Sunday, January 26, 2020

Fire (Non-Impact): Wittman Tailwind, N625JS; fatal accident occurred April 15, 2018 in San Antonio, Texas

Main Wreckage at Accident Site.
National Transportation Safety Board

Fuselage and Empennage.
National Transportation Safety Board

National Transportation Safety Board

Propeller Hub.
National Transportation Safety Board

The National Transportation Safety Board traveled to the scene of this accident.

Additional Participating Entities:

Federal Aviation Administration / Flight Standards District Office; San Antonio, Texas
Lycoming Engines; Arlington, Texas

Aviation Accident Final Report - National Transportation Safety Board:

Investigation Docket - National Transportation Safety Board:

Location: San Antonio, TX
Accident Number: CEN18FA139
Date & Time: 04/15/2018, 1030 CDT
Registration: N625JS
Aircraft: WITTMAN W10
Aircraft Damage: Destroyed
Defining Event: Fire/smoke (non-impact)
Injuries: 1 Fatal
Flight Conducted Under: Part 91: General Aviation - Personal 


The commercial pilot was conducting a personal flight in his amateur-built airplane to accumulate additional flight time on the overhauled engine. A witness reported that he initially saw the airplane flying about 1,500 ft above the ground with no noticeable engine issues; however, as the airplane flew past his position, the engine began "struggling" for about 10 seconds before power was lost. The witness stated that the airplane was on fire as it descended into terrain. Another witness reported seeing fire coming from the bottom of the airplane while it was inflight. He also stated that the airplane briefly pitched up before it suddenly banked and descended nose down into terrain. The airplane was destroyed by impact forces and fire. A functional test of the engine and a comprehensive examination of the airplane's fuel system were not possible due to impact and fire damage. A partial teardown examination showed no evidence of a mechanical malfunction that would have precluded normal operation during the flight. 

Probable Cause and Findings

The National Transportation Safety Board determines the probable cause(s) of this accident to be:
An in-flight fire and subsequent total loss of engine power for reasons that could not be determined due to extensive impact and fire damage, followed by a loss of airplane control. 


Performance/control parameters - Not attained/maintained (Cause)

Not determined
Not determined - Unknown/Not determined (Cause)

Factual Information

History of Flight

Fuel related
Fire/smoke (non-impact) (Defining event)
Loss of engine power (total)

Loss of control in flight
Uncontrolled descent

Collision with terr/obj (non-CFIT)
Explosion (post-impact)

On April 15, 2018, about 1030 central daylight time, an amateur-built Wittman Tailwind W-10 airplane, N625JS, impacted terrain near San Antonio, Texas. The commercial pilot was fatally injured, and the airplane was destroyed by impact forces and fire. The airplane was registered to and operated by the pilot as a Title 14 Code of Federal Regulations Part 91 personal flight. Visual meteorological conditions prevailed for the flight, which departed Castroville Municipal Airport (CVB), Castroville, Texas, about 1025 and was destined for Freedom Springs Ranch Airport (TA66), Pipe Creek, Texas.

A friend of the pilot reported that the purpose of the flight was to accumulate additional flight time with the overhauled engine that had been installed on the airplane during its last condition inspection about 6.5 months before the accident. The pilot's friend reported the pilot had planned to fly from TA66 to CVB to purchase fuel. The pilot's friend also reported that the airplane departed TA66 about 0900. Fueling records showed that the pilot purchased 6.87 gallons of 100 low-lead aviation fuel about 1018 from a self-service fuel pump located at CVB. There were no witnesses to the airplane landing, refueling, or departing CVB.

A witness located about 1 mile from the accident site reported that he initially saw the airplane flying about 1,500 ft above the ground with no noticeable engine issues but that, as the airplane flew past his position, the engine was "struggling" for about 10 seconds, and a total loss of power followed. The witness stated that the airplane was on fire as it descended nose down into terrain. The witness did not observe any black smoke but observed a "fireball" as the airplane descended.

Another witness located near the accident site reported that the airplane was flying west at a very low altitude with fire coming from the bottom of the airplane. The witness stated that, after the airplane passed over, it briefly pitched up before it suddenly banked and descended nose down into the ground west of his position. The witness reported that the airplane "exploded into a fireball" when the airplane impacted the ground.

A review of available Federal Aviation Administration (FAA) air traffic control radar data revealed no transponder data associated with the flight.

Carl Edward Bray 
 Carl died doing what he loved to do, flying. He served in the United States Marine Corps and was a Vietnam Veteran. Carl was an excellent pilot, and in retirement spent most of his days working on his plane and flying.

