# NTSB FTW01LA202: Hiller UH-12D, N2770, Lubbock, TX, September 3, 2001 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: September 3, 2001, 16:10 local (21:10 UTC) - Place: Lubbock, TX - Coordinates: 33.640712, -101.77919 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=33.6407&lon=-101.7792&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report May 21, 2002 - Report: Approved by Office Director - Parties: FAA FSDO - NTSB case key (mKey): 53166 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW01LA202 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/53166/pdf - Page: https://openairdocs.org/ntsb/FTW01LA202 ## Probable cause the failure of the tail rotor drive shaft hanger bearing, which resulted in the separation of the tail rotor drive shaft. A contributing factor was the lack of suitable terrain for the forced landing. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Airframe/component/system failure/malfunction, maneuvering - aerial application - rotor drive system,tail rotor drive shaft bearing - failure (cause) - rotor drive system,tail rotor drive shaft - separation (cause) - Forced landing, descent - emergency - Hard landing, landing - flare/touchdown - terrain condition - none suitable (contributing factor) - directional control - not possible, pilot in command - misc rotorcraft,main rotor/tail boom contact - misc rotorcraft,tail boom - separation ## Analysis The helicopter pilot was spraying a cotton field at 4 feet agl, when he felt a vibration followed by a "pop" with a loss of tail rotor control. Subsequently, during the forced landing to the cotton field, the main rotor blades struck the tailboom separating it from the fuselage. Examination of the helicopter, by an FAA inspector revealed that a tail rotor drive shaft hanger bearing had failed, and the tail rotor drive shaft had separated. ## Factual narrative On September 3, 2001, at 1610 central daylight time, a Hiller UH-12D agricultural helicopter, N2770, was substantially damaged during a forced landing following a loss of directional control near Lubbock, Texas. The helicopter was registered to the pilot and operated by Aero Management, Inc., of Olton, Texas. The commercial pilot, sole occupant, was not injured. Visual meteorological conditions prevailed, and a flight plan was not filed for the 14 Code of Federal Regulations Part 137 aerial application flight. The local flight originated from the Town and Country Airpark Airport, Lubbock, Texas, at 1515. The pilot reported to the FAA inspector that while spraying a cotton field, at 4 feet agl, he felt a vibration followed by a "pop" with a loss of tail rotor control. Subsequently, during the forced landing to the cotton field, the main rotor blades struck the tailboom separating it from the fuselage. Examination of the helicopter by the FAA inspector, who responded to the accident site, revealed that a tail rotor drive shaft hanger bearing had failed, and the tail rotor drive shaft had separated. ## Aircraft - Registration: [N2770](https://openairdocs.org/aircraft/N2770), registered now, S/N 1250 (OpenAirDocs) - Reported make and model: Hiller UH-12D - Registry model: [Hiller UH-12D](https://openairdocs.org/model/hiller-uh-12d) (registry code 4360118) (OpenAirDocs) - Registry engine: [Lycoming VO-435 series](https://openairdocs.org/engine/lycoming-vo-435-series) (registry code 41525, reciprocating) (OpenAirDocs) - Category: Helicopter - Serial number: 1250 - Airframe hours: 7946 - Engines: Lycoming VO-435-A1C 250 horsepower reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: Aero Management, Inc. - Registered owner: Micky Price - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, August 1, 2001, 79 hours before - Departed: F82, Lubbock, TX ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 44; injuries: none; commercial, flight instructor; airplane ratings: single-engine land, multi-engine land; instrument ratings: helicopter, airplane; medical: class 2, valid medical--no waivers/lim.; last flight review October 4, 1999; seat: center; flight hours: 15,400 total, 400 in this make and model, 15,204 as pilot in command, 235 in the last 90 days, 105 in the last 30 days, 5 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 235° at 5 knots - Lowest ceiling: none ## 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 20010903024659A](https://openairdocs.org/incident/20010903024659A), Sep 3, 2001: Hiller UH12D, Lubbock, TX, Substantial damage. (-23) While spraying at 4 feet AGL, a vibration started then there was a pop with the loss of tail rotor thrust, as stated by the pilot. The pilot put the… 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.