# NTSB DFW07CA037: Hughes 269B, N9396F, Houma, LA, December 11, 2006 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: December 11, 2006, 15:45 local (21:45 UTC) - Place: Houma, LA - Coordinates: 29.5597222222222, -90.6561111111111 - Nearby events: https://openairdocs.org/map.md?lat=29.5597&lon=-90.6561&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report March 26, 2007 - Report: Approved by Office Director - Parties: Baton Rouge, Louisiana - NTSB case key (mKey): 65005 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DFW07CA037 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/65005/pdf - Page: https://openairdocs.org/ntsb/DFW07CA037 ## Probable cause A partial loss of engine power as a result of a cracked engine cylinder and broken spark plug which resulted in a hard landing. A factor was that it was not possible to attain proper rotor RPM. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(partial) - mech failure/malf, landing - engine assembly,cylinder - cracked (cause) - ignition system,spark plug - fractured (cause) - Hard landing, landing - flare/touchdown - autorotation - initiated, pilot in command(cfi) - rotor rpm - not possible, pilot in command(cfi) (contributing factor) ## Analysis The 2,873-hour flight instructor, who reported having accumulated 550-hours in the same make and model helicopter, reported that during a training flight, while practicing touchdown autorotations, the helicopter shuttered with a slight vibration through the airframe on climb out. The flight instructor added that the vibration stopped and he elected to continue the climb turning toward a downwind leg for the next autorotation. The helicopter shuttered again, this time much more violently, while on the downwind leg. The pilot stated on the NTSB Form 6120.1, Pilot/Operator Accident/Incident Report, that "I felt like the gearbox was locking up or something." The rated student pilot who was flying the helicopter at the time then declared "you've got the controls" to the instructor. The flight instructor immediately entered autorotation and the shutter stopped. In an attempt to regain powered flight the instructor then reapplied throttle which immediately created a violent vibration again and he decided to roll throttle completely off and continue with the emergency landing. The altitude at the onset was approximately 400 feet above ground level (agl). The flight instructor initiated a 180-degree turn autorotation to align the helicopter into the prevailing wind. The flight instructor also stated that the transfer of controls and attempt to regain powered flight, followed by the delay in entering the autorational turn, created a low airspeed and low rotor RPM situation that made the successful landing not possible. The flight instructor stated that he "waited until the last second and pulled the collective up to the stops and prayed." The helicopter landed hard and managed to remain in the upright position. The flight instructor and the rated student pilot were not injured. An FAA inspector, who traveled to the site, noted that the spark plug and helicoil was broken out on the number two cylinder. Further inspection of the number two cylinder revealed three separate cracks in the cylinder wall. At the time of the accident, the winds were reported from 070 degrees at 10 knots, gusting to 15 knots. ## Factual narrative The 2,873-hour flight instructor, who reported having accumulated 550-hours in the same make and model helicopter, reported that during a training flight, while practicing touchdown autorotations, the helicopter shuttered with a slight vibration through the airframe on climb out. The flight instructor added that the vibration stopped and he elected to continue the climb turning toward a downwind leg for the next autorotation. The helicopter shuttered again, this time much more violently, while on the downwind leg. The pilot stated on the NTSB Form 6120.1, Pilot/Operator Accident/Incident Report, that "I felt like the gearbox was locking up or something." The rated student pilot who was flying the helicopter at the time then declared "you've got the controls" to the instructor. The flight instructor immediately entered autorotation and the shutter stopped. In an attempt to regain powered flight the instructor then reapplied throttle which immediately created a violent vibration again and he decided to roll throttle completely off and continue with the emergency landing. The altitude at the onset was approximately 400 feet above ground level (agl). The flight instructor initiated a 180-degree turn autorotation to align the helicopter into the prevailing wind. The flight instructor also stated that the transfer of controls and attempt to regain powered flight, followed by the delay in entering the autorational turn, created a low airspeed and low rotor RPM situation that made the successful landing not possible. The flight instructor stated that he "waited until the last second and pulled the collective up to the stops and prayed." The helicopter landed hard and managed to remain in the upright position. The flight instructor and the rated student pilot were not injured. An FAA inspector, who traveled to the site, noted that the spark plug and helicoil was broken out on the number two cylinder. Further inspection of the number two cylinder revealed three separate cracks in the cylinder wall. ## Aircraft - Registration: [N9396F](https://openairdocs.org/deregistered/N9396F-2008-07-14), registration cancelled 2008-07-14, S/N 84-0126, built 1964 (OpenAirDocs) - Reported make and model: Hughes 269B - Registry model: [Hughes 269B](https://openairdocs.org/model/hughes-269b) (registry code 4470502) (OpenAirDocs) - Registry engine: [Lycoming HIO-360 series](https://openairdocs.org/engine/lycoming-hio-360-series) (registry code 41524, reciprocating) (OpenAirDocs) - Category: Helicopter - Serial number: 840126 - Airframe hours: 13337 - Engines: Lycoming HIO360A1D 180 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Registered owner: Johnston Flying Service, Inc. - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, December 1, 2006 - Departed: KHUM, Houma, LA - Destination: KHUM - Airport: KHUM, Houma-Terrebonne Airport ## Flight crew As NTSB recorded them. NTSB leaves out names. - Flight instructor; age 45; injuries: none; airline transport, commercial, flight instructor; airplane ratings: multi-engine land, single-engine land; instrument ratings: helicopter, airplane; medical: class 2, with waivers/limitations; last flight review September 1, 2006; seat: left; flight hours: 2,873 total, 550 in this make and model, 2,664 as pilot in command, 210 in the last 90 days, 56 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 90° at 12 knots - Visibility: 7 statute miles - Lowest ceiling: 3,500 ft broken - Temperature: 73 °F, dew point 63 °F - Altimeter: 30.22 inHg - Observed at: KHUM ## 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 20061211028799A](https://openairdocs.org/incident/20061211028799A), Dec 11, 2006: Hughes 269B, Houma, LA, Destroyed. (-23) N9396F was on local training flight for helicopter CFI rating. Student pilot at the controls on climbout when aircraft experienced a shudder at… 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.