# NTSB ANC93LA154: Helio H-295, N42DC, Mt. Deborah, AK, August 15, 1993 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: August 15, 1993, 12:30 local (20:30 UTC) - Place: Mt. Deborah, AK - Coordinates: 63.700325, -144.890045 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=63.7003&lon=-144.8900&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report September 26, 1994 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - NTSB case key (mKey): 2410 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC93LA154 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/2410/pdf - Page: https://openairdocs.org/ntsb/ANC93LA154 ## Probable cause FAILURE OF THE RIGHT MAIN LANDING GEAR LEG DUE TO THE IMPROPER MAJOR REPAIR PERFORMED ON THE GEAR LEG BY SOME UNKNOWN MAINTENANCE PERSON(S). ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Main gear collapsed, landing - roll - landing gear,main gear - failure,total (cause) - maintenance,major repair - improper, other maintenance personnel (cause) ## Analysis DURING THE LANDING ROLL AT A REMOTE SITE THE RIGHT MAIN LANDING GEAR COLLAPSED AND THE RIGHT WING DRAGGED THE GROUND. EXAMINATION REVEALED THAT THE RIGHT MAIN LANDING GEAR LEG, PART NUMBER 250 040 451 1, FAILED AT THE UPPER WELD. FURTHER EXAMINATION REVEALED AN UNDOCUMENTED PREVIOUS REPAIR AT THE FAILED AREA. IT WAS FOUND THAT THE GEAR LEG METAL HAD BEEN IMPROPERLY HEAT TREATED FOLLOWING THAT REPAIR. ## Factual narrative On August 15, 1993, at 1230 Alaska daylight time, a wheel equipped Helio H 295 airplane, N42DC, operated by Wright Air Service, Inc., of Fairbanks, Alaska, experienced a collapsed main landing gear and dragged a wing while landing at a remote hunting strip near Mount Deborah, Alaska, and about 40 miles southwest of Delta Junction, Alaska. The airline transport pilot, the sole occupant, was not injured, and the airplane was substantially damaged. The positioning flight, operating under 14 CFR Part 91, departed another nearby remote strip at about 1200. Visual meteorological conditions existed, and a company VFR flight plan was filed. The pilot stated that during the landing roll the right main landing gear collapsed, and the right wing hit the ground. ## Aircraft - Registration: [N42DC](https://openairdocs.org/deregistered/N42DC-2001-08-15), registration cancelled 2001-08-15, S/N 1454 (OpenAirDocs) - Reported make and model: HELIO H-295 - Registry model: [Helio H-295](https://openairdocs.org/model/helio-h-295) (registry code 4300802) (OpenAirDocs) - Category: Airplane - Serial number: 1454 - Airframe hours: 2726 - Engines: LYCOMING GO-480-G1D6 295 horsepower reciprocating - Damage: Substantial damage - Flight: Positioning, Part 91 - Operator: Bursiel, Robert P., doing business as Wright Air Service, Inc. - Registered owner: Bursiel, Robert P. - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, July 2, 1993, 93 hours before - Flight plan: Company VFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 44; commercial, flight engineer; airplane ratings: multi-engine land, single-engine sea, multi-engine sea, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: left; toxicology performed; flight hours: 15,300 total, 5,000 in this make and model, 15,000 as pilot in command, 200 in the last 90 days, 75 in the last 30 days, 4 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: variable at 13 knots - Visibility: 20 statute miles - Lowest ceiling: none - Temperature: 45 °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 19930815032749A](https://openairdocs.org/incident/19930815032749A), Aug 15, 1993: Helio H295, Mt Deborah, AK, Substantial damage. Right main landing gear collapsed on landing at remote strip. Upper weld failed. Prior repair improperly heated. ## Other investigations on N42DC (2) 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 ANC01LA039](https://openairdocs.org/ntsb/ANC01LA039), Mar 3, 2001: Helio H-295 (N42DC), Clear, AK, substantial damage. Probable cause: The shifting of engine connecting rod bearings, and the fracture of an engine connecting rod. - [NTSB ANC94LA046](https://openairdocs.org/ntsb/ANC94LA046), Apr 8, 1994: Helio 295 (N42DC), Manley Hot Sprg, AK, substantial damage. Probable cause: FUEL STARVATION CAUSED BY A BLOCKED FUEL VENT LINE. A FACTOR IN THE ACCIDENT WAS THE IMPROPER AIRCRAFT PREFLIGHT. 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.