# NTSB DFW07IA212: Schweizer 269D, N8374F, Houston, TX, September 30, 2007 - Type: NTSB incident investigation - Classification: Incident · No injuries · Incident investigation · Final report - Date: September 30, 2007, 17:05 local (22:05 UTC) - Place: Houston, TX - Coordinates: 29.645277, -95.278892 - Nearby events: https://openairdocs.org/map.md?lat=29.6453&lon=-95.2789&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report July 30, 2008 - Report: Approved by Office Director - Parties: Federal Aviation Administration - NTSB case key (mKey): 66904 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DFW07IA212 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/66904/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=66904 - Page: https://openairdocs.org/ntsb/DFW07IA212 ## Probable cause The fatigue failure during hover of the drive adapter between the engine and lower pulley drive shaft. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Forced landing, hover - turboshaft engine,power output shaft - failure (cause) ## Analysis After a hover taxi and while approximately 5 feet above ground level, the pilot stopped the helicopter's forward movement, and was turning into the wind when he felt a "hard thump." The helicopter descended, impacted the ground, and yawed 20-30 degrees to the left before coming to rest in an upright position. The helicopter sustained minor damage. An examination of the helicopter by maintenance personnel revealed that the forward drive adapter of the engine to lower pulley drive shaft had fractured and separated from the aft coupling. This fracture separated the engine from the power train, resulting in loss of power to the main rotors. An examination of the drive adapter revealed that it had failed due to fatigue. ## Factual narrative On September 30, 2007, about 1705 central daylight time, a single-engine Schweizer 269D helicopter, N8374F, sustained minor damage during a forced landing at the William P Hobby Airport (HOU), near Houston, Texas. The commercial pilot and observer were not injured. The helicopter was registered to and operated by the Houston Police Department. Visual meteorological conditions prevailed and no flight plan was filed for the 14 Code of Federal Regulations Part 91 flight. The local flight was originating at the time of the accident. The pilot reported that after a hover taxied and while approximately five feet above ground level, he stopped the helicopter's forward movement and was turning into the wind when he observed a "hard thump." The helicopter descended, impacted the ground, and yawed 20-30 degrees to the left before coming to rest in an upright position. An examination of the helicopter by maintenance personnel revealed that the forward drive adapter of the engine to lower pulley drive shaft, KaFlex assembly part number SKCP2738-7 fractured and separated from the aft coupling. This fracture separated the engine from the power train resulting in loss of power to the main rotors. An examination of the drive adapter was performed at Schweizer Aircraft Corporation with oversight provided by the Federal Aviation Administration. The examination revealed that the drive adapter had failed due to fatigue. ## Aircraft - Registration: N8374F (not matched to a registry record) - Reported make and model: Schweizer 269D - Category: Helicopter - Serial number: 0032A - Airframe hours: 4712 - Engines: Rolls-Royce 250-C20W 252 horsepower turbo shaft - Damage: Minor damage - Flight: Public aircraft, Part 91 - Registered owner: Houston Police Department - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, September 1, 2007 - Departed: HOU, HOUSTON, TX - Airport: HOU, William P Hobby ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 43; injuries: none; commercial; medical: class 2, without waivers/limitations; last flight review November 1, 2006; seat: left; flight hours: 258 total, 30 in this make and model, 203 as pilot in command ## Weather - Conditions: Visual (VMC), Dawn - Wind: 130° at 3 knots - Visibility: 10 statute miles - Temperature: 81 °F, dew point 73 °F - Altimeter: 30.11 inHg ## 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 20070930022069I](https://openairdocs.org/incident/20070930022069I), Sep 30, 2007: Scwzer 269D, Houston, TX, Minor damage. (-23) Pilot taxied away from the p.d. area. Prior to take off he was turning the helicopter into the wind at which time he felt a "thump" and the helicopter… ## Docket (2 files) The files NTSB released with the investigation on June 30, 2008, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=66904. 3.6 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 3.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40296644&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Drive Adapter email (item 2, .PDF, 18 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40389880&FileExtension=.PDF&FileName=Drive%20Adapter%20email-Redacted.PDF 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.