The National Transportation Safety Board did not travel to the scene of this accident.
Additional Participating Entities:
Federal Aviation Administration / Flight Standards District Office; Lubbock, Texas
Continental Motors; Mobile, Alabama
Aviation Accident Final Report - National Transportation Safety Board: https://app.ntsb.gov/pdf
Investigation Docket - National Transportation Safety Board: https://dms.ntsb.gov/pubdms
http://registry.faa.gov/N3600A
Accident Number: CEN18LA084
Date & Time: 01/22/2018, 0845 CST
Registration: N3600A
Aircraft: BEECH A36
Aircraft Damage: Substantial
Defining Event: Powerplant sys/comp malf/fail
Injuries: 1 Serious
Flight Conducted Under: Part 91: General Aviation - Personal
Analysis
The private pilot was conducting a cross-country, personal flight. He stated that, upon leveling off at cruise altitude, there was a "severe vibration" coming from the engine compartment, followed by a sound of the engine "coming apart." Oil covered the windshield, and the smoke entered the cockpit. The pilot was unable to return to the departure airport because it was beyond gliding distance, so he performed a forced landing on a field with the landing gear and flaps retracted. The pilot sustained serious injuries.
Postaccident examination of the engine revealed a large hole in the left crankcase half over the No. 2 cylinder attachment point and a small hole in the right crankcase half over the No. 5 cylinder attachment point. The No. 2 main bearing had shifted in the bearing saddle, which cut off the oil supply to the No. 2 rod cap bearing. Shifting/slipping of the bearing can result from either improper torque application during cylinder replacement or improper grinding of the bearing journal during maintenance.
The engine had been disassembled twice before the accident. An engine logbook entry showed that the No. 2 cylinder had been removed and replaced about 328 hours before the accident. It is likely that maintenance personnel did not conduct proper maintenance on the No. 2 cylinder during reassembly of the engine and that this ultimately led to the catastrophic engine failure due the shifting/slipping of the No. 2 bearing and the subsequent oil starvation and total loss of engine power.
Probable Cause and Findings
The National Transportation Safety Board determines the probable cause(s) of this accident to be:
Maintenance personnel improper maintenance of the engine, which resulted in a catastrophic engine failure due the shifting/slipping of the No. 2 bearing and the subsequent oil starvation and total loss of engine power during cruise flight.
Findings
Aircraft
Engine (reciprocating) - Failure (Cause)
Oil - Not specified (Cause)
Scheduled maint checks - Incorrect service/maintenance (Cause)
Personnel issues
Repair - Maintenance personnel (Cause)
Factual Information
On January 22, 2018, at 0845 central standard time, a Beech A36, N3600A experienced a total loss of engine power during climb after departing from Abilene Regional Airport (ABI), Abilene, Texas. The private pilot then performed a forced landing to a field near Abilene, Texas. The pilot sustained serious injuries and the airplane sustained minor damage. The airplane was registered to and operated by the pilot under Title 14 Code of Federal Regulations Part 91 as a personal flight that was operating on a visual flight rules flight plan. Day visual meteorological conditions prevailed at the time of the accident. The flight originated from ABI at 0835 and was destined to Sierra Blanca Regional Airport (SRR), Ruidoso, New Mexico.
The pilot stated that upon level off at cruise altitude, there was a "severe vibration" from the engine compartment followed by a sound of the engine "coming apart." Oil covered the windshield and the smoke entered the cockpit. The pilot stated that he was unable to return to ABI due to its distance from his position and attempted a forced landing to Dyess Air Force Base (AFB), Texas. The pilot was unable to attain Dyess AFB due to the airplane's altitude. The pilot performed a forced landing to a field about one mile southwest of Dyess AFB with the landing gear and flaps retracted.
Post-accident examination revealed the engine was intact with all the accessories attached. A large hole was observed in the left crankcase half over the number two-cylinder attachment point, and a small hole was observed in the right crankcase half over the number five-cylinder attachment point. Cylinders two, four, and six were Continental cylinders and had chrome markings. Cylinders one, three, and five were ECI cylinders.
The number 2 main bearing shifted in the bearing saddle, which cut off the oil supply to the number 2 rod cap bearing. The number 2 connecting rod separated from the connecting rod journal on the crankshaft. The number 2 rod journal on the crankshaft was very dry and partly melted. The number 2 rod cap bearing was melted and most of it was found in the oil sump.
