# NTSB DEN04CA122: Eurocopter France EC-130 B4, N910U, Englewood, CO, August 9, 2004 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: August 9, 2004, 17:00 local (23:00 UTC) - Place: Englewood, CO - Coordinates: 39.567222, -104.849998 - Nearby events: https://openairdocs.org/map.md?lat=39.5672&lon=-104.8500&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 3 uninjured - Status: Completed, report October 28, 2004 - Report: Approved by Office Director - Parties: FAA Flight Standards District Office - NTSB case key (mKey): 59880 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN04CA122 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/59880/pdf - Page: https://openairdocs.org/ntsb/DEN04CA122 ## Probable cause the pilot's failure to perform a preflight inspection. Contributing to the accident was the transmission cowling that disconnected during the landing. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Airframe/component/system failure/malfunction, hover - in ground effect - aircraft preflight - not performed, pilot in command (cause) - door,service - disconnected (contributing factor) ## Analysis According to the pilot, the helicopter had just undergone maintenance and was preparing for a second test flight. The helicopter had departed approximately 15 minutes prior to the accident and returned due to an inoperative horizontal situation indicator. A thorough preflight had been conducted for the first test flight. While the HSI was being repaired, another maintenance technician opened the transmission cowling. The pilot and two avionics technicians boarded the helicopter from the left side, without performing an additional preflight or walk around. The pilot performed a run-up and lifted the helicopter to a hover when an individual on the ground noticed that the cowling was open. The lead mechanic then signaled to the pilot for him to land. As the helicopter set back down, the transmission cowling detached and impacted a main rotor blade and the tail boom, causing substantial damage. ## Factual narrative On August 9, 2004, at approximately 1700 mountain daylight time, a Eurocopter EC 130 B4, N910U, operated by Air Methods and piloted by a commercial pilot, was substantially damaged during ground hover operations at Centennial Airport, Englewood, Colorado. Visual meteorological conditions prevailed at the time of the accident. The test flight was being conducted under the provisions of Title 14 CFR Part 91 without a flight plan. The pilot reported no injuries. The local flight was originating at the time of the accident. According to the accident report submitted by the pilot, the helicopter had just undergone maintenance and was preparing for a second test flight. The helicopter had departed approximately 15 minutes prior to the accident and returned due to an inoperative HSI. A thorough preflight had been conducted for the first test flight. While the HSI was being repaired, another maintenance technician opened the transmission cowling. The pilot and two avionics technicians boarded the helicopter from the left side, without performing an additional preflight or walk around. The pilot performed a run-up and lifted the helicopter to a hover when an individual on the ground noticed that the cowling was open. The lead mechanic then signaled to the pilot for him to land. As the helicopter set back down, the transmission cowling detached and impacted a main rotor blade and the tail boom. The main rotor blade was damaged at the root and the tail boom was creased and punctured. After the accident, the mechanic reported that it was hot inside and he decided to leave the cowling open. ## Aircraft - Registration: [N910U](https://openairdocs.org/aircraft/N910U), registered now, S/N 3470, built 2001 (OpenAirDocs) - Reported make and model: Eurocopter France EC-130 B4 - Registry model: [Eurocopter EC 130 B4](https://openairdocs.org/model/eurocopter-ec-130-b4) (registry code 8680989) (OpenAirDocs) - Registry engine: [Turbomeca ARRIEL-2B1](https://openairdocs.org/engine/turbomeca-arriel-2b1) (registry code 60056, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: 3470 - Airframe hours: 85.1 - Engines: Turbomeca Arriel 2B1 557 horsepower turbo shaft - Damage: Substantial damage - Flight: Flight test, Part 91 - Operator: Air Methods, doing business as Air Methods - Registered owner: Banc One Leasing Corp - Airworthiness certificate: Standard, Normal - Last inspection: AAIP, August 6, 2004, 0.2 hours before - Departed: APA, Englewood, CO - Destination: APA - Airport: APA, Centennial ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 48; injuries: none; commercial, flight instructor; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane, helicopter; medical: class 2, valid medical--w/ waivers/lim; last flight review June 1, 2004; seat: left; flight hours: 6,980 total, 180 in this make and model, 6,810 as pilot in command, 40 in the last 90 days, 15 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 350° at 9 knots, gusting 17 - Visibility: 10 statute miles - Lowest ceiling: 5,000 ft broken - Temperature: 79 °F, dew point 54 °F - Altimeter: 30.26 inHg - Observed at: APA ## 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 20040809024779A](https://openairdocs.org/incident/20040809024779A), Aug 9, 2004: Urocop EC130B4, Denver, CO, Minor damage. (-23) The aircraft was positioned on the ramp at the air methods maintenance facility. The aircraft was undergoing some avionics adjustments by two… 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.