Pilot Information

Certificate: Flight Instructor; Commercial
Age: 68, Male
Airplane Rating(s): Multi-engine Land; Single-engine Land
Seat Occupied: Left
Other Aircraft Rating(s): None
Restraint Used:
Instrument Rating(s): Airplane
Second Pilot Present: No
Instructor Rating(s): Airplane Single-engine
Toxicology Performed: Yes
Medical Certification: BasicMed
Last FAA Medical Exam: 02/02/2016
Occupational Pilot: No
Last Flight Review or Equivalent: 01/25/2018
Flight Time: (Estimated) 1149 hours (Total, all aircraft) 

According to FAA records, the 68-year-old pilot held a commercial pilot certificate with airplane single-engine land, airplane multiengine land, and instrument airplane ratings. The pilot also held an expired flight instructor certificate for single-engine airplanes. His most recent FAA third-class medical certificate was issued on February 2, 2016, with a limitation that required him to possess glasses for near vision and that he must use hearing amplification. On his medical certificate application, the pilot reported 1,149 hours of total flight experience, 35 hours of which occurred within the previous 6 months. The pilot's third-class medical certificate expired on February 28, 2018, but he had completed the BasicMed medical education course and received a comprehensive medical examination from his physician on March 8, 2018.

A review of the pilot's logbook revealed that he stopped recording individual flights after December 31, 2006. As of that date, the pilot had accumulated 845.1 hours of flight experience, of which 828.1 hours and 17 hours were logged in single-engine and multiengine airplanes, respectively. At that time, he had accumulated 296.1 hours in the accident airplane make and model. The remainder of the flight log included multiple flight reviews and two entries for combined flight time in Cessna 172 airplanes (One entry totaling 175.2 hours for flights flown between September 12, 2012, and January 25, 2016, and another entry totaling 43.8 hours for flights flown between January 16, 2016, and April 1, 2017). The final logbook entry, dated January 25, 2018, was for a flight review in a Cessna 172. The pilot's flight history between the final logbook entry and the date of the accident could not be determined nor could his recency of experience in the accident airplane.

Aircraft and Owner/Operator Information

Aircraft Make: WITTMAN
Registration: N625JS
Model/Series: W10
Aircraft Category: Airplane
Year of Manufacture: 1986
Amateur Built:Yes 
Airworthiness Certificate: Experimental
Serial Number: JS466
Landing Gear Type: Tailwheel
Seats: 2
Date/Type of Last Inspection: 09/30/2017, Condition
Certified Max Gross Wt.:
Time Since Last Inspection:
Engines: 1 Reciprocating
Airframe Total Time: 984.9 Hours as of last inspection
Engine Manufacturer: Lycoming
ELT: Installed
Engine Model/Series: O-290-D
Registered Owner: On file
Rated Power: 125 hp
Operator: On file
Operating Certificate(s) Held: None

The amateur-built airplane, serial number JS466, was constructed with a steel tube fuselage, wood wings, and fabric covering. The two-seat, high-wing monoplane was equipped with fixed conventional landing gear and flaps. The airplane was powered by a 125-horsepower, 4-cylinder, Lycoming O-290-D reciprocating engine, serial number 1355-20-16. The engine provided thrust through a fixed-pitch, two-blade Aymar-DeMuth 70X62 wood propeller. On November 7, 1986, the airplane received its original special airworthiness certificate from the FAA. On April 11, 1993, the builder applied for an updated special airworthiness certificate and associated operating limitations. The pilot purchased the airplane on January 10, 2004, and its registration certificate was issued on February 26, 2004.

The airplane's recording tachometer was destroyed during the postimpact fire, which precluded a determination of the airplane's total time. According to maintenance documentation, the last condition inspection was completed on September 30, 2017, when the airframe had accumulated a total of 984.9 hours. A field-overhauled engine was installed on the airplane during the last condition inspection. The final logbook entry was for an engine oil change completed on December 10, 2017, when the airframe had accumulated a total of 997.4 hours. At that time, the engine had accumulated 12.5 hours since its overhaul. A postaccident review of the maintenance records found no evidence of unresolved airworthiness issues.

The airplane was equipped with a header fuel tank that supplied fuel directly to the engine carburetor. On April 15, 2011, the fuel tank was removed to repair a leak at the upper aft left corner of the tank. At that time, the airframe had accumulated a total of 965 hours.

