Oil Pressure Switch with heat damage.
Continental Aerospace Technologies
Threaded end of oil pressure switch.
Continental Aerospace Technologies
The National Transportation Safety Board did not travel to the scene of this accident.
Additional Participating Entities:
Federal Aviation Administration / Flight Standards District Office; Irving, Texas
Continental Aerospace Technologies; Mobile, Alabama
Textron Aviation, Inc; Wichita, Kansas
Van Bortel Aircraft Inc; Arlington, Texas
Aviation Accident Factual Report - National Transportation Safety Board: https://app.ntsb.gov/pdf
Investigation Docket - National Transportation Safety Board: https://dms.ntsb.gov/pubdms
https://registry.faa.gov/N2514F
Accident Number:CEN19LA159
Date & Time: 05/30/2019, 1100 CDT
Registration: N2514F
Aircraft: Lancair LC41
Aircraft Damage: Substantial
Defining Event: Powerplant sys/comp malf/fail
Injuries: 1 None
Flight Conducted Under: Part 91: General Aviation - Business
On May 30, 2019, about 1100 central daylight time, a Lancair LC41 airplane, N2514F, conducted a forced landing near the Cleburne Regional Airport (CPT), Cleburne, Texas. The pilot was not injured, and the airplane sustained substantial damage. The airplane was registered to and operated by Van Bortel Aircraft, Inc under the provisions of Title 14 Code of Federal Regulations Part 91 as a maintenance test flight. Visual meteorological conditions prevailed for the local flight at the time of the accident.
The flight was conducted to break-in the engine's No. 5 cylinder, which had just been replaced. During the flight, the pilot noticed the oil pressure warning light illuminate, followed by a low oil temperature indication. The pilot attempted to divert to CPT; however, the engine experienced a loss of power and he conducted a forced landing. During the landing, the airplane collided with trees and came to rest upright and partly submerged in a small pond about one mile from CPT.
Inspection of the airplane revealed substantial damage to the wings, and water submersion damage to the airplane. The airplane's Hobbs meter read 1,090.1 hours.
The airplane was recovered to a secure facility for further examination. The examination was conducted by the NTSB Investigator-in-Charge, a representative from Van Bortel Aircraft, and technical representatives from the engine and airframe manufacturers. The examination noted the engine case had a hole above the No. 4 cylinder, and when the propeller was rotated by hand, the engine had limited rotation and internal binding was noted. A light, oil film was noted on the bottom of the airplane. The exam also found an oil pressure switch separated in two pieces. The threaded section remained to its mating joint; the other section rested on an exhaust tube and attached by its wire connector as seen in Figure 1.
Figure 1: Oil Pressure Switch
The switch was removed and sent to Textron Aviation, Inc, Materials Laboratory for a detailed examination of the switch. Textron's examination noted the switch failed at the swaged joint between the threaded section and the base cap section of the switch. The examination was not able to determine how the joint failed, since there were no physical indications as to how the swaged joint failed.
Pilot Information
Certificate: Airline Transport; Commercial; Flight Engineer
Age: 58
Airplane Rating(s): Multi-engine Land; Single-engine Land
Seat Occupied: Left
Other Aircraft Rating(s): None
Restraint Used: 3-point
Instrument Rating(s): Airplane
Second Pilot Present: No
Instructor Rating(s): Airplane Multi-engine; Airplane Single-engine
Toxicology Performed: No
Medical Certification: Class 1 Without Waivers/Limitations
Last FAA Medical Exam: 02/25/2019
Occupational Pilot:
Last Flight Review or Equivalent: 05/05/2019
Flight Time: 20019 hours (Total, all aircraft), 165 hours (Total, this make and model), 233 hours (Last 90 days, all aircraft), 73 hours (Last 30 days, all aircraft)
Aircraft and Owner/Operator Information
Aircraft Make: Lancair
Registration: N2514F
Model/Series: LC41 550FG
Aircraft Category: Airplane
Year of Manufacture:
Amateur Built: No
Airworthiness Certificate: Normal
Serial Number: 41093
Landing Gear Type: Tricycle
Seats:
Date/Type of Last Inspection: Annual
Certified Max Gross Wt.:
Time Since Last Inspection:
Engines: Reciprocating
Airframe Total Time: 1090.1 Hours at time of accident
Engine Manufacturer: Continental
ELT: C91A installed, activated, did not aid in locating accident
Engine Model/Series: TSIO-550-C(5)
Registered Owner: Van Bortel Aircraft, Inc
Rated Power: 310 hp
Operator: Van Bortel Aircraft, Inc
Operating Certificate(s) Held: None
Meteorological Information and Flight Plan
Conditions at Accident Site: Visual Conditions
Condition of Light: Day
Observation Facility, Elevation: KCPT
Distance from Accident Site:
Observation Time: 0955 CDT
Direction from Accident Site:
Lowest Cloud Condition: Clear
Visibility: 10 Miles
Lowest Ceiling:
Visibility (RVR):
Wind Speed/Gusts: 7 knots /
Turbulence Type Forecast/Actual:
Wind Direction: 350°
Turbulence Severity Forecast/Actual:
Altimeter Setting: 30.01 inches Hg
Temperature/Dew Point: 26°C / 17°C
Precipitation and Obscuration: No Precipitation
Departure Point: Arlington, TX (GKY)
Type of Flight Plan Filed: None
Destination: Arlington, TX (GKY)
Type of Clearance: None
Departure Time:
Type of Airspace:
Wreckage and Impact Information
Crew Injuries: 1 None
Aircraft Damage: Substantial
Passenger Injuries: N/A
Aircraft Fire: None
Ground Injuries: N/A
Aircraft Explosion: None
Total Injuries: 1 None
Latitude, Longitude: 32.390278, -97.433611 (est)
That metal base cap is joined to the base fitting by swaging of the metal stem sleeve of the threaded fitting where it protrudes inside the base cap. The swaging deforms the protruding sleeve such that it is larger than the hole in the base cap.
ReplyDeleteSeparation at that swaged connection means that there was force applied to the cap or body sufficient to overcome the enlarged sleeve and pull it through the hole in the cap.
If that melted spot in the plastic was there before the separation event, something hot was in contact and side-loading the body. Vibration adds to the forces. Seems odd that the report does not comment on what high temperature points of contact were adjacent while installed or in reach of it after coming apart and dangling from the wires.
Careful inspection for undesired points of contact might prevent this on your aircraft.