# NTSB ATL02LA044: Hiller UH12E, N103HA, Miami, FL, February 11, 2002 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: February 11, 2002, 17:06 local (22:06 UTC) - Place: Miami, FL - Coordinates: 25.793056, -80.290275 - Nearby events: https://openairdocs.org/map.md?lat=25.7931&lon=-80.2903&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report November 25, 2003 - Report: Approved by Office Director - Parties: FAA Miami FSDO - NTSB case key (mKey): 54197 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ATL02LA044 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/54197/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=54197 - Page: https://openairdocs.org/ntsb/ATL02LA044 ## Probable cause Fatigue cracking in the main rotor hub that resulted in the separation of the main rotor system. A factor was corrosive deposits on the exposed portion of the plate set pin. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Rotor failure/malfunction, maneuvering - aerial application - rotor system,main rotor hub - fractured (cause) - rotor system,main rotor hub - corroded (contributing factor) - rotor system,main rotor hub - fatigue (cause) - Forced landing, emergency descent/landing - In flight collision with terrain/water, emergency landing - terrain condition - ground ## Analysis A Hiller UH-12E collided with the ground during a forced landing. According to the pilot, while executing aerial applications at 15 to 20 feet AGL, he heard a bang and the helicopter began shaking and yawing. The pilot realized he was losing altitude and attempted to slow the descent by using the collective. The helicopter impacted the ground, and caught fire. The pilot exited the helicopter through a hole in the bubble. Examination of the main rotor hub pieces revealed that the fracture at the hub had progressed through the inboard pin hole for the torsion/tension plate set. Six fracture faces were noted in the examination corresponding with the pin hole. Two fracture faces showed discoloration with a distinctive banding pattern and smoothly curved crack arrest marks consistent with fatigue propagation. Examination of the remaining two fractures revealed no evidence of fatigue cracking, but did show some corrosion on the exposed portion of the pin. ## Factual narrative On February 11, 2002, at 1706 eastern standard time, a Hiller UH12E, N103HA, registered to and operated by a private owner, under the provisions of Title 14 CFR part 137, collided with the ground during a forced landing in Miami, Florida. The aerial application flight operated under visual flight rules with no flight plan filed. Visual weather conditions prevailed at the time of the accident. The helicopter was substantially damaged, and the pilot was not injured. The flight initially departed Miami, Florida, on February 11, 2002 at 1700. According to the commercial pilot, while executing aerial applications at 15 to 20 feet AGL, he heard a bang and the helicopter began shaking and yawing. The pilot realized he was losing altitude and attempted to slow the descent by using the collective. The helicopter impacted the ground, and caught fire. The pilot exited the helicopter through a hole in the plexiglass bubble. Examination of the helicopter showed that the transmission, main rotor, and control rods were broken from the helicopter. The main rotor blades were found lying approximately 150 feet from the accident site, and were bent. The instrument panel, skids, tail rotor drive, main rotor hub, intake, and bubble were all broken, with the main rotor hub broken into two pieces. The National Transportation Safety Board, Office of Research and Engineering, Materials Laboratory Division, performed metallurgical examination of the main rotor hub pieces. Examination of the main rotor hub pieces revealed that the fracture at the hub had progressed through the inboard pin hole for the torsion/tension plate set. Six fracture faces were noted in the examination corresponding with the pin hole. Two fracture faces showed discoloration with a distinctive banding pattern and smoothly curved crack arrest marks consistent with fatigue propagation. The mating faces of the two discolored fracture faces were found to match the aforementioned fractures. Examination of the remaining two fractures revealed no evidence of fatigue cracking, but did show some corrosion on the exposed portion of the pin. Main rotor hub history and time in service were not available for review, however, the last reported annual inspection was completed on February 2, 2002, about 22 hours before the accident. ## Aircraft - Registration: [N103HA](https://openairdocs.org/deregistered/N103HA-2003-09-09), registration cancelled 2003-09-09, S/N HA3003, built 1973 (OpenAirDocs) - Reported make and model: Hiller UH12E - Registry model: [Hiller UH-12E](https://openairdocs.org/model/hiller-uh-12e) (registry code 4360122) (OpenAirDocs) - Registry engine: [Lycoming VO-540 series](https://openairdocs.org/engine/lycoming-vo-540-series) (registry code 41534, reciprocating) (OpenAirDocs) - Category: Helicopter - Serial number: HA3003 - Airframe hours: 5481 - Engines: Lycoming VO540C2A 305 horsepower reciprocating - Damage: Substantial damage - Fire: On-Ground - Flight: Aerial application, Part 137 - Registered owner: Marvin Scripter - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, February 2, 2002, 23 hours before - Departed: Miami, FL - Airport: NONE, private ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 39; injuries: minor; flight instructor, commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; last flight review January 8, 2001; seat: center; flight hours: 2,239 total, 650 in this make and model, 2,130 as pilot in command, 70 in the last 90 days, 39 in the last 30 days, 4 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 200° at 7 knots - Visibility: 10 statute miles - Lowest ceiling: 90 ft broken - Temperature: 73 °F, dew point 61 °F - Altimeter: 30.10 inHg - Observed at: TMB, 3 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). - [Accident 20020211001129A](https://openairdocs.org/incident/20020211001129A), Feb 11, 2002: Hiller UH12E, Miami, FL, No damage. (.19) On February 11, 2002, at 1706 central standard time, a Hiller UH-12E, N103HA, operated by slimline aviation inc., under the provisions of title 14 CFR… ## Docket (3 files) The files NTSB released with the investigation on October 9, 2003, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=54197. 2.3 MB in all. - Materials Laboratory 15 - Factual Report 02-101 (item 1, .PDF, 1.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40173965&FileExtension=.PDF&FileName=Materials%20Laboratory%2015%20-%20Factual%20Report%2002-101-Master.PDF - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 2, .PDF, 620 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40387336&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - UH12E Parts Catalog (item 3, .PDF, 149 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40187651&FileExtension=.PDF&FileName=UH12E%20Parts%20Catalog-Master.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.