Meteorological Information and Flight Plan

Conditions at Accident Site: Visual Conditions
Condition of Light: Day
Observation Facility, Elevation: CVB, 774 ft msl
Distance from Accident Site: 5 Nautical Miles
Observation Time: 1035 CDT
Direction from Accident Site: 204°
Lowest Cloud Condition: Clear
Visibility:  10 Miles
Lowest Ceiling: None
Visibility (RVR):
Wind Speed/Gusts: Calm /
Turbulence Type Forecast/Actual: None / None
Wind Direction:
Turbulence Severity Forecast/Actual: N/A / N/A
Altimeter Setting: 30.26 inches Hg
Temperature/Dew Point: 19°C / -2°C
Precipitation and Obscuration: No Obscuration; No Precipitation
Departure Point: Castroville, TX (CVB)
Type of Flight Plan Filed: None
Destination: Pipe Creek, TX (TA66)
Type of Clearance: None
Departure Time: 1025 CDT
Type of Airspace: Class G

A postaccident review of available meteorological data established that day visual meteorological conditions prevailed at the accident site. The nearest aviation weather reporting station was located at CVB about 5 miles south-southwest of the accident site. At 1035, about 5 minutes after the accident, the CVB automated surface observing system reported a clear sky, calm wind, 10 miles surface visibility, temperature 19°C, dew point -2°C, and an altimeter setting of 30.26 inches of mercury.

Wreckage and Impact Information

Crew Injuries: 1 Fatal
Aircraft Damage: Destroyed
Passenger Injuries: N/A
Aircraft Fire: In-Flight and On-Ground
Ground Injuries: N/A
Aircraft Explosion: On-Ground
Total Injuries: 1 Fatal
Latitude, Longitude: 29.413333, -98.815000 

The airplane collided with terrain vegetated with tall mesquite bush, yucca, and persimmon trees. The airplane impacted terrain in a 20° nose-down pitch attitude on a 281° magnetic heading. The initial impact point was with a 15-ft tall tree. Fragmented pieces of the left wing and broken branches were found at the base of the tree. The debris located at the base of the tree showed no fire damage. A debris path extended about 50 ft from the initial impact point to the main wreckage. Fuel blight was observed on the tree leaves located along and adjacent to the debris path. Fragmented pieces of the left wing, including the wing spar, left aileron, and left flap, were located about 12 ft from the initial impact point on the left side of the debris path. The left aileron remained attached to the trailing edge of the wing. The left flap remained partially attached to the wing and exhibited bending in multiple locations.

The ground impact area measured about 3.5 ft at its widest point and 8 ft at its longest point . Dirt and vegetation had been ejected from the ground impact area in the direction of the main wreckage. Charred material consistent with the cowling and engine baffles were located at the west end of the ground scar. The debris path consisted of engine components, torn, burned, and fragmented wood and metal components, a seat frame, the left door frame, and the burned remains of the right main landing gear tire. The burnt and fragmented remains of the right wing, including the right aileron and right flap, came to rest on the left side of the debris field. There was burnt vegetation preceding the main wreckage and evidence of an extensive ground fire that extended about 200 ft north of the main wreckage.

The main wreckage, which came to rest inverted, included the burnt and charred remains of the fuselage frame and empennage, main landing gear assembly, engine, and propeller. Most of the fuselage, including the cockpit and instrument panel, was destroyed by fire, so no reliable readings could be obtained from any of the instruments, gauges, or radios. Flight control continuity for the aileron and elevator controls could not be established due to extensive fire and impact damage. Control cable continuity was confirmed from the rudder control horns forward to the rudder pedals. The flap selection lever was in the flaps fully retracted position. The entire fuel system, including the header fuel tank, was destroyed by fire.

Mechanical continuity from the engine components to their respective cockpit controls could not be established due to impact and fire damage. The engine had separated from the airframe and came to rest adjacent to the main wreckage. A functional test of the engine was not possible due to extensive impact and fire damage. The wood propeller blades were fragmented during the impact and were fire damaged. The carburetor had separated from the engine and was located within the debris field. The internal carburetor float had melted, consistent with prolonged exposure to fire. The upper spark plugs exhibited features consistent with normal engine operation. Both magnetos had separated from the engine, and the impact and fire damage precluded functional testing. Rotation of the crankshaft and camshaft was not possible due to extensive fire and impact damage. A partial disassembly of the engine did not reveal any preimpact anomalies with the crankshaft, cylinders, valves, valve seats, pistons, and connecting rods. Although the engine exhibited significant impact and fire damage, there was no evidence of a mechanical malfunction that would have precluded normal operation during the flight. 

Medical And Pathological Information

The Bexar County Medical Examiner's Office, San Antonio, Texas, performed an autopsy of the pilot. His cause of death was attributed to multiple blunt force injuries. The autopsy found no evidence of soot inhalation. Toxicology testing performed at the FAA Forensic Sciences Laboratory was negative for ethanol and all tested drugs and medications.

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