# NTSB MIA99LA107: Fairchild Hiller FH-1100, N547FH, Opp, AL, March 16, 1999 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: March 16, 1999, 10:01 local (16:01 UTC) - Place: Opp, AL - Coordinates: 31.289867, -86.25093 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=31.2899&lon=-86.2509&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report June 23, 2000 - Report: Approved by Office Director - NTSB case key (mKey): 45941 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=MIA99LA107 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/45941/pdf - Page: https://openairdocs.org/ntsb/MIA99LA107 ## Probable cause a loss of engine power due to the failure of the engine to transmission drive shaft flex coupling, resulting in an in-flight collision with a vehicle. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power, hover - in ground effect - rotor drive system,engine to transmission drive - failure,total (cause) - rotor drive system,engine to transmission drive - corroded - In flight collision with object, hover - in ground effect - object - vehicle ## Analysis The helicopter had completed a 2-hour aerial application flight and returned to the helipad to refuel and reload. The helipad was a flat bed trailer attached to a truck. After refueling and taking on more chemicals, the pilot reported that when he lifted off the trailer, the helicopter's engine lost power, causing the helicopter to settle downward, resulting in the main rotor blades striking the cab of the truck. Examination of the helicopter revealed the engine to transmission drive shaft flex coupling had failed. Corrosion was found on both flex coupling components. ## Factual narrative On March 16, 1999, about 1001 central standard time, a Fairchild Hiller FH-1100 helicopter, N547FH, operated by Ward Aviation Inc., lost power during liftoff and collided with the cab of a truck near Opp, Alabama. Visual meteorological conditions prevailed at the time, and no flight plan was filed for the 14 CFR Part 137 aerial application flight. The helicopter was substantially damaged. The commercial-rated pilot reported no injuries. The flight was originating at the time. The helicopter had completed a 2-hour aerial application flight and returned to the helipad to refuel and reload. The helipad was a flatbed trailer attached to a truck. After refueling and taking on more chemicals, the pilot reported that when he lifted off the trailer, the helicopter's engine lost power, causing the helicopter to settle downward, resulting in the main rotor blades striking the cab of the truck. According to the FAA inspector's statement, "...inspection of the helicopter...revealed failure of the engine to transmission drive shaft flex coupling...physical breakup of the flex coupling with metal particles present. Both flex coupling components were covered with rust. Failure prior to ground impact was evident due to the extensive surface abrasions caused by the failure of the coupling and countinued operation of the engine." ## Aircraft - Registration: [N547FH](https://openairdocs.org/deregistered/N547FH-2018-02-15), registration cancelled 2018-02-15, S/N 47, built 1967 (OpenAirDocs) - Reported make and model: Fairchild Hiller FH-1100 - Registry model: [Fairchild Hiller FH-1100](https://openairdocs.org/model/fairchild-hiller-fh-1100) (registry code 3376502) (OpenAirDocs) - Registry engine: [Allison 250 SER 250HP](https://openairdocs.org/engine/allison-250-ser-250hp) (registry code 03002, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: 47 - Engines: Allison C-18-250 317 horsepower turbo shaft - Damage: Substantial damage - Flight: Aerial application, Part 137 - Registered owner: Darrel Ward - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, March 15, 1999, 10 hours before ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 54; flight instructor, commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: right; flight hours: 26,000 total, 2,100 in this make and model, 25,000 as pilot in command, 50 in the last 90 days, 40 in the last 30 days, 10 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 0° at 4 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 55 °F, dew point 36 °F - Altimeter: 30.00 inHg - Observed at: OZR, 15 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 19990316002459A](https://openairdocs.org/incident/19990316002459A), Mar 16, 1999: Hiller FH1100, Opp, AL, Substantial damage. 1967 Fairchild Hiller FH1100 helicopter lifted off, lost power, and the main rotor struck the cab of a pickup truck, other circumstances are unknown. (-23)… 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.