# NTSB ANC90FA134: Helio Courier H-295, N6493V, 40 Se Bettles, AK, August 4, 1990 - Type: NTSB accident investigation - Classification: Accident · Fatal · Field investigation · Final report - Date: August 4, 1990, 15:05 local (23:05 UTC) - Place: 40 Se Bettles, AK - Coordinates: 67.240203, -152.270156 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=67.2402&lon=-152.2702&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: Fatal - Injuries: 3 fatal - Status: Completed, report April 30, 1992 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - NTSB case key (mKey): 5303 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC90FA134 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/5303/pdf - Page: https://openairdocs.org/ntsb/ANC90FA134 ## Probable cause THE FAILURE AND SEPARATION OF THE #5 CONNECTING ROD BOLT AND CAP WHICH RESULTED IN THE RUPTURE OF THE ENGINE HOUSING AND SUBSEQUENT ENGINE FIRE DUE TO OIL SPILLAGE, AND AN INADEQUATELY MOUNTED VERTICAL FIN/STABILATOR. A CONTRIBUTING FACTOR WAS THE INADEQUATE MAINTENANCE AND INSPECTION OF THE AIRCRAFT AFTER A PREVIOUS ACCIDENT. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(total) - mech failure/malf, cruise - normal - engine assembly - previous damage (contributing factor) - maintenance,inspection - inadequate, other maintenance personnel (contributing factor) - engine assembly,connecting rod bolt - separation (cause) - engine assembly,connecting rod cap - separation (cause) - engine assembly,crankcase - fractured (cause) - Fire, cruise - normal - engine assembly - fire (contributing factor) - Loss of control - in flight, descent - emergency - stabilizer - loose (cause) - maintenance,inspection - inadequate, other maintenance personnel (contributing factor) - Airframe/component/system failure/malfunction, descent - emergency - wing - overload - In flight collision with terrain/water, descent - uncontrolled ## Analysis THE PILOT HAD INDICATED TO BETTLES FSS THAT HE HAD LOST POWER AND THAT HE HAD A FIRE ON BOARD. THE WRECKAGE WAS SUBSEQUENTLY LOCATED 40 MILES SE OF BETTLES. ON-SITE EXAMINATION SHOWES THAT THE RIGHT WING, BOTH AILERONS, LEFT FLAP, RUDDER, VERTICAL FIN AND STABILATOR HAD ALL SEPARATED FROM THE AIRPLANE IN FLIGHT. TWO OF THE THREE VERTICAL FIN/STABILATOR-TO-FUSELAGE MOUNTS HAD FAILED IN OVERLOAD; THE THIRD MOUNT WAS RELATIVELY UNDAMAGED WITH THE BOLT MISSING AND VISIBLE ELONGATION OF THE BOLT HOLE. ENGINE EXAM REVEALED EXTENSIVE FIRE DAMAGE TO THE #5 CYLINDER, THE HEAD AREA HAVING BEEN COMPLETELY CONSUMED BY FIRE. THE ROD CAP AND ONE BOLT COULD NOT BE FOUND AT THE WRECKAGE SITE. FOUR MONTHS PRIOR TO THE ACCIDENT MAJOR REPAIRS WERE MADE TO THE AIRFRAME, THE ENGINE NOSE CASE WAS REMOVED AND OVERHAULED, AND THE PROPELLER WAS OVERHAULED. AIRCRAFT AND PILOT INVOLVED IN LANDING ACCIDENT ON 6/29/88 SUBSTANTIALLY DAMAGING THE AIRCRAFT. LYCOMING SB RECOMMENDS ENGINE TEARDOWN AFTER SUDDEN STOPPAGE; NO RECORD OF COMPLIANCE. ## Aircraft - Registration: [N6493V](https://openairdocs.org/deregistered/N6493V-1991-08-15), registration cancelled 1991-08-15, S/N 1458 (OpenAirDocs) - Reported make and model: HELIO COURIER H-295 (COURIER H-) - Registry model: [Helio H-295](https://openairdocs.org/model/helio-h-295) (registry code 4300802) (OpenAirDocs) - Category: Airplane - Serial number: 1458 - Airframe hours: 3986 - Engines: LYCOMING GO-480-G1D6 295 horsepower reciprocating - Damage: Destroyed - Fire: In-Flight - Flight: Business, Part 91 - Operator: Metheny, James R - Registered owner: Vixie Rochester - Airworthiness certificate: Standard, Normal - Last inspection: Annual, April 1, 1990 - Departed: Z84, CLEAR, AK - Destination: HAPPY VALLEY, AK - Flight plan: VFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 61; commercial; airplane ratings: single-engine land, single-engine sea, multi-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; toxicology performed; flight hours: 7,765 total ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 30 statute miles - Lowest ceiling: none - Temperature: 61 °F, dew point 41 °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 19900804030069A](https://openairdocs.org/incident/19900804030069A), Aug 4, 1990: Helio H295, Bettles, AK, Destroyed, 3 fatal. Connecting rod bolts failed. Rod broke through case. Hot oil on turbo caused fire. Lost control. Broke up in flight ## Other investigations on N6493V (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 ANC88LA077](https://openairdocs.org/ntsb/ANC88LA077), Jun 29, 1988: Helio H-295 (N6493V), Clear, AK, substantial damage - [NTSB ANC76FAA31](https://openairdocs.org/ntsb/ANC76FAA31), Apr 9, 1976: Helio Acft H-295 (N6493V), 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.