to idle and he noticed the fuel flow had dropped to "idle fuel flow." He turned the helicopter downhill and attempted a forced landing on a nearby ski slope. The helicopter struck the ground with its nose, slid approximately 30 feet, and rolled over on its left side. The impact crushed the forward section of the fuselage, buckled the tail boom, and separated the vertical fin, tail rotor assembly, and both landing gear skids. The engine continued to run at idle after the helicopter came to rest. On November 3, 2004, the engine was examined and functionally tested. No pre-impact conditions were found that would have interfered with normal engine operation. The engine performed normally throughout the functional test and the test could not duplicate the loss of power condition as described by the pilot. On April 26, 2005, a maintenance technician completed a serviceability inspection of the engine's wire harness assembly. The wire harness assembly, which connects the airframe to various engine components, was in "very poor condition with bare wires showing, plugs in deteriorated condition [and] with o-rings missing." The harness was not in a "serviceable condition." During the inspection, he identified a broken cannon plug wire. The broken wire was identified as the lead wire for pin B in the engine's overspeed trip system cannon plug. Upon further inspection, he noted that, on the same cannon plug, the lead wire for pin A broke free with very little effort. The two cannon plug wires were identified as the primary power and ground wires for the engine's overspeed control unit. An examination of the cannon plug revealed that the wire had been repaired with a solder joint. The original insulation between the sockets had been removed and the solder joints were covered with heat shrink tubing. The cannon plug (1P32, p/n PT06CP-8-4S) is a "crimp type" cannon plug, which requires crimp pins. Soldering is not allowed due to the close tolerance of the pins. A bench test was conducted on the wire harness, in which power was applied and then removed. The technician stated that "no false triggers of the fuel [shut-off] valve" were noted. According to the technician, the broken wire condition, in itself, would not engage the overspeed system or result in the loss of engine power. However, it was noted that the broken cannon plug wire was next to the lead wire for pin C, which is connected directly to the engine's overspeed fuel shut-off valve. Movement of the broken wire could enable the solder joint on pin B to touch pin C, which could inadvertently activate the fuel shut-off valve. During a second bench test, the technician stated that he "shorted pin B to pin C." This shorted condition resulted in the inadvertent activation of the fuel shut-off valve, which resulted in the reduction of engine power to approximately 50 percent. No further system or airframe anomalies were noted. ## Aircraft - Registration: [N214B](https://openairdocs.org/aircraft/N214B), registered now, S/N 28039, built 1978 (OpenAirDocs) - Reported make and model: Bell 214B-1 - Registry model: [Bell 214B-1](https://openairdocs.org/model/bell-214b-1) (registry code 1182105) (OpenAirDocs) - Registry engine: [Lycoming T-55 SER TS](https://openairdocs.org/engine/lycoming-t-55-ser-ts) (registry code 41555, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: 28039 - Airframe hours: 7810 - Engines: Allied Signal T-55 O8D 2950 horsepower turbo shaft - Damage: Substantial damage - Flight: Other work use, Part 91 - Registered owner: Central Copters Inc. - Airworthiness certificate: Standard, Transport - Departed: ASE, Aspen, CO - Destination: ASE, Aspen, CO - Airport: ASE, Aspen-Pitkin Co/Sardy Field ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 50; injuries: none; commercial; airplane ratings: single-engine land, single-engine sea; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; last flight review April 1, 2004; seat: right; flight hours: 21,800 total, 675 in this make and model, 100 in the last 90 days, 50 in the last 30 days, 3 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 270° at 10 knots, gusting 19 - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 77 °F, dew point 18 °F - Altimeter: 30.20 inHg - Observed at: KASE, 5 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 20040917022969A](https://openairdocs.org/incident/20040917022969A), Sep 17, 2004: Bell 214B1, Aspen, CO, Destroyed. (-23) Shortly after takeoff the aircraft came to a hover at approx. 80' AGL and had just started forward flight when the aircraft lost power. Pilot entered… 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.