# NTSB DFW08IA045: Bell 407, N407AK, Hig Island A595, December 15, 2007 - Type: NTSB incident investigation - Classification: Incident · No injuries · Incident investigation · Final report - Date: December 15, 2007, 14:58 local (20:58 UTC) - Place: Hig Island A595 - Coordinates: 27.930555, -93.763885 - Nearby events: https://openairdocs.org/map.md?lat=27.9306&lon=-93.7639&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report March 31, 2008 - Report: Approved by Office Director - Parties: Baton Rouge, Lousiana - NTSB case key (mKey): 67261 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DFW08IA045 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/67261/pdf - Page: https://openairdocs.org/ntsb/DFW08IA045 ## Probable cause The loss of tail rotor effectiveness for undetermined reasons. ## Analysis During cruise flight, the commercial pilot experienced a violent vibration in the airframe followed by a loud "pop" and the helicopter began to yaw to the right. The pilot attempted to correct the adverse yaw but could not regain tail rotor control. The pilot deployed the floatation system and performed an autorotation onto the water. Both pilot and passenger were able to egress the helicopter without incident and entered a life raft. While awaiting rescue the pilot visually inspected the helicopter and could observe no damage or malfunction. A US Coast Guard helicopter crew rescued the pilot and passenger from the water. Prior to recovery, the helicopter capsized due to the rough seas, sank and was not recovered. ## Factual narrative On December 15, 2007, approximately 1458 central standard time, a single-engine Bell 407 helicopter, N407AK, registered to and operated by Rotorcraft Leasing Company LLC, lost tail rotor control while in cruise flight over the Gulf of Mexico approximately 98-nautical miles off the coast of Texas. The commercial pilot successfully autorotated the helicopter to the ocean. The pilot and his passenger were able to enter a life raft and were not injured. A visual flight rules flight plan was filed and visual meteorological conditions prevailed for the 14 Code of Federal Regulations Part 135 on-demand air taxi flight. The flight originated at 1453 from offshore platform High Island A573A, and was bound for offshore platform High Island A376, in the Gulf of Mexico. On a NTSB Form 6120, the 2,075-hour pilot stated that during cruise flight, he experienced a violent vibration in the airframe. Within a few seconds a noise similar to a loud "pop" was heard and the helicopter began to yaw to the right. The pilot attempted to correct the adverse yaw but could not regain control of the helicopter. Rather than continue flight or attempt a platform landing with a loss of tail rotor effectiveness, the pilot elected to perform an autorotation in the Gulf of Mexico. A distress message was transmitted and the emergency floatation system was activated prior to landing. Once successfully landed, the pilot radioed a position report and shutdown the helicopter. The life raft was deployed and both pilot and passenger successfully egressed the helicopter. While waiting for the US Coast Guard, the pilot visually inspected the helicopter and could observe no damage or malfunction. A Coast Guard helicopter crew recovered both personnel. The helicopter was capsized due to swells in excess of 15 feet, sank and was not recovered. At 1452 weather reported at Scholes International Airport, Galveston, Texas, approximately 105 nm northeast was winds from 320 degrees at 21 knots gusting to 27 knots, temperature 63 degrees Fahrenheit, and a barometric pressure of 29.98 inches of Mercury. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Airframe/component/system failure/malfunction, cruise - rotorcraft flight control,tail rotor control - malfunction (cause) - loss of tail rotor effectiveness - encountered, pilot in command - Forced landing, descent - emergency - terrain condition - water - emergency floats - activated, pilot in command - On ground/water encounter with weather, landing - weather condition - other ## Aircraft - Registration: [N407AK](https://openairdocs.org/deregistered/N407AK-2009-03-17), registration cancelled 2009-03-17, S/N 53269, built 1998 (OpenAirDocs) - Reported make and model: Bell 407 - Registry model: [Bell 407](https://openairdocs.org/model/bell-407) (registry code 1182206) (OpenAirDocs) - Registry engine: [Allison 250-C47 series](https://openairdocs.org/engine/allison-250-c47-series) (registry code 03029, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: 53269 - Airframe hours: 3972 - Engines: Rolls-Royce 250-C47B 650 horsepower turbo shaft - Damage: No damage - Flight: Part 135 - Registered owner: Rotorcraft Leasing Compnay, LLC - Airworthiness certificate: Standard, Normal - Last inspection: AAIP, December 1, 2007 - Departed: A573, HI A573A, GM - Destination: A376, HI A376, GM - Flight plan: VFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 28; injuries: none; flight instructor, commercial; instrument ratings: helicopter; medical: class 2, with waivers/limitations; last flight review October 1, 2007; seat: right; flight hours: 2,075 total, 84 in this make and model, 1,991 as pilot in command, 179 in the last 90 days, 54 in the last 30 days, 6 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 320° at 21 knots, gusting 27 - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 63 °F, dew point 43 °F - Altimeter: 29.97 inHg - Observed at: KGLS, 105 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). - [Incident 20071215829179I](https://openairdocs.org/incident/20071215829179I), Dec 15, 2007: Bell 407, Gulf Of Mexico, US, No damage. (-23) Helicopter was operating offshore (galveston VOR 135/100) enroute from one oil platform to another when the aircraft experienced significant vibrations,… From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date; 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.