The engine logbook had an entry dated January 23, 2015, at a tachometer time of 4,173 hours, for the removal and replacement of the number two cylinder.
The most recent entry for disassembly of the engine, as part of an annual inspection, was dated February 12, 2016, at a tachometer time of 4,299.6 hours and 1,796.0 hours since overhaul. The entry states, "#4 and #6 cylinders were removed due to exhaust leaks." The mechanic who performed the annual inspection dated February 12, 2016 performed the most recent annual dated February 9, 2017, at a tachometer time of 4,442.7 hours.
The tachometer indication at the time of the accident was 4,501.0 hours.
History of Flight
Prior to flight
Aircraft maintenance event
Enroute-climb to cruise
Powerplant sys/comp malf/fail (Defining event)
Loss of engine power (total)
Landing
Off-field or emergency landing
Miscellaneous/other
Pilot Information
Certificate: Private
Age: 71, Male
Airplane Rating(s): Single-engine Land
Seat Occupied: Left
Other Aircraft Rating(s): None
Restraint Used: 3-point
Instrument Rating(s): None
Second Pilot Present: No
Instructor Rating(s): None
Toxicology Performed: No
Medical Certification: Class 3 With Waivers/Limitations
Last FAA Medical Exam: 09/22/2016
Occupational Pilot: No
Last Flight Review or Equivalent: 11/02/2016
Flight Time: 702 hours (Total, all aircraft), 350 hours (Total, this make and model), 702 hours (Pilot In Command, all aircraft), 7 hours (Last 90 days, all aircraft), 2 hours (Last 30 days, all aircraft)
Aircraft and Owner/Operator Information
Aircraft Make: BEECH
Registration: N3600A
Model/Series: A36
Aircraft Category: Airplane
Year of Manufacture: 1978
Amateur Built: No
Airworthiness Certificate: Utility
Serial Number: E-1328
Landing Gear Type: Retractable - Tricycle
Seats: 6
Date/Type of Last Inspection: 02/09/2017, Annual
Certified Max Gross Wt.: 3600 lbs
Time Since Last Inspection: 58 Hours
Engines: 1 Reciprocating
Airframe Total Time: 4501 Hours at time of accident
Engine Manufacturer: Continental
ELT: Installed, activated, did not aid in locating accident
Engine Model/Series: IO-520-BA
Registered Owner: Pilot
Rated Power: 285 hp
Operator: Pilot
Operating Certificate(s) Held: None
Meteorological Information and Flight Plan
Conditions at Accident Site: Visual Conditions
Condition of Light: Day
Observation Facility, Elevation: DYS, 1790 ft msl
Distance from Accident Site: 2 Nautical Miles
Observation Time: CST
Direction from Accident Site: 225°
Lowest Cloud Condition: Clear
Visibility: 10 Miles
Lowest Ceiling: None
Visibility (RVR):
Wind Speed/Gusts: 12 knots /
Turbulence Type Forecast/Actual: / None
Wind Direction: 280°
Turbulence Severity Forecast/Actual: / N/A
Altimeter Setting: 30.12 inches Hg
Temperature/Dew Point: 5°C / -8°C
Precipitation and Obscuration: No Obscuration; No Precipitation
Departure Point: Abilene, TX (ABI)
Type of Flight Plan Filed: VFR
Destination: Abilene, TX (DYS)
Type of Clearance: VFR
Departure Time: 0835 CST
Type of Airspace: Class C
Airport Information
Airport: Dyess Air Force Base (DYS)
Runway Surface Type: Grass/turf
Airport Elevation: 1790 ft
Runway Surface Condition: Vegetation
Runway Used: N/A
IFR Approach: None
Runway Length/Width:
VFR Approach/Landing: Forced Landing
Wreckage and Impact Information
Crew Injuries: 1 Serious
Aircraft Damage: Substantial
Passenger Injuries: N/A
Aircraft Fire: None
Ground Injuries: N/A
Aircraft Explosion: None
Total Injuries: 1 Serious
Latitude, Longitude: 32.448611, -99.733056 (est)
How can the pilot have "serious" injuries when the aircraft only has "minor" damage from a gear up soft field landing? It's sitting there perfect minus gear and even the wing tips appear to be undamaged. It hit nothing. Makes no sense to me.
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