# NTSB SEA95LA220: Hiller UH-12A, N8180H, Bonners Ferry, ID, September 17, 1995 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: September 16, 1995, 18:30 local (Sep 17, 1995, 01:30 UTC) - Place: Bonners Ferry, ID - Coordinates: 48.749912, -116.509597 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=48.7499&lon=-116.5096&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report February 27, 1996 - Report: Approved by Office Director - NTSB case key (mKey): 42251 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA95LA220 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/42251/pdf - Page: https://openairdocs.org/ntsb/SEA95LA220 ## Probable cause THE FLIGHT INSTRUCTOR'S MISJUDGING HIS FLARE DURING A SIMULATED AUTOROTATION. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Hard landing, landing - flare/touchdown - flare - misjudged, pilot in command(cfi) (cause) - autorotation - simulated, pilot in command(cfi) ## Analysis DURING A DEMONSTRATION AUTO-ROTATION LANDING, THE FLIGHT INSTRUCTOR MISJUDGED HIS ELEVATION ABOVE THE GROUND IN THE FLARE AND LANDED HARD, SEVERING THE ROTORCRAFT'S TAILBOOM. ## Factual narrative On September 16, 1995, approximately 1830 hours Pacific daylight time, a Hiller UH-12A, N8180H, being flown by a commercial flight instructor, was substantially damaged during a hard landing following an auto-rotation approximately six miles north northwest of Bonners Ferry, Idaho. Visual meteorological conditions prevailed and no flight plan had been filed. The flight, which was instructional, was to have been operated under 14CFR91, and originated from the Boundary County Airport, Bonners Ferry, Idaho. The instructor pilot reported that he was demonstrating a practice auto-rotation to the owner/student pilot when the aircraft impacted the ground and the left skid collapsed. He reported that during the maneuver he "began to raise collective pitch to cushion the landing, (and) it was at this point in the autorotation that I made contact with the ground. I misjudged my elevation by approximately 5 to 10 feet." The main rotor blade severed the tail boom during the ground impact. The instructor pilot reported that there was no mechanical malfunction with the aircraft at the time of the accident. ## Aircraft - Registration: [N8180H](https://openairdocs.org/aircraft/N8180H), registered now, S/N 180, built 1950 (OpenAirDocs) - Reported make and model: HILLER UH-12A - Registry model: [Hiller UH-12A](https://openairdocs.org/model/hiller-uh-12a) (registry code 4360104) (OpenAirDocs) - Registry engine: [Franklin 6VS-335 series](https://openairdocs.org/engine/franklin-6vs-335-series) (registry code 27040, reciprocating) (OpenAirDocs) - Category: Helicopter - Serial number: 180 - Engines: FRANKLIN 6V350B 235 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Operator: Davis, Robert, L. - Registered owner: Wilderness Helicopters, Ltd. - Airworthiness certificate: Standard, Normal - Last inspection: Annual, August 21, 1995, 26 hours before - Departed: 65S, ID ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 41; commercial; airplane ratings: single-engine land; medical: class 2, valid medical--no waivers/lim.; seat: left; flight hours: 1,774 total, 1,107 in this make and model, 1,659 as pilot in command, 296 in the last 90 days, 42 in the last 30 days, 7 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 50 statute miles - Lowest ceiling: none - Temperature: 84 °F ## 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 19950916029899A](https://openairdocs.org/incident/19950916029899A), Sep 16, 1995: Hiller UH12A, Bonners Ferry, ID, Substantial damage. Hard autorotation landing. Skid collapsed. Rotors chopped tailboom CFI misjudged flare height. Late on collective. ## Other investigations on N8180H (3) 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. - [NTSB ATL07LA045](https://openairdocs.org/ntsb/ATL07LA045), Feb 24, 2007: Hiller UH-12A (N8180H), Bethlehem, GA, substantial damage, 2 fatal. Probable cause: The pilot's failure to maintain adequate rotor rpm, which resulted in an attempted autorotation and in-flight collision with trees. Contributing to the severity of the accident was the pilot… - [NTSB SEA71DWA05](https://openairdocs.org/ntsb/SEA71DWA05), Jul 11, 1970: Hiller Acft UH-12A (N8180H), Maupin, OR, substantial damage - [NTSB ANC67A0062](https://openairdocs.org/ntsb/ANC67A0062), Jun 14, 1967: Hiller UH-12A (N8180H), Fairbanks, AK, substantial damage